Recombinant proteins and their therapeutic uses
11198716 · 2021-12-14
Assignee
Inventors
Cpc classification
C07K14/4753
CHEMISTRY; METALLURGY
C07K14/485
CHEMISTRY; METALLURGY
A61P43/00
HUMAN NECESSITIES
C07K2319/40
CHEMISTRY; METALLURGY
C07K14/4748
CHEMISTRY; METALLURGY
C07K14/65
CHEMISTRY; METALLURGY
Y02P20/582
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
C12N9/12
CHEMISTRY; METALLURGY
A61P35/00
HUMAN NECESSITIES
International classification
A61K39/00
HUMAN NECESSITIES
C07K14/65
CHEMISTRY; METALLURGY
C12N9/12
CHEMISTRY; METALLURGY
C07K14/485
CHEMISTRY; METALLURGY
Abstract
A recombinant protein expressing one or more human growth factors, tumor antigens, and/or receptors or epitopes thereof on or within an immunogenic expression creating a recombinant protein in which one or more epitopes are presented on the surface of the sequence in their natural configuration. The growth factor, tumor antigen, and/or receptor, sequence(s) may be expressed within the encoding sequence at appropriate internal positions or at the termini as single expressions or as two or more tandem repeats.
Claims
1. A recombinant protein, comprising: an immunogenic polypeptide; a peptide spacer selected from the group consisting of SSGGG (SEQ. ID NO: 4), GGSGG (SEQ. ID NO: 3), SSGGGSGG (SEQ. ID NO: 8), SSGGGGSGGG (SEQ. ID NO: 9), TSGGGSG (SEQ. ID NO: 10), TSGGGGSGG (SEQ. ID NO: 11), SSGGGSGGSSG (SEQ. ID NO: 12), GGSGGTSGGGSG (SEQ. ID NO: 13), SGGTSGGGGSGG (SEQ. ID NO: 14), GGSGGTSGGGGSGG (SEQ. ID NO: 15), SSGGGGSGGGSSG (SEQ. ID NO: 16), SSGGGSGGSSGGG (SEQ. ID NO: 17), SSGGGGSGGGSSGGG (SEQ. ID NO: 18), and GGSGGTRPSTAATS (SEQ. ID NO: 19), and a polypeptide including a neutralizing domain of a self-protein growth factor, wherein said immunogenic polypeptide is separated from said polypeptide by said peptide spacer.
2. The recombinant protein according to claim 1, wherein said immunogenic polypeptide includes a cholera toxin B (CT-B) protein.
3. The recombinant protein according to claim 1, wherein said self-protein growth factor includes an epidermal growth factor (EGF).
4. The recombinant protein according to claim 1, wherein said neutralizing domain includes a B-loop of an epidermal growth factor (EGF).
5. The recombinant protein according to claim 1, wherein said self-protein growth factor includes a full length or part thereof of one or more growth factors selected from the group consisting of IGF-1, IGF-2, FGF1, FGF2, TGF-α, TGF-β, VEGF-A, VEGF-B, VEGF-C, VEGF-D, PDGF, NGF, EGF, HGF, BMP's, and IL's 1-6.
6. The recombinant protein according to claim 1, wherein said polypeptide includes a full length or neutralizing domain of at least two different growth factors.
7. The recombinant protein according claim 1, wherein said polypeptide includes a full length or neutralizing domain of one or more growth factors as a single domain or as two or more tandem repeats.
8. A process of preparing a multivalent molecule comprising: assembling multimers from one or more monomeric sub-units to form a synthetic protein including one or more growth factors or parts thereof, wherein the monomeric sub-units are the recombinant protein of claim 1.
9. The recombinant protein according to claim 1, wherein said peptide spacer is configured to reduce steric hindrance between said immunogenic polypeptide and said polypeptide.
10. The recombinant protein according to claim 1, wherein said immunogenic polypeptide includes a cholera toxin B (CT-B) protein.
11. The recombinant protein according to claim 1, wherein said growth factor is an epidermal growth factor (EGF).
12. An immunogenic composition, comprising: an immunogenic polypeptide; a peptide spacer selected from the group consisting of SSGGG (SEQ. ID NO: 4), GGSGG (SEQ. ID NO: 3), SSGGGSGG (SEQ. ID NO: 8), SSGGGGSGGG (SEQ. ID NO: 9), TSGGGSG (SEQ. ID NO: 10), TSGGGGSGG (SEQ. ID NO: 11), SSGGGSGGSSG (SEQ. ID NO: 12), GGSGGTSGGGSG (SEQ. ID NO: 13), SGGTSGGGGSGG (SEQ. ID NO: 14), GGSGGTSGGGGSGG (SEQ. ID NO: 15), SSGGGGSGGGSSG (SEQ. ID NO: 16), SSGGGSGGSSGGG (SEQ. ID NO: 17), SSGGGGSGGGSSGGG (SEQ. ID NO: 18), and GGSGGTRPSTAATS (SEQ. ID NO: 19); and a polypeptide including a neutralizing domain of a growth factor, wherein said immunogenic polypeptide is separated from said polypeptide by said peptide spacer.
13. The immunogenic composition of claim 12, wherein said growth factor is a human self-protein growth factor.
14. The immunogenic composition of claim 12, wherein said growth factor includes a full length or part thereof of one or more growth factors selected from the group consisting of IGF-1, IGF-2, FGF1, FGF2, TGF-α, TGF-β, VEGF-A, VEGF-B, VEGF-C, VEGF-D, PDGF, NGF, EGF, HGF, BMP's, and IL's 1-6.
15. The immunogenic composition of claim 14, wherein said growth factor includes a full length or part thereof of IGF-1, IGF-2, EGF, and combinations thereof.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The embodiments described in the present disclosure are illustrated in the figures of the accompanying drawings which are meant to be exemplary and not limiting, in which like references are intended to refer to like or corresponding parts, and in which:
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(31) HGF and TGF B1 were captured with α-HGF and α-TGF B1 antibodies, and CTB was detected;
(32) FGF2 was captured with α-CTB antibody and FGF2 detected;
(33) VEGF A/C was captured with (i) α-VEGF-A antibody and (ii) α-VEGF-C antibody, and CTB was detected in both cases;
(34) IGF1/2 was captured by α-IGF1 antibody in both cases, and detected with (i) α-CTB antibody and (ii) α-IGF2 antibody;
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DETAILED DESCRIPTION
(50) Detailed embodiments of the present recombinant proteins or vaccines are disclosed herein, however, it is to be understood that the disclosed embodiments are merely exemplary, which may be embodied in various forms. Therefore, specific functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the recombinant protein disclosed herein.
(51) The present disclosure provides a homogeneous recombinant protein for improving the presentation of the maximum number of growth factor epitopes, tumor antigen epitopes, and/or receptor binding sites as elements of an immunogenic recombinant protein. In one illustrative embodiment, a recombinant protein expressing all or portions of a cholera toxin B (CT-B), and a human epidermal growth factor (EGF), a tumor antigen, and/or a receptor is described. In alternative illustrative embodiments, the protein may express other immunogenic recombinant proteins that are modeled based upon known immunogenic proteins. It is contemplated within the scope of the disclosure that such recombinant proteins will be expressions of polypeptides that are highly immunogenic to the human immune system. Preferably, the recombinant proteins confer additional properties to the chimeric protein, for example, high expression yield and ease of manufacture, oral stability and the ability to cross from gut to blood stream, and/or previous safe use in humans.
(52) In an illustrative embodiment, the recombinant proteins disclosed herein may include or express a high proportion of a protein sequence derived from target self antigens, as a function of total molecular weight. This can be achieved, for example, by using a large protein model containing multiple growth factor epitopes. These growth factor epitopes can be multiple copies of whole or part of a single growth factor, or copies of whole or part of more than one different growth factor.
(53) According to the disclosure, the expressions of the growth factor epitopes should be folded allowing their natural conformation to be substantially retained and presented to components of the host immune system in such a way as to elicit a robust host immune response to said epitopes. Examples of suitable natural protein models to model an epitope supporting domain of a recombinant protein include, but are not limited to, cholera toxin B sub-unit, E. coli heat-labile LT and LT-II enterotoxin B subunits, veratoxin, pertussis toxin, C. jejuni enterotoxin, Shiga toxin, listeria toxin, tetanus toxoid, diphtheria toxoid, N. meningitidis I outer membrane protein, bacteriophage coat protein, adenovirus and other viral coat proteins. Alternatively, a non-self component of the protein can be small. As a minimum, the non-self sequence(s) should comprise about 9, 10, 11 or more amino acids in length, and include either entirely or in-part at least one human T-cell epitope. Alternatively, non-natural ‘synthetic’ polypeptides may be used that fulfill the requirements of conferring immunogenicity to the whole protein and allowing appropriate presentation of growth factor(s), receptors, tumor antigens or epitopes thereof to the host immune system.
(54) In an illustrative embodiment, the epitope supporting domain of the recombinant protein, whether derived from a natural or synthetic polypeptide sequence, should have the capacity to self-assemble into oligomeric multimers under appropriate chemicallenvironmental conditions, or to be reduced to monomers under alternative conditions. Ideally, multimerisation domains will assemble into stable multimers with a discreet number of sub-units, for example dimers, trimers, tetramers, pentamers, etc., such that a product of homogeneous size is generated. Examples of natural polypeptides include, but are not limited to, leucine zippers, lac repressor protein, streptavidin/avidin, cholera toxin B sub-unit, B sub-units of other ABs toxins, Pseudomonas trimerization domain, and viral capsid proteins.
(55) According to the disclosure the recombinant proteins, whether either growth factors or parts thereof, cellular receptors or parts thereof, tumor antigens or parts thereof, are related to broad range of either cellular pathways involved in chronic disease or cancers for growth factors and receptors and to broadest possible range of solid tumors for use of tumor antigens within the said synthetic proteins. The proteins are in the form of a recombinant protein and may be useful in treating chronic diseases, for example, breast, lung, bladder, ovarian, vulva, colonic, pulmonary, brain, colorectal, intestinal, head and neck, and esophagus cancers. As different tumor antigens can be expressed and multiple cellular receptors and growth factors over expressed in the said diseases, the proteins described hereunder can contain one or more different tumor antigens, one or more different receptors or growth factors of one or multiple cellular pathways associated with the disease. These proteins are called“multivalent.”
(56) In an illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing one or more epidermal growth factor (EGF) neutralizing domains is disclosed. The protein is in the form of a recombinant protein and may be useful in treating chronic diseases, for example, breast, lung, bladder, ovarian, vulva, colonic, pulmonary, brain, colorectal, head and neck, and esophagus cancers. In an illustrative embodiment, the protein is a recombinant protein expressing or including EGF sequences and CT-B sequences.
(57) In another illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing one fibroblast growth factor (FGF) is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including FGF sequences and CT-B sequences.
(58) In a further illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing one transforming growth factor-Beta 1 (TGF-β1) is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including TGF-β1 sequences and CT-B sequences.
(59) In yet another illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing one transforming growth factor-Beta 1 (TGF-β1) is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including TGF-β1 sequences and CT-B sequences.
(60) In one illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing one insulin-like growth factor-1 (IGF-1) is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including IGF-1 sequences and CT-B sequences.
(61) In another illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing one hepatocyte growth factor (HGF) is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including HGF sequences and CT-B sequences.
(62) In a further illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing one Insulin-like growth factor-1 (IGF-1) and one insulin-like growth factor-2 is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including IGF-1 sequences, IGF-2 sequences and CT-B sequences.
(63) In yet another illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing one vascular endothelial growth factor-A (VEGF-A) and one vascular endothelial growth factor-C (VEGF-C) is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including VEGF-A neutralizing domain sequences, VEGF-C sequences and CT-B sequences.
(64) To determine the appropriate coding region(s) of the HuEGF to express or include, the sequences and structures of EGF molecules from a range of organisms are analyzed. A table illustrating sequences and structures of EGF molecules from a range of organisms is described with reference to
(65) A structure of the human EGF molecule, including the EGF neutralizing domain, according to an illustrative embodiment is described with reference to
(66) A simplified line structure of the EGF molecule's cysteine pairs, including the EGF B-loop 200, according to an illustrative embodiment is described with reference to
(67) A structure of a modified recombinant protein molecule according to the disclosure expressing at least a portion of the EGF molecule, including the EGF neutralizing domain according to an illustrative embodiment is described with reference to
(68) Alanine is used because alanine is fairly ‘neutral’ in terms of functional characteristics and has the smallest side chain apart from glycine. Alanine is therefore considered the least likely residue to impart any non-native characteristics to the modified recombinant protein. It is contemplated within the scope of the disclosure that potentially any other residue could be used, or even no change made at all.
(69) In an illustrative embodiment, any part of the EGF molecule could be used from the region defined by residues Met21-Ala30 up to the entire EGF sequence. The sequences selected for expression in the recombinant EGF-CT-B proteins in the examples include all of the EGF sequence, and separately a region that is thought required for correct presentation of the neutralizing domain defined as a neutralizing domain in the context used, and doesn't include any other part of the EGF that is not considered necessary to achieve this.
(70) In another illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing a neutralizing domain of vascular endothelial growth factor-A (VEGF-A) is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including VEGF-A sequences and CT-B sequences. In an illustrative embodiment, the VEGF-A sequence will include the neutralizing domain comprising the sequence from Cys57 to Cys104 of the mature protein. In another illustrative embodiment, the sequence of VEGF-A will include one or more flanking residues extending up to Val14 and Lys108.
(71) In another illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing the ligand binding domain of TGF-Beta receptor II is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including TGFB-RII sequences and CT-B sequences. The TGFB-RII sequence will include any sequence of the extra-cellular domain between Thr23 and Gln166.
(72) In another illustrative embodiment, a protein comprised of a homogeneous recombinant protein expressing the ligand binding domain of the HGF receptor (c-Met) is disclosed. In an illustrative embodiment, the protein is a recombinant protein expressing or including HGF receptor sequences and CT-B sequences. Preferably, the HGF receptor sequence will include any sequence of the extra-cellular SEMA domain between Lys27 and Leu515.
Example I: ELISA Protocols
(73) In order to determine whether recombinant proteins, such as the synthetic EGF-CT-B proteins according to the disclosure, can display the EGF B-loop in the correct conformation, two commercial monoclonal antibodies (Santa Cruz Antibodies, Cat No's 10825 and 10827) that were known to block binding of EGF to the EGF receptor were obtained. Without being bound to any particular theory, it is postulated from a number of sources that binding to the EGF receptor is achieved in part via the region defined by residues Met21-Ala30.
(74) In an illustrative embodiment, 1 ug/ml and 2 ug/ml concentrations of mAb 10825 and mAb 10827 were used to bind a recombinant EGF (rEGF) protein in ELISA, and optical density (OD) was measured at 450 nm. The results are illustrated in a bar graph with reference to
(75) To assess recognition of residues Met21-Ala30, a plate was coated with about 100 ul/well protein (rEGF) at about 1 ug/ml and incubated at about 37° C. for about 1 h. The plate was washed twice with about 200 ul/well PBS-0.5% Tween (PBST), then twice with about 200 ul PBS. The plate was blocked with about 200 ul/well PBS-2% milk powder (MPBS) and incubated for about 1 hour at about 37° C. The plate was then washed twice with PBST and twice with PBS, as above. About 100 ul of the test antibodies were added at either about 1 ug/ml or about 2 ug/ml and incubated for about 1 hour at about room temp (RT). The plate was washed again as described above. Secondary, an antibody (HRP-labeled anti-mouse Fc-specific, Sigma product code A0168) was added at about 1/1000 dilution, about 100 ul/well and incubated for about 1 h at about RT. The plate was washed again as above, and developed with about 100 ul/well Sureblue TMB substrate until color developed (usually about 5-10 min). The reaction was stopped with about 50 ul/well IM H2SO4, and the plate was read at about 450 nm.
(76) Additionally, a competitive binding ELISA was carried out. In the second ELISA the binding of each of the mAb 10825 and mAb 10827 antibodies to rEGF was assessed in the presence of either free soluble peptide corresponding to the epitope of interest (peptide sequence MYIEALDKYA) or a control irrelevant peptide (peptide sequence SLAGSSGALSK). ELISAs with about 100 ul/well at about 1 ug/ml of mAb 10825 plus about 1 ug/ml of the free soluble peptide corresponding to the target epitope, about 1 ug/ml of mAb 10827 plus about 1 ug/ml of the free soluble peptide Met21-Ala30, about 1 ug/ml of mAb 10825 plus about 1 ug/ml of the control irrelevant peptide, and about 1 ug/ml of mAb 10827 plus about 1 ug/ml of the control irrelevant peptide were conducted.
(77) The optical density (OD) was measured at 450 nm. The results are illustrated in a bar graph with reference to
Example II: EGF Neutralizing Epitope Presentation
(78) To determine whether or not the recombinant protein EGF-CT-B vaccine expressing the EGF on a termini of the CT-B sequence interferes with or otherwise influences any of the desired inherent characteristics of the EGF domain(s), specifically the correct conformational presentation of the EGF Met21-Ala30 epitope, and the ability of CT-B monomers to assemble into multimers (pentamer rings) under appropriate physico-chemical conditions, six recombinant proteins were created expressing the entire EGF coding region on the CT-B sequence at either the N (Test 1-Test 3) or C-terminus (Test 4-Test 6).
(79) Test 1 and Test 4 include the recombinant protein EGF-CT-B vaccine expressing the full length EGF sequence directly on the CT-B domain. Test 2 and Test 5 include the synthetic EGF-CT-B vaccine expressing the full length EGF sequence separated from the CT-B domain by a short 3 amino acid peptide sequence. The recombinant protein EGF-CT-B vaccine expressing the EGF sequence on the N-terminal, includes SerGlyGly as the 3 amino acid peptide sequence, and includes a KpnI restriction site. The recombinant protein EGF-CT-B vaccine expressing the EGF sequence on the C-terminal, includes SerSerGly as the 3 amino acid peptide sequence, and includes a XhoI restriction site.
(80) Test 3 and Test 6 include the recombinant protein EGF-CT-B expressing the full length EGF sequence separated from the CT-B domain by a short 5 amino acid peptide sequence. The recombinant protein EGF-CT-B expressing the EGF sequence on the N-terminal, includes GlyGlySerGlyGly as the 5 amino acid peptide sequence, and includes a KpnI restriction site. The synthetic EGF-CT-B expressing the EGF sequence on the C-terminal, includes SerSerGlyGlyGly as the 5 amino acid peptide sequence, and includes a XhoI restriction site. The short 3 and 5 amino acid peptide sequences serve both to distance the growth factor domain from the CT-B sequence, and also to allow a degree of freedom of movement of one domain relative to the other, thus reducing any potential steric hindrance.
(81) Each of the six recombinant protein EGF-CT-B were cloned into a bacterial expression vector (pIMS147), such that the synthetic recombinant EGF-CT-B proteins could be expressed in E. coli periplasm, and purified by the inclusion of a C-terminal 6×His tag. Each recombinant EGF-CT-B sequence was expressed, purified, and quantified by means of protein gel/Bradford assay.
(82) The presentation of the EGF neutralizing epitope Met21-Ala30 in each of the six recombinant EGF-CT-B proteins was determined by ELISA. The recombinant EGF-CT-B proteins, including one terminal EGF domain were immobilized onto an ELISA plate. The EGF Met21-Ala30 epitopes were detected with the mAb 10827 antibody (Santa Cruz).
(83) The ELISA plate was coated with serial 2-fold dilutions of synthetic EGF-CT-B 6-His purified proteins and incubated at about 37° C. for about 1 hour. The plate was washed and blocked with about 2% MPBS, as described above. Washing involved pipetting about 200 ul PBS or PBST into each well, inverting the plate and flicking to empty the wells, and repeating. The mAb 10827 antibody was then added to all the wells at about 1 μg/ml and incubated at about room temperature for about 1 hour. The plate was washed once more and an anti-mouse Horse-Raddish Peroxidase (HRP) was added to the wells and incubated for about a further 1 hour. The plate was washed again and developed using SureBlue TMB.
(84) Upon adding the SureBlue TMB substrate, the HRP conjugated to the secondary antibody enzymatically processes the substrate to yield a blue product. The reaction was observed and monitored until it was decided that the color intensity has reached a sufficient level. (If color begins to appear in the control wells, which contain no primary antibody, then the reaction is stopped at this point). The reaction is stopped by addition of about 50 ul H2SO4 which destroys HRP activity. It also changes the color of the reaction product from blue to yellow. This can then be measured in a plate reader at about 450 nm absorbance.
(85) The results of the binding ELISAs are illustrated in a line graph with reference to
(86) In order to confirm that the synthetic recombinant EGF-CT-B protein included expressions of the EGF domain and the CT-B sequence, a second ELISA was performed whereby rather than adsorbing the recombinant protein directly onto the plates, the recombinant protein was instead captured using a rabbit anti-CT-B antibody (Antibodies On-Line), as shown in
Example III: EGF-CT-B Protein Multimer Assembly
(87) In order to examine the effect of expressing a structural domain comprising a growth factor on the termini of the CT-B derived recombinant protein on assembly of multimers from monomeric sub-units, synthetic proteins Test 1-Test 6 were run on an SDS-PAGE gel under native conditions (non-reduced, non-boiled). The synthetic recombinant EGF-CT-B proteins were then transferred onto a nitro-cellulose membrane by electro-blotting, and were probed using a rabbit anti-CT-B antibody (as described above in example II). Binding of a secondary HRP-labeled anti-rabbit antibody was detected via the light emitted using ECL substrate on autoradiograph film. As illustrated in
(88) In a separate experiment, duplicate samples of native (non-boiled or reduced) CT-B protein were incubated for 5 min. at a range of different pH values from pH 1.0 to 7.0. Following incubation, one of each duplicate sample was neutralized back to pH 7.0 for one hour. All samples were then run on an SDS-PAGE gel, Western blotted, and protein detected with anti-CTB antibody (
Example IV: Bivalent Synthetic EGF-CT-B Proteins
(89) In an illustrative embodiment, two additional synthetic recombinant EGF-CT-B proteins were created, in which i) a full length EGF gene is expressed at both the N- and C-termini, separated from the CT-B gene by the three amino acid sequence as described for Test-2 and Test-5 above, and designated ‘E2’, or ii) a truncated EGF including the Met21-Ala30 neutralizing epitope is expressed at both termini of the CT-B gene as above, and designated ‘B2’. Both recombinant proteins were cloned into the E. coli expression vector pIMS147 as described above. Both recombinant EGF-CT-B proteins were expressed and purified as described previously, and assayed for the presence of correctly folded CT-B domain and presentation of EGF neutralizing epitope Met21-Ala30 in the correct conformation. The results are illustrated in a line graph with reference to
(90) Further analysis involved running samples of purified E2 and B2 recombinant EGF-CT-B proteins on non-denaturing SDS-PAGE gels at pH 7.0 without first boiling the samples, and transferring to nitrocellulose membranes via electro-transfer. The transferred proteins were detected using the AbOL (Antibodies On-Line) anti-CT-B rabbit polyclonal antibody and an HRP-labeled anti-rabbit antibody. As illustrated in
Example V: EGF-CT-B Protein Sequence
(91) One example of a sequence of a synthetic recombinant EGF-CT-B protein is illustrated in
Example VI: EGF-CT-B Protein Sequence
(92) Another example of a sequence of a synthetic recombinant EGF-CT-B protein is illustrated in
Example VII: EGF-CT-B Protein Sequence
(93) Yet another example of a sequence of a recombinant EGF-CT-B protein is illustrated in
Example VIII: EGF-CT-B Protein Sequences Including Linkers
(94) In other illustrative embodiments, additional recombinant EGF-CT-B proteins including one or more linkers or spacers are disclosed herein. One or more of the embodiments described above include EGF fused to CT-B at one or both termini of the CT-B such that one gene ran directly into the next. These resulting recombinant or chimeric proteins essentially included EGF fused directly to CT-B. In other illustrative embodiments, the EGF and CT-B components of the chimeric protein are effectively separated by 3 or 5 amino acids, which form a flexible spacer or linker between the two domains. The following amino acids that can be used as linkers included but are not limited to the following: SSG, SSGGG, SGG, GGSGG, and GGGGS.
(95) The addition of the linkers can reduce interferences, for example, from steric hindrance, and aid in the formation of pentamers by the CT-B domain. The linkers also enabled unique restriction sites to be introduced within the linkers to allow subsequent manipulation of the genetic constructs. In this example, eight constructs (T1-T6, E2, and B2) are described, having the sequences listed in the Table illustrated in
(96) Western blot analysis of the constructs T1-T6, E2, and B2 was performed and are described below in connection with
(97) The lowest bands correspond to monomers, the next up to dimers etc. As B2 includes truncated EGFs, it appears to be smaller than E2, which is illustrated by B2 being lower on the Western blot.
(98) A similar result is found for the constructs T1-T6, although the numbers and proportions of oligomers vary from construct to construct. Initially, it appeared that proteins with EGF on the N-terminus including the amino acid linkers might give a higher proportion of pentamer. However, subsequently it was found that the proportion of pentamer varied from batch to batch.
(99) Since it was initially postulated that fusion at one or other terminus favors pentamerization, two tandem fusions in addition to the E2 construct were constructed and are illustrated in
(100) In an illustrative embodiment, the amino acid linker lengths at the N-terminus and the C-terminus were extended to determine whether or not the amino acid linker length at each end yields pentamer only, or perhaps that one end, the N-terminus or the C-terminus, yields a higher proportion of pentamer. Referring to
(101) Referring to
(102) A comparative Western blot analysis was also performed on the monovalent ‘T’ constructs with the extended linkers, and is illustrated in
(103) When the linker spacers are inserted, they can actually be cloned in either of two directions, giving quite different sequences. Wherever possible, sufficient clones were sequenced to find one with the insertion in the desired direction. In the case of T3LL-Rev, initially we only had a clone with the desired linker length (i.e. 14 aa's) but with the insert in the ‘wrong’ orientation. It does serve to illustrate how the precise sequences of these linkers isn't necessarily critical, at least as far as acting as a physical spacer. The actual linker sequence of T3LL-Rev would be GGSGGTRPSTAATS. (underlined=inverted section).
(104) As illustrated in the Western blot illustrated in
(105) In contrast, as illustrated in
(106) Based on this data, the tandem N-terminus fusion of EGF to CT-B appears to be of significant interest. Additionally, the first linker (between the two EGF domains) may be extended to attempt to prevent the truncation/proteolysis described above with the E2N construct, and to allow flexibility when introducing alternative growth factors. The Sequence for the N-terminus FUSION of EGF to CT-B with the extended first linker) is as follows:
(107) TABLE-US-00001 HHHHHHIEGRNSDSECPLSHDGYCLHDGVCMYI EALDKYACNCVVGYIGERCQYRDLKWWELRGGSGG TSGGGGSGGTPQNITDLCAEYHNTQIHTLNDKIFSY TESLAGKREMAIITEKNGATFQVEVPGSQHIDSQ KKAIERMKDTLRIAYLTEAKVEKLCVWNNKTPHA IAAISMAN
(108) While the homogeneous recombinant proteins expressing or incorporating EGF B-loop epitopes have been described and illustrated in connection with certain embodiments, many variations and modifications will be evident to those skilled in the art and may be made without departing from the spirit and scope of the disclosure.
Example IX: Bi-Specific IGF1-EGF-CTB Protein (a)
(109) In order to establish the feasibility of targeting more than one growth factor with a single synthetic recombinant protein, a gene encoding the human insulin-like growth factor 1 (IGF1) was synthesized including short flanking regions to enable cloning into the construct E2N described in example VIII. Briefly, the N-terminal EGF gene was excised from the vector by digesting the DNA with the restriction endonucleases Nco1 and Xho1. It was then replaced with the similarly digested human IGF1 gene using methods familiar to those skilled in the art. The resulting DNA vector was sequenced to confirm that it encoded the required recombinant gene in such a way as to allow the recombinant protein to be expressed as designed. The sequence of the novel recombinant protein is illustrated in
(110) Subsequently, the protein generated by the expression of the aforementioned vector was analyzed by ELISA to demonstrate that both growth factors can be simultaneously displayed to components (i.e. antibodies) of the mammalian immune system. Briefly, wells of an ELISA plate were coated with an appropriate dilution of anti-CTB antibody and then blocked with PBS containing 2% milk powder as described previously. Samples of the recombinant protein were applied to the plate and incubated for 1 hour at room temperature. After washing, different wells prepared as described were then incubated with 1/1000 (or as per supplier's recommendations) of either i) mouse anti-EGF antibody AbOL 10827 or ii) rabbit anti-human IGF1 2o antibody. After washing, the wells were incubated with an appropriate dilution of i) HRP-labeled anti-mouse antibody or ii) HRP-labeled anti-rabbit antibody and then developed as described previously. As illustrated in
Example X: Bi-Specific IGF1-EGF-CTB Protein (b)
(111) In order to demonstrate that bi-specific recombinant proteins can be generated using the natural characteristic of CTB to form oligomers, the IGF gene described in example IX was modified by PCR using techniques familiar to those skilled in the art to enable it to be cloned into the T5 construct, replacing the EGF gene, The resulting recombinant protein included IGF sequences C-terminal to CTB sequences, and separated by a 3 amino acid linker (
(112) Samples of the above recombinant protein were combined separately with equal (molar) amounts of i) T2 protein and ii) T5 protein. Each of the mixtures was adjusted to pH 3.0 by the addition of buffered 10 mM Tris-HCL as required and incubated at 4° C. for 15 min to dissociate any oligomers present. The protein mixtures were then neutralized, and incubation continued for 60 min in order to encourage oligomerization. To detect the presence of hetero-oligomers, wells of an ELISA plate were coated with either mouse anti-EGF antibody or rabbit anti-IGF antibody, and blocked. After washing, IGF-CTB/T2 mix and IGF-CTB/T5 mix were applied separately to either wells coated with anti-EGF antibody or with anti-IGF antibody, and incubated for 60 min at room temperature.
(113) After washing, antibody specific to the growth factor not targeted by the coating antibody was added and incubated for 60 min. Thus, rabbit anti-IGF antibody was applied to wells coated with mouse anti-EGF antibody, and vice-versa. After washing to remove unbound 2o antibody, HRP-labeled anti-mouse or HRP-labeled anti-rabbit antibody was applied as appropriate to target the 2o antibody. The results are illustrated in
Example XI: Diverse Growth Factor Presentation
(114) In order to further demonstrate the flexibility of the present invention, a panel of recombinant proteins were generated that included sequence derived from CTB together with additional sequence derived from one or more of a range of growth factors and representing a range of domains of varying size according to
Example XII: Growth Factor Receptor Presentation
(115) In order to demonstrate that the technology described in the present disclosure is applicable to the functional display of proteins other than growth factors, recombinant proteins including sequences derived from growth factor receptors and CTB were generated, and shown to present such sequences in a natural conformation in conjunction with CTB sequences. DNA encoding the protein sequence of human TGF-beta1 was cloned upstream of the CTB gene. by replacing the EGF coding DNA from the T3LL clone using standard techniques familiar to those practiced in the art. This construct was used to generate a recombinant protein including both human TGF-beta1 and CTB sequences (
(116) The simultaneous presentation of both TGF-Beta R2 and CTB sequences on a single recombinant protein was established by capture ELISA. Briefly, wells of an ELISA plate were coated with i) mouse anti-CTB antibody or ii) goat anti-TGF Beta R2 antibody and blocked with PBS containing milk powder. Samples of the recombinant protein according to
(117) In order to demonstrate that both TGF-Beta1 and TGF Beta R2 were both presented separately with CTB sequences in a native configuration, the interaction between TGF beta1 and its natural receptor was determined by ELISA. Briefly, wells of an ELISA plate were coated with mouse anti-CTB antibody as blocked. The wells were then contacted with the recombinant protein containing human TGF-beta1 and CTB sequences as described in
Example XIII: Immune Responses of Mice to Recombinant Protein Formulations
(118) In another experiment groups of mice were immunized with recombinant proteins including sequences from CTB and one or more growth factors according to the present disclosure in order to assess the effects of various formulations on immune responses of said mice. Six groups of mice, each comprising six mice were immunized, with a different recombinant protein formulation according to the schedule described below.
(119) Unless otherwise stated, mice were immunized with 25 μg recombinant protein in 75 μl buffer, emulsified in 75 μl montanide adjuvant. Immunogens were administered via i.m. injection at day 0 and day 14. Serum samples were taken at day 0 (pre-immunization) and day 28 and were analyzed for the presence of IgG antibodies against the growth factor sequences contained within the immunizing recombinant protein. The groups of mice were immunized with the following antigens:
(120) Group 1: SB1, 75 μl (25 μg) recombinant protein including human IGF and CTB sequences according to
(121) Group 2: SB2, 75 μl (25 μg) recombinant protein including human EGF and CTB sequences as described in example VIII and referred to as T3LL, emulsified with 75 μl montanide;
(122) Group 3: SB3, 75 μl (25 μg) recombinant protein including human IGF, human EGF and CTB sequences according to
(123) Group 4: SB4, 37.5 μl (12.5 μg) SB1 and 37.5 μl (12.5 μg) SB2 combined by the method as described in example X and including oligomers containing both IGF-CTB and EGF-CTB, emulsified with 75 μl montanide;
(124) Group 5: SB5, 75 μl (25 μg) SB1, as for Group 1, except emulsified with 20 μl Matrix-M adjuvant; and
(125) Group 6: SB6, 37.5 μl (12.5 μg) SB1 emulsified with 37.5 μl montanide, followed after 5 min by 37.5 μl (12.5 μg) SB2 emulsified with 37.5 μl montanide and administered via a different location.
(126) Immediately prior to, and 14 days after immunization, blood samples were taken and serum analyzed by ELISA for the presence and relative titres of IgG antibodies against the growth factor component of the recombinant protein immunizing antigens. ELISA plates were coated with commercially available recombinant human IGF or EGF at 1 μg/ml concentration. After blocking and washing, serum from subject mice at various dilutions was applied to wells and incubated for 1 hour at room temperature. Un-bound antibody and other proteins were removed by washing, and bound mouse IgG detected with HRP-labeled anti-mouse antibody.
(127) All six groups included animals that raised a specific immune response to the growth factor component of the immunogenic recombinant chimeric proteins. It is evident that stronger responses are seen to EGF than to IGF throughout, including groups where sequences from only one growth factor was included (Groups 1 and 2,
(128) The use of Matrix-M rather than Montanide as adjuvant (Group 5 compared to Group 1,
(129) Groups 3, 4 and 6 received proteins that included sequences from both EGF and IGF, the difference being the formulation or administration. Group 3 mice, receiving recombinant protein that included both EGF and IGF sequences on each protein molecule, all responded to EGF though two of the six did not show an α-IGF response (
Example XIV: Generic Single-Step Purification
(130) A simple first-stage purification process is desired that can be applied to any and all of the immunogenic recombinant proteins detailed in the present disclosure. Ideally, the purification will not require the inclusion of an affinity tag such as hexa-histidine, MBP, FLAG etc. The recombinant proteins of the present disclosure are related in that they all include at least some sequence derived from the Vibrio cholera CT-B toxin sub-unit, or a synthetic functional equivalent. It is envisaged that purification could be achieved by the use of monoclonal or polyclonal antibodies, however monoclonal antibodies are expensive to produce. Polyclonal antibodies are less expensive, however it is likely that variations in performance will be seen between batches from the same animal, and between individual animals. Immuno-affinity purification also requires harsh conditions such as low pH to elute target protein that can adversely affect the target protein, and will limit the re-use of the affinity matrix. It also involves the introduction of additional protein into the production process, which is preferably avoided.
(131) In the native CT holotoxin, the toxin binds to mono-ganglioside Gm1 (
(132) The binding of CTB to Gm1 is known to involve a terminal galactose moiety on the branched glyco-molecule Gm1 binding to two adjacent CTB sub-units. It is therefore envisaged that galactose immobilized to a suitable solid support would provide a generic means to purifying the recombinant proteins of the present disclosure. To assess the applicability of this approach, the gene encoding CTB was cloned into a bacterial protein expression vector designed for periplasmic protein recovery using techniques familiar to those practiced in the art, and transformed into various strains of E. coli bacteria. Galactose-sepharose resin (
(133) The galactose sepharose resin was washed with 200 mM NaCl, 50 mM Tris HCl, 5 mM EDTA pH 7.5 (TEN buffer) according to manufacturer's instructions. NaCl, Tris-HCl pH 7.5 and EDTA were added to the conditioned media and periplasmic fractions to a final concentration of 200 mM NaCl, 50 mM Tris-HCl and 5 mM EDTA. 0.5 ml washed galactose sepharose was added to each conditioned media and periplasmic fraction, and incubated with agitation at 4° C. for 2-3 h. The resin was recovered into BioRad columns and washed with 30 bed volumes of ice-cold TEN buffer. The bound protein was eluted by re-suspending the resin in 0.5 ml 1 M galactose in PBS and incubating for 10 min. The column was drained and the eluate retained for analysis. The elution step was repeated several times, and fractions analyzed for the presence of CTB. Almost all of the expressed CTB protein was found in the culture media. Samples of pre-purification conditioned media and periplasmic fraction, together with pooled column eluates containing purified CTB (from the media) were analysed by SDS-PAGE and compared with His-tagged CTB purified by IMAC (
Additional Embodiments
(134) In another illustrative embodiment, a vaccine comprised of a homogeneous recombinant protein for improving the presentation of and increasing the number of tumor antigen epitopes as elements of a synthetic immunogenic recombinant protein is disclosed herein. In one illustrative embodiment, a vaccine formed from a recombinant protein expressing all or portions of a polypeptide sequence and a tumor antigen is described herein.
(135) In an illustrative embodiment, the recombinant proteins disclosed herein may include or express a high proportion of a protein sequence derived from tumor antigens and/or epitopes thereof, as a function of total molecular weight. These tumor antigen epitopes can be multiple copies of whole or part of a single tumor antigen, or copies of whole or part of more than one different tumor antigen.
(136) In an illustrative embodiment, the recombinant protein is an immunogenic protein molecule expressing one or more sequences that fold into a physical structure, for example expressing one or more sequences of a cholera toxin B (CT-B) protein from Vibrio cholera or a synthetic equivalent, and expressing one or more sequences of one or more tumor antigens or parts thereof.
(137) In an illustrative embodiment, the sequence of the tumor antigen may include a sequence of a Prostate Specific Antigen (PSA) or part thereof. In other illustrative embodiments, the tumor antigen may include a full length or part thereof of one or more of the following tumor antigens, including, but not limited to, PSA, and other tumor antigens.
(138) In another illustrative embodiment, a protein comprised of a homogeneous recombinant protein for improving the presentation of and increasing the number of receptor binding sites as elements of a immunogenic recombinant protein is disclosed herein. In one illustrative embodiment, a recombinant protein expressing all or portions of a polypeptide sequence and a receptor is described herein.
(139) In an illustrative embodiment, the recombinant proteins disclosed herein may include or express a high proportion of a protein sequence derived from receptors and/or binding sites thereof, as a function of total molecular weight. These binding sites can be multiple copies of whole or part of a single receptor, or copies of whole or part of more than one different receptor.
(140) In an illustrative embodiment, the recombinant protein is an immunogenic protein molecule expressing one or more sequences that fold into a physical structure, for example expressing one or more sequences of a cholera toxin B (CT-B) protein from Vibrio cholera or a synthetic equivalent, and expressing one or more sequences of one or more receptors or parts thereof.
(141) In an illustrative embodiment, the sequence of the receptor may include a sequence of a Human Epidermal growth factor Receptor 2 (Her2) or part thereof and/or a Human Epidermal growth factor Receptor 3 (Her3) or part thereof. In other illustrative embodiments, the receptor may include a full length or part thereof of one or more of the following receptors, including, but not limited to, Her2, Her3, and other receptors.
(142) In other illustrative embodiments, the recombinant protein is an immunogenic protein molecule expressing one or more sequences that fold into a physical structure, for example expressing one or more sequences of a CT-B or a synthetic modified variant, and expressing various combinations of one or more sequences of one or more growth factors or parts thereof, one or more sequences of one or more tumor antigens or parts thereof, and one or more sequences of one or more receptors or parts thereof.
(143) In an illustrative embodiment, the recombinant protein includes expressions or sequences of one or more growth factors or parts thereof and one or more sequences of one or more tumor antigens or parts thereof. In one embodiment, the recombinant protein includes one or more sequences of a CT-B or a synthetic modified variant, a PSA or part thereof, and an IGF-1 or part thereof.
(144) In another illustrative embodiment, the recombinant protein includes expressions or sequences of one or more growth factors or parts thereof and one or more sequences of one or more receptors or parts thereof. In one embodiment, the recombinant protein includes one or more sequences of a CT-B or a synthetic modified variant, a Her2 or part thereof, and an IGF-1 or part thereof. In another embodiment, the recombinant protein includes one or more sequences of a CT-B or a synthetic modified variant, a Her2 or part thereof, a Her2 or part thereof, and a PDGF or part thereof.
(145) In another illustrative embodiment, the recombinant protein includes expressions or sequences of one or more tumor antigens or parts thereof and one or more sequences of one or more receptors or parts thereof.
(146) In yet another illustrative embodiment, the recombinant protein includes expressions or sequences of one or more growth factors or parts thereof, one or more sequences of one or more tumor antigens or parts thereof, and one or more sequences of one or more receptors or parts thereof.
(147) In any of the embodiments described above, in addition to expressing one or more copies of a single tumor antigen, receptor, and/or growth factor, presented as a single tumor antigen, receptor, and/or growth factor or part thereof per physical site, and/or as chains of repetitive tumor antigen, receptor, and/or growth factor sequences (for example, n=1 to 10). The recombinant proteins according to the disclosure may also include expressions of one or more neutralizing domains or binding sites from two or more different tumor antigens, receptors, and/or growth factors present as single or as chains at different positions within the sequences of the recombinant proteins. For example, the recombinant proteins may include expressions or sequences of a full length or a portion of two to four different tumor antigens, receptors, and/or growth factors, and/or a full length or a portion of one or more tumor antigens, receptors, and/or growth factors as single epitopes or binding sites or as two or more tandem repeats.
(148) The resulting proteins are single polypeptides expressing a tumor antigen, receptor, and/or growth factor or one or more epitopes or binding sites thereof within the sequence of the recombinant proteins. In an illustrative embodiment, the sequences of the recombinant proteins expresses one or more portions of a CT-B sequence and presents the tumor antigen, receptor, and/or growth factor expression(s) including at least one or more expression(s) of epitopes or binding sites thereof on a surface of the immunogenic recombinant proteins in a natural conformation.
(149) According to the disclosure, the expressions of the tumor antigen epitopes, receptor binding sites, and/or growth factor epitopes should be folded allowing their natural conformation to be substantially retained and presented to components of the host immune system in such a way as to elicit a robust host immune response. Examples of suitable natural protein models include, but are not limited to, cholera toxin B sub-unit, listeria, tetanus toxoid, diphtheria toxoid, bacteriophage coat protein, adenovirus and other viral coat proteins. Alternatively, non-natural ‘synthetic’ polypeptides may be used that fulfill the requirements of conferring immunogenicity to the whole protein and allowing appropriate presentation of tumor antigen epitopes, receptor binding sites, and/or growth factor epitopes to the host immune system.
(150) Adjuvant
(151) Certain illustrative embodiments as provided herein include recombinant proteins according to the disclosure within vaccine compositions and immunological adjuvant compositions, including pharmaceutical compositions, that contain, in addition to recombinant proteins at least one adjuvant, which refers to a component of such compositions that has adjuvant activity. An adjuvant having such adjuvant activity includes a composition that, when administered to a subject such as a human (e.g., a human patient), a non-human primate, a mammal or another higher eukaryotic organism having a recognized immune system, is capable of altering (i.e., increasing or decreasing in a statistically significant manner, and in certain preferred embodiments, enhancing or increasing) the potency and/or longevity of an immune response. In certain illustrative embodiments disclosed herein a desired antigen and or antigens contain within a protein carrier, and optionally one or more adjuvants, may so alter, e.g., elicit or enhance, an immune response that is directed against the desired antigen and or antigens which may be administered at the same time or may be separated in time and/or space (e.g., at a different anatomic site) in its administration, but certain illustrative embodiments are not intended to be so limited and thus also contemplate administration of recombinant protein in a composition that does not include a specified antigen but which may also include but is not limited to one or more co-adjuvant, an imidazoquinline immune response modifier.
(152) Accordingly and as noted above, adjuvants include compositions that have adjuvant effects, such as saponins and saponin mimetics, including QS21 and QS21 mimetics (see, e.g., U.S. Pat. No. 5,057,540; EP 0 362 279 B1; WO 95/17210), alum, plant alkaloids such as tomatine, detergents such as (but not limited to) saponin, polysorbate 80, Span 85 and stearyl tyrosine, one or more cytokines (e.g., GM-CSF, IL-2, IL-7, IL-12, TNF-alpha, IFN-gamma), an imidazoquinoline immune response modifier, and a double stem loop immune modifier (dSLIM, e.g., Weeratna et al., 2005 Vaccine 23:5263).
(153) Detergents including saponins are taught in, e.g., U.S. Pat. No. 6,544,518; Lacaille-Dubois, M and Wagner H. (1996 Phytomedicine 2:363-386), U.S. Pat. No. 5,057,540, Kensil, Crit. Rev Ther Drug Carrier Syst, 1996, 12 (1-2):1-55, and EP 0 362 279 B1. Particulate structures, termed Immune Stimulating Complexes (ISCOMS), comprising fractions of Quil A (saponin) are haemolytic and have been used in the manufacture of vaccines (Morein, B., EP 0 109 942 B1). These structures have been reported to have adjuvant activity (EP 0 109 942 B1; WO 96/11711). The haemolytic saponins QS21 and QS17 (HPLC purified fractions of Quil A) have been described as potent systemic adjuvants, and the method of their production is disclosed in U.S. Pat. No. 5,057,540 and EP 0 362 279 B1. Also described in these references is the use of QS7 (a non-haemolytic fraction of Quil-A) which acts as a potent adjuvant for systemic vaccines. Use of QS21 is further described in Kensil et al. (1991. J. Immunology 146:431-437). Combinations of QS21 and polysorbate or cyclodextrin are also known (WO 99/10008). Particulate adjuvant systems comprising fractions of QuilA, such as QS21 and QS7 are described in WO 96/33739 and WO 96/11711. Other saponins which have been used in systemic vaccination studies include those derived from other plant species such as Gypsophila and Saponaria (Bomford et al., Vaccine, 10(9):572-577, 1992).
(154) Escin is another detergent related to the saponins for use in the adjuvant compositions of the embodiments herein disclosed. Escin is described in the Merck index (12.sup.th Ed.: entry 3737) as a mixture of saponin occurring in the seed of the horse chestnut tree, Aesculus hippocastanum. Its isolation is described by chromatography and purification (Fiedler, Arzneimittel-Forsch. 4, 213 (1953)), and by ion-exchange resins (Erbring et al., U.S. Pat. No. 3,238,190). Fractions of escin (also known as aescin) have been purified and shown to be biologically active (Yoshikawa M, et al. (Chem Pharm Bull (Tokyo) 1996 August; 44(8): 1454-1464)). Digitonin is another detergent, also being described in the Merck index (12th Ed., entry 3204) as a saponin, being derived from the seeds of Digitalis purpurea and purified according to the procedure described by Gisvold et al., J. Am. Pharm. Assoc., 1934, 23, 664; and Rubenstroth-Bauer, Physiol. Chem., 1955, 301, 621.
(155) Other adjuvants or co-adjuvants for use according to certain herein disclosed embodiments include a block co-polymer or biodegradable polymer, which refers to a class of polymeric compounds with which those in the relevant art will be familiar. Examples of a block co-polymer or biodegradable polymer that may be included in a vaccine composition or a immunological adjuvant include Pluronic® L121 (BASF Corp., Mount Olive, N.J.; see, e.g., Yeh et al., 1996 Pharm. Res. 13:1693),
(156) Certain further illustrative embodiments contemplate immunological adjuvants that include but are not limited to an oil, which in some such embodiments may contribute co-adjuvant activity and in other such embodiments may additionally or alternatively provide a pharmaceutically acceptable carrier or excipient. Any number of suitable oils are known and may be selected for inclusion in vaccine compositions and immunological adjuvant compositions based on the present disclosure. Examples of such oils, by way of illustration and not limitation, include squalene, squalane, mineral oil, olive oil, cholesterol, and a mannide monooleate.
(157) Immune response modifiers such as imidazoquinoline immune response modifiers are also known in the art and may also be included as adjuvants or co-adjuvants in certain presently disclosed embodiments.
(158) As also noted above, one type of adjuvant or co-adjuvant for use in a vaccine composition according to the disclosure as described herein may be the aluminum co-adjuvants, which are generally referred to as “alum.” Alum co-adjuvants are based on the following: aluminum oxy-hydroxide; aluminum hydroxyphosphoate; or various proprietary salts. Alum co-adjuvants are be advantageous because they have a good safety record, augment antibody responses, stabilize antigens, and are relatively simple for large-scale production. (Edelman 2002 Mol. Biotechnol. 21:129-148; Edelman, R. 1980 Rev. Infect. Dis. 2:370-383.)
(159) Pharmaceutical Compositions
(160) In certain illustrative embodiments, the pharmaceutical composition is a vaccine composition that comprises both the recombinant protein according to the disclosure and may further comprise one or more components, as provided herein, that are selected from TLR agonist, co-adjuvant (including, e.g., a cytokine, an imidazoquinoline immune response modifier and/or a dSLIM) and the like and/or a recombinant expression construct, in combination with a pharmaceutically acceptable carrier, excipient or diluent.
(161) Illustrative carriers will be nontoxic to recipients at the dosages and concentrations employed. For vaccines comprising recombinant protein, about 0.01 .mu.g/kg to about 100 mg/kg body weight will be administered, typically by the intradermal, subcutaneous, intramuscular or intravenous route, or by other routes.
(162) It will be evident to those skilled in the art that the number and frequency of administration will be dependent upon the response of the host. “Pharmaceutically acceptable carriers” for therapeutic use are well known in the pharmaceutical art, and are described, for example, in Remington's Pharmaceutical Sciences, Mack Publishing Co. (A. R. Gennaro edit. 1985). For example, sterile saline and phosphate-buffered saline at physiological pH may be used. Preservatives, stabilizers, dyes and even flavoring agents may be provided in the pharmaceutical composition. For example, sodium benzoate, ascorbic acid and esters of p-hydroxybenzoic acid may be added as preservatives. In addition, antioxidants and suspending agents may be used.
(163) The pharmaceutical compositions may be in any form which allows for the composition to be administered to a patient. For example, the composition may be in the form of a solid, liquid or gas (aerosol). Typical routes of administration include, without limitation, oral, topical, parenteral (e.g., sublingually or buccally), sublingual, rectal, vaginal, and intranasal (e.g., as a spray). The term parenteral as used herein includes iontophoretic sonophoretic, passive transdermal, microneedle administration and also subcutaneous injections, intravenous, intramuscular, intrastemal, intracavemous, intrathecal, intrameatal, intraurethral injection or infusion techniques. In a particular embodiment, a composition as described herein (including vaccine and pharmaceutical compositions) is administered intradermally by a technique selected from iontophoresis, microcavitation, sonophoresis or microneedles.
(164) The pharmaceutical composition is formulated so as to allow the active ingredients contained therein to be bioavailable upon administration of the composition to a patient. Compositions that will be administered to a patient take the form of one or more dosage units, where for example, a tablet may be a single dosage unit, and a container of one or more compounds of the invention in aerosol form may hold a plurality of dosage units.
(165) For oral administration, an excipient and/or binder may be present. Examples are sucrose, kaolin, glycerin, starch dextrins, sodium alginate, carboxymethylcellulose and ethyl cellulose. Coloring and/or flavoring agents may be present. A coating shell may be employed.
(166) The composition may be in the form of a liquid, e.g., an elixir, syrup, solution, emulsion or suspension. The liquid may be for oral administration or for delivery by injection, as two examples. When intended for oral administration, preferred compositions contain one or more of a sweetening agent, preservatives, dye/colorant and flavor enhancer. In a composition intended to be administered by injection, one or more of a surfactant, preservative, wetting agent, dispersing agent, suspending agent, buffer, stabilizer and isotonic agent may be included.
(167) A liquid pharmaceutical composition as used herein, whether in the form of a solution, suspension or other like form, may include one or more of the following carriers or excipients: sterile diluents such as water for injection, saline solution, preferably physiological saline, Ringer's solution, isotonic sodium chloride, fixed oils such as squalene, squalane, mineral oil, a mannide monooleate, cholesterol, and/or synthetic mono or digylcerides which may serve as the solvent or suspending medium, polyethylene glycols, glycerin, propylene glycol or other solvents; antibacterial agents such as benzyl alcohol or methyl paraben; antioxidants such as ascorbic acid or sodium bisulfite; chelating agents such as ethylenediaminetetraacetic acid; buffers such as acetates, citrates or phosphates and agents for the adjustment of tonicity such as sodium chloride or dextrose. The parenteral preparation can be enclosed in ampoules, disposable syringes or multiple dose vials made of glass or plastic. An injectable pharmaceutical composition is preferably sterile.
(168) In a particular embodiment, a pharmaceutical or vaccine composition of the invention comprises a stable aqueous suspension of less than 0.2 um and further comprises at least one component selected from the group consisting of phospholipids, fatty acids, surfactants, detergents, saponins, fluorodated lipids, and the like.
(169) It may also be desirable to include other components in a vaccine or pharmaceutical composition, such as delivery vehicles including but not limited to aluminum salts, water-in-oil emulsions, biodegradable oil vehicles, oil-in-water emulsions, biodegradable microcapsules, and liposomes. Examples of additional immunostimulatory substances (co-adjuvants) for use in such vehicles are also described above and may include N-acetylmuramyl-L-alanine-D-isoglutamine (MDP), glucan, IL-12, GM-CSF, gamma interferon and IL-12.
(170) While any suitable carrier known to those of ordinary skill in the art may be employed in the pharmaceutical compositions of this invention, the type of carrier will vary depending on the mode of administration and whether a sustained release is desired. For parenteral administration, such as subcutaneous injection, the carrier preferably comprises water, saline, alcohol, a fat, a wax or a buffer. For oral administration, any of the above carriers or a solid carrier, such as mannitol, lactose, starch, magnesium stearate, sodium saccharine, talcum, cellulose, glucose, sucrose, and magnesium carbonate, may be employed. Biodegradable microspheres (e.g., polylactic galactide) may also be employed as carriers for the pharmaceutical compositions of this invention.
(171) Pharmaceutical compositions may also contain diluents such as buffers, antioxidants such as ascorbic acid, low molecular weight (less than about 10 residues) polypeptides, proteins, amino acids, carbohydrates including glucose, sucrose or dextrins, chelating agents such as EDTA, glutathione and other stabilizers and excipients. Neutral buffered saline or saline mixed with nonspecific serum albumin are exemplary appropriate diluents. Preferably, product may be formulated as a lyophilizate using appropriate excipient solutions (e.g., sucrose) as diluents.
(172) In an illustrative embodiment, the epitope or receptor supporting domain of the recombinant protein, whether derived from a natural or synthetic polypeptide sequence, should have the capacity to self-assemble into oligomeric multimers under appropriate chemicallenvironmental conditions, or to be reduced to monomers under alternative conditions. Ideally, multimerisation domains will assemble into stable multimers with a discreet number of sub-units, for example dimers, trimers, tetramers, pentamers, etc., such that a product of homogeneous size is generated. Examples of natural polypeptides include, but are not limited to, leucine zippers, lac repressor protein, streptavidin/avidin, cholera toxin B sub-unit, Pseudomonas trimerization domain, and viral capsid proteins.
(173) In an illustrative embodiment, a process of preparing a multivalent molecule is disclosed. In this illustrative embodiment, the process includes assembling multimers from monomeric sub-units to form a synthetic protein including one or more tumor antigens, receptors, and/or a growth factors or parts thereof.
(174) In another illustrative embodiment, a process of preparing a vaccine formulation is disclosed. In this illustrative embodiment, the process includes mixing one or more single monovalent multimers together preparing a multivalent vaccine including a recombinant protein including one or more tumor antigens, receptors, and/or a growth factors or parts thereof.
(175) In yet another illustrative embodiment, a process for treating a patient is disclosed. In this illustrative embodiment, the process includes administering separately to the patient one or more monovalent, one tumor antigen, receptor, and/or growth factor, recombinant proteins in a same day or at alternate days or times during a vaccination period.
(176) While the recombinant protein is described as including or expressing one or more of all or a portion of at least one sequence of the tumor antigens, the growth factors, and/or the receptors, and the CT-B sequence, the recombinant protein may include the natural CT-B sequence or a sequence substantially similar to the natural CT-B sequence and/or a synthetic sequence.
(177) While the recombinant protein is described as including or expressing the CT-B sequence, the recombinant protein may include or express a derivation of the CT-B sequence or a sequence that is substantially similar to the CT-B sequence.
(178) While the homogeneous recombinant proteins expressing or incorporating one or more tumor antigens, growth factors, and/or receptors have been described and illustrated in connection with certain embodiments, many variations and modifications will be evident to those skilled in the art and may be made without departing from the spirit and scope of the disclosure. The disclosure is thus not to be limited to the precise details of methodology or construction set forth above as such variations and modification are intended to be included within the scope of the disclosure.