Anti CD30 chimeric antigen receptor and its use

Abstract

In a first aspect, the present disclosure relates to genetically modified T-cells having a chimeric antigen receptor for use in adoptive cell therapy for treating CD30+ cancer in a subject need thereof. In particular, the present disclosure relates to a T-cell containing a specific chimeric antigen receptor being toxic to CD30+cancer cells while being non-toxic to CD30+ non-cancer cells. In a further aspect, the present disclosure relates to a specific chimeric antigen receptor and the nucleic acid molecule encoding the receptor as well as vectors and cells containing the same. Finally, the present disclosure relates to the use of the chimeric antigen receptor for use in improving persistence and amplification of lymphocyte containing the same and the use of specific peptides for improving persistence and amplification of genetically modified lymphocytes expressing the same.

Claims

1. A method of adoptive cell therapy for treating CD30.sup.+ cancer in a subject in need thereof comprising the step of administering to said subject a T-cell with a chimeric antigen receptor whereby the chimeric antigen receptor contains at least the following domains starting from the N-terminus to the C-terminus: an HRS3 scFv peptide having the sequence as set forth in SEQ ID No. 2, optionally a spacer domain, a transmembrane domain of CD28, a cytoplasmic signaling domain, wherein the cytoplasmic signaling domain is selected from the CD3 zeta signaling domain of SEQ ID No. 7, a Fc epsilon receptor gamma-signaling domain of SEQ ID No. 8 or a CD28 signaling domain, wherein said T-cell with the chimeric antigen receptor is toxic to CD30.sup.+ cancer cells, while being non-toxic to CD30.sup.+ non-cancer activated T cells, B cells and/or stem cells in said subject, and wherein said CD30.sup.+ cancer cells include one or more of CD30.sup.+ leukemia cells and CD30.sup.+ lymphoma cells.

2. The method for adoptive cell therapy for treating CD30.sup.+ cancer in a subject in need thereof according to claim 1, wherein the T-cell with a chimeric antigen receptor further comprise a leader sequence located N-terminally to the anti-CD30 single chain antibody domain.

3. The method for adoptive cell therapy for treating CD30.sup.+ cancer in a subject in need thereof according to claim 1 wherein in the T-cell with a chimeric antigen receptor the spacer domain is an IgG1 CH2CH3 domain of SEQ. ID. No. 5 or homologs thereof having at least 70% identity therewith.

4. The method of claim 3 wherein the spacer domain is a mutated IgG.sub.1CH2CH3 domain according to SEQ. ID. No. 5.

5. The method for adoptive cell therapy for treating CD30.sup.+ cancer in a subject in need thereof according to claim 1, wherein in the T-cell with a chimeric antigen receptor the chimeric antigen receptor is a polypeptide of SEQ. ID. No. 3.

6. The method for adoptive cell therapy for treating CD30.sup.+ cancer in a subject need thereof according to claim 1 wherein the CD30.sup.+ cancer is any one of Hodgkin's lymphoma, anaplastic large cell lymphoma, acute lymphocytic leukaemia, cutaneous lymphoma, mycosis fungoides, lymphoproliferative diseases, systemic mastocytosis, teratocarcinoma, stem cell derived malignancies, cancer stem cells.

7. The method of adoptive cell therapy for treating CD30.sup.+ cancer in a subject in need thereof according to claim 1 wherein the CD30.sup.+ cancer is selected from the group consisting of Hodgkin's lymphoma, non-Hodgkin's B cell lymphoma, mycosis fungoides or Szary lymphoma.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1: Modular composition of the molecule CAR #1138 with Seq. ID. No.3 encoded by a nucleic acid of Seq. ID. No. 4.

(2) FIG. 2: Engineered human T-cells express the CAR #1138. Human peripheral T-cells were isolated from the blood of a healthy donor and retrovirally engineered by transduction of vector #1138. After 12 hrs cells were tested for #1138 CAR expression by two colour FACS according to SOP_tumorgenetics_FACS using a PE-labelled polyclonal goat anti-human IgG Fc antibody and the FITC-labelled murine anti-human CD3 monoclonal antibody UCHT1.

(3) FIG. 3: Engineered T-cells eliminate CD30.sup.+ lymphoma cells and less CD34.sup.+ CD30.sup.+ hematopoietic stem cells. T-cells with CAR #1138, T-cells without CAR after shame-transduction (T-cells #1138 negative) and non-modified T-cells (w/o) were co-cultivated with allogeneic CD34.sup.+ hematopoetic stems cells, induced to express CD30, and CFSE-labeled CD30.sup.+ Myla cells for 24 hrs. Cells were stained with the anti-CD34-PE monoclonal antibody (mAb) AC136 (20 l). Counting standard (5 l/test) and 7 AAD (5 l/test) were added and cells were analyzed by FACS setting counts for 1,000 events of standard beads. The test was done in triplicates and the total number of target cells was determined.

(4) FIG. 4: T-cells with #1138 and without #1138 CAR, respectively, were co-cultivated with allogeneic CD34.sup.+ hematopoietic stem cells and CFSE-labeled CD30.sup.+ Myla cells for 24 hrs. Cells were stained with the anti-CD34-PE mAb AC136 (20 l). Counting standard (5 l/test) and 7-AAD (5 l/test) were added and cells were analyzed by FACS by setting counts for 1,000 events of standard beads. The number of dead cells (7-AAD.sup.+) in each target population was determined and diplayed as % dead cells of total target cells using the following formula: percent of dead target cells=(number of 7-AAD.sup.+ target cells/number of total target cells)* 100. The test was performed in triplicates.

(5) FIG. 5: CD30.sup.+ T- and B-cells persist in the peripheral blood of humanized SCID mice in presence of anti-CD30 CAR T-cells #1138. SCID mice were engrafted with the human hematopoietic system to harbor human B- and T-cells in the peripheral blood. At day 0 human T-cells of the same donor and engineered with the #1138 CAR were adoptively transferred by i.v. injection. Peripheral blood CD30.sup.+ CD4.sup.+ T-cells (A) and CD30.sup.+ CD19.sup.+ B-cells (B) at day 5 before treatment and day +50 after treatment with anti-CD30 CAR T-cells #1138 were recorded by flow cytometry.

(6) FIG. 6: T-cells with anti-CD30 CAR #1138 preferentially accumulate during in vitro culture. Peripheral blood lymphocytes were engrafted with the respective CARs. After transduction cells were cultured in Xvivo15 medium supplemented with 10% FCS and IL-2 (500 U/ml). Medium was replaced once a week, IL-2 was added every 3rd day. CD3.sup.+ T-cells were recorded for CAR expression utilizing FITC-conjugated anti-mouse and PE-conjugated anti-human IgG1 Fc antibodies at the indicated time after start of culture.

(7) FIG. 7: FIG. 7a shows a flow chart of the experimental design. In FIG. 7b target cell lysis of autologous B-cells by anti-CD30 CAR T-cells according to the present invention is shown.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

(8) The inventors aim to provide genetically engineered T-cells containing a chimeric antigen receptor whereby said T-cells display a toxic activity on CD30.sup.+ cancer cells while being non-toxic to CD30.sup.+ non-cancer cells in said subject. That is, in a first aspect, the present invention relates to T-cells with a chimeric antigen receptor for use in adoptive cell therapy for treating CD30.sup.+ cancer in particular, CD30.sup.+ lymphoma or CD30.sup.+ leukemia cells in a subject in need thereof whereby the chimeric antigen receptor contains at least the following domains starting from the N-terminus to the C-terminus: an anti-CD30 single chain antibody domain, in particular, HRS3-scFv of SEQ ID No. 2 or a homolog having binding specificity to CD30 thereof having at least 70% identity with SEQ ID No. 2; optionally a spacer domain; a transmembrane domain; and a cytoplasmatic signalling domain; characterized in that said T-cell with the chimeric antigen receptor is toxic to CD30.sup.+ cancer cells, in particular, CD30.sup.+ leukaemia cells or CD30.sup.+ lymphoma cells while, being non-toxic to CD30.sup.+ non-cancer cells in said subject.

(9) In this connection, the term CD30.sup.+ cancer cells refers to malignant cells or neoplastic cells expressing the CD30 molecule.

(10) Further, the term CD30.sup.+ non-cancer cells refers to benign (healthy) cells expressing the CD30 molecule, like activated T-cells, B-cells or stem cells.

(11) The terms non-tumor cells and tumor cells as well as non-cancer cells and cancer cells are used herein interchangeably unless otherwise defined.

(12) As used herein, the term comprise or comprising as well as the terms contain or containing refers to the embodiment of consist or consisting.

(13) The term homolog as used herein refers to molecules, either DNA or polypeptides, having a sequence homology of a certain amount, namely of at least 70%, like at least 80%, 90%, 95%, 96%, 97%, 98%, 99% of the nucleic acid sequence or the amino acid sequence it is referred to. Homology refers to the magnitude of identity between two sequences. Homolog sequences have the same or similar characteristics, in particular, have the same or similar property of the sequence as identified. For example, the homolog of the HRS3 scFv sequence of Seq. ID. No. 2 has the same or similar binding specificity to the CD30 molecule as it is the case for the HRS3 scFv molecule. Further, homologs include nucleic acid molecules encoding the same peptide but may vary in its sequence due to the degeneracy of the genetic code. Further, identify refers to presence of identical amino acid or nucleic acid molecules in the order as described for the sequence it refers to. That is, in case of at least 90% identity, 90% or more of the nucleic acid and amino acid molecules, respectively, are identical at the respective positions. Unless otherwise identified, the terms homology and identity are used herein interchangeably. In an embodiment, the homolog is a homolog of the HRS3 scFv peptide of SEQ ID No. 2 binding specifically to the same epitope recognized by the HRS3 scFv peptide of SEQ ID No. 2.

(14) In addition, the term genetically engineered refers to cells being manipulated by genetic engineering. That is, the cells contain a heterologous sequence which does not naturally occur in said cells. Typically, the heterologous sequence is introduced via a vector system or other means for introducing nucleic acid molecules into cells including liposomes. The heterologous nucleic acid molecule may be integrated into the genome of said cells or may be present extra-chromosomally, e.g. in the form of plasmids. The term also includes embodiments of introducing genetically engineered, isolated CAR polypeptides into the cell.

(15) Generally, CARs are fusion proteins, consisting of an extracellular antibody type recognition domain fused to intracellular T-cell signalling proteins. Typically, the ectodomain containing the antigen recognition region comprises a signal peptide and an antigen recognition unit. According to the present invention, the ectodomain comprises an anti CD30 single chain domain. It is preferred, that said single chain domain is a single chain domain selected from HRS3 scFv of SEQ. ID. No. 2 or homologs thereof binding specifically to CD30 having at least 70% identity with SEQ ID No. 2. Further, the single chain domain may be derived from other anti-CD30 antibodies like HRS4 or Ki-4. Said antibodies have the same binding specificity to CD30 as it is the case for the HRS3 antibody, namely binding to the same epitope of CD30.

(16) The ectodomain may be spaced apart from the transmembrane domain by the presence of a spacer domain. Said optional spacer domain links the antigen-binding domain to the transmembrane domain and it is preferred that said transmembrane domain is flexible enough to allow the antigen binding domain to orient in different directions to facilitate antigen recognition.

(17) The transmembrane domain is typically a hydrophobic alpha helix that spans the membrane. Other transmembrane domains can also be used. Finally, the endodomain represents the signalling domain in the cytoplasmic part of the CAR.

(18) It has been recognized that a T-cell containing the CAR as described, namely, containing a CAR starting from the N-terminus to the C-terminus having the following composition: an anti-CD30 single chain antibody domain, optionally, a spacer domain, a transmembrane domain, a cytoplasmic domain is able to display toxic activity distinctively between CD30.sup.+ cancer cells and CD30.sup.+ non-cancer cells. Thus, the T-cells of the present invention overcome the problems known in the art of cytotoxic effects on both cancer CD30.sup.+ cells and healthy CD30.sup.+ cells, e.g. as described in the art.

(19) In an embodiment of the present invention, the CAR comprises a leader sequence being located N-terminally to the anti CD30 single chain antibody domain.

(20) In addition, in another embodiment, the anti-CD30 single chain antibody domain is a HRS3 scFv peptide, in particular, of SEQ. ID. No. 2. It has been recognized herein that an anti-CD30 single chain antibody fragment of the variable region (scFv), in particular, of HRS3, allows to display the desired activity, namely, being toxic to CD30.sup.+ cancer cells while being non-toxic to CD30.sup.+ non-cancer cells.

(21) In another embodiment, the spacer domain of the CAR molecule is an IgG.sub.1 hinge-CH2CH3 domain of SEQ. ID. No. 5 or homologs thereof having at least 70% identity therewith, preferably, the spacer domain is a mutated IgG.sub.1 hinge-CH2CH3 domain according to SEQ. ID. No. 5.

(22) In some embodiments, between the spacer domain and the transmembrane domain a linker may be located. For example, in the CAR of Seq. ID. No.3 a linker of 4 amino acids is located between the spacer domain and the transmembrane domain.

(23) Further, another embodiment relates to a T-cell with a chimeric antigen receptor wherein the transmembrane domain is derived from the CD28 molecule, e.g. the transmembrane domain of the CD28 molecule lacking the Ick domain of SEQ. ID. No. 6

(24) The signalling domain or endodomain or intracellular domain which are used herein interchangeably, contains a CD3 zeta or FcEpsilon receptor (IgE receptor) gamma chain signalling chain or a co-stimulatory domain. For example, the intracellular domain is a CD3 zeta signalling domain of SEQ. ID. No. 7 or a homolog thereof having at least 70% homology. In another embodiment, the intracellular domain is the Fc epsilon receptor gamma signalling domain of SEQ. ID. No. 8 or a homolog thereof having at least 70% identity. The signalling domain is responsible for the activation of the cytotoxic activity in T-cells or interferon-gamma secretion by T-cells, respectively.

(25) The CAR molecule may be a so-called second generation CAR molecule. Second generation CAR molecules have improved signalling domains additionally containing a second signalling domain, e.g. derived from CD28, CD134 (OX40) or CD137 (4-1BB). Third generation CAR molecules contain a combined co-stimulatory signalling domain, e.g., CD28 combined with CD137 or CD134.

(26) An overview about the CAR molecules is provided e.g. in Gilham D. E. et al., Trends in Molecular Medicine, 2012, 18(7), 377-384.

(27) In a preferred embodiment of the present invention, the T-cell is a T-cell with a chimeric antigen receptor wherein the chimeric antigen receptor is a polypeptide of SEQ. ID. No. 3. Said CAR is also referred to herein as #1138.

(28) The anti-CD30 CAR #1138 is expressed on the surface of T-cells and is composed in the extracellular part of the anti-CD30 single chain fragment of variable region (scFv) antibody HRS3 and the modified human IgG1 CH2CH3 domain as spacer between scFv and the trans-membrane domain. The modification of the IgG1 domain consists of point mutations to convert the wild-type amino acid sequence PELLGGP X.sub.13 MISRT (Seq. ID. No. 9) to PPVA-GP X.sub.13 MIART (Seq. ID. No. 10) which reduces unintended binding of the CAR Fc domain to Fc receptors on other cells like innate immune cells which would unintendedly mediate their activation and the activation of the CAR T-cells. The transmembrane and intracellular membrane proximal part of CAR #1138 is derived from human CD28 and is fused to the intracellular part of human CD3zeta. The CD28 sequence is mutated at P560>A560, P563>A563, P564>A564 (Kofler et al., Mol. Ther. 19, 760-767 (2011). Thereby the CD28 binding site for the Ick kinase is destroyed with the consequence that activation of the Ick signalling pathway and subsequent CAR mediated IL-2 secretion is prevented. Pre-clinical models imply that Treg cell mediated repression of CAR T-cell effector functions is reduced under these conditions.

(29) As demonstrated in the examples, the T-cells (either CD4.sup.+ or CD8.sup.+ T-cells) act differently on CD30.sup.+ cells, namely, CD30.sup.+ cancer cells are killed while CD30.sup.+ non-cancer cells remain alive in presence of T-cells with #1138 CAR.

(30) As an example, T-cells expressing the #1138 CAR are non toxic against healthy human CD30.sup.+ CD34.sup.+ hematopoetic stem cells whereas CD30.sup.+ lymphoma cells are eliminated.

(31) Moreover, as demonstrated in the example, the T-cells containing the #1138 CAR according to the present invention do not show toxic activity toward healthy human B- and T-cells in a mouse model. No significant autoimmune activity towards autologous healthy cells and no worse side effects occurred. In addition, lymphocyte immune response against pathogens was not altered allowing a cellular immune protection against the tested pathogen.

(32) In a further aspect, the present invention relates to the use of the T-cell with a chimeric antigen receptor according to the present invention in adaptive cell therapy for treating CD30.sup.+ cancer in a subject in need thereof. For instance the CD30.sup.+ cancer may be Hodgkin's lymphoma, anaplastic large cell lymphoma, acute lymphocytic leukaemia, cutaneous lymphoma, mycosis fungoides, lymphoproliferative diseases, systemic mastocytosis, teratocarcinoma, stem cell derived malignancies, or cancer stem cells or others.

(33) That is, surprisingly T-cells with the chimeric antigen receptor according to the present invention allows to treat CD30.sup.+ cancer in a subject in need thereof without harming the non-cancer CD30.sup.+ cells present in the subject to be treated. In contrast to previous observations with a tremendous variety of CARs having different antigen binding domains, the anti-CD30 antibody domain allows to eliminate malignant CD30.sup.+ cells while benign CD30.sup.+ cells are not affected.

(34) In a further aspect, the present invention relates to the polypeptide of SEQ. ID. No. 3 representing the CAR polypeptide denoted #1138 herein, or a homolog thereof having at least 90% identity whereby said polypeptide or its homolog when being expressed in a T-cell is a chimeric antigen receptor displaying a toxic effect on CD30.sup.+ cancer cells while being non-toxic on CD30.sup.+ non-cancer cells. For example, the polypeptide of Seq. ID. No. 3 is encoded by the nucleic acid sequence of Seq. ID. No. 4.

(35) The polypeptide is composed of the HRS3-scFv single chain domain of anti-CD30 antibody, a spacer domain being a mutated IgG1 hinge-CH2CH3 domain, a transmembrane domain derived from CD28, in particular, a CD28 derived transmembrane domain lacking Ick domain, and the intracellular domain of CD3 zeta.

(36) In addition, the present invention provides nucleic acid molecules comprising the nucleic acid sequence encoding the polypeptide according to the present invention. Furthermore, vectors are provided comprising the nucleic acid sequence according to the present invention encoding the polypeptide as described. The skilled person is well aware of suitable vector systems and vectors, in particular, vectors allowing transfection and transduction of eukaryotic cells, in particular, T-cells.

(37) Moreover, the present invention provides a cell, cell line or a host cell containing the vector according to the present invention or a nucleic acid molecule according to the present invention. Preferably, said cell, cell line or host cell is a T-cell, e.g., a CD4.sup.+ T-cell or a CD8.sup.+ T-cell.

(38) Further, the present invention provides a kit or system containing the vector according to the present invention, the cell, cell line or host cell according to the present invention, or the polypeptide according to the present invention or a nucleic acid molecule according to the present invention or mixtures thereof for use in the production of T-cells expressing the chimeric antigen receptor. The kit or system according to the present invention may contain further components including means for introducing the vector or polypeptide on nucleic acid molecules into the cells. The skilled person is well aware of suitable means for doing so.

(39) Moreover, the present invention relates to a chimeric antigen receptor as defined herein for use to improve persistence and proliferation of any genetically engineered lymphocyte expressing said chimeric antigen receptor #1138 or homologs thereof. That is, the present inventors surprisingly realized that in contrast to the broad variety of other chimeric antigen receptors, the chimeric antigen receptor #1138 according to the present invention confers an improved persistence and amplification of the genetically engineered lymphocytes as demonstrated in the examples. Hence, the clinically relevant shortcoming of so far known CAR T-cells is overcome where the persistence of the engineered T-cells in the subject was too short and the number of engineered T-cells rapidly dropped.

(40) Finally, the present invention provides a HRS3 scFv peptide, and homologs thereof having the same property with respect to the epitope identified by the scFv of HRS3. That is, e.g. the antibodies HRS4 and Ki-4 bind to the same epitope. Thus, scFv of HRS4 and scFv of Ki-4 likely have the same activity with respect to this invention. In addition, nucleic acid sequences encoding the said peptides are provided. Said peptides and nucleic acids are suitable for use to improve persistence and amplification of any genetically engineered lymphocyte expressing said peptide when said scFv peptide is part of a chimeric receptor or fused to a chimeric antigen receptor of any other specificity expressed by the genetically engineered lymphocyte. That is, combining the HRS3 scFv peptide, for example, the HRS3 scFv peptide of SEQ ID No. 2, e.g. encoded by the sequence of Seq. ID. No. 1, with a CAR molecule having additionally a different antigen binding specificity, improves the persistence and amplification of said engineered lymphocytes.

(41) The present invention is further described by way of examples. Said examples illustrate the invention further without limiting the same thereto.

EXAMPLES

Preparation of the Test Item

(42) The retroviral vector coding for the #1138 CAR was produced according to SOP-GL-VectProd using a Galv pseudotyped envelope. In summary vector particle production was done transiently on the human embryonic kidney cell line 293T after Polyfect mediated DNA transfection. Vector particles were pseudotyped with Galv. No vector titer was determined.

(43) Transduction of human blood lymphocytes was done according to standard techniques (Cheadle, E. J., et al., Chimeric antigen receptors for T-cell based therapy. Chapter 36, in: Antibody engineering: methods and protocols, 2nd Edition, Ed. P. Chames, Meth. Mol. Biol. 907, 645-666 (2012), doi: 10.1007/978-1-61779-974-7_36). In summary human lymphocytes were transduced with a 2-day supernatant from transfected 293T cells for 2 days. The CAR #1138 was expressed by 20-35% of human T-cells as measured at day 2 by flow cytometry using an antibody directed to the extracellular IgG1 CH2 CH3 domain of the CAR. For comparison the CAR #1175, see Hombach A, et al., Gene Ther. 2010 October; 17(10):1206-13. doi: 10.1038/gt.2010.91. Epub 2010 Jun. 17, was expressed on 17-30% of human T-cells as measured by the same procedure.

(44) CD4.sup.+ and CD8.sup.+ T-cells which express the CAR #1138 on the cell surface can be recorded by use of the 9G10 antibody which binds specifically the CAR HRS3 scFv domain. T-cells engineered with the #1138 CAR bind specifically to CD30 expressing cells and become activated indicated by increased secretion of cytokines including IFN-, by increase in proliferation and in cytolysis of CD30.sup.+ target cells. Noteworthy, only background levels of IL-2 are secreted when T-cells are stimulated by the CAR #1138. IL-2, however, is secreted in physiological amounts when T-cells are stimulated by their physiological TCR and CD28. Activation of the T-cells #1138 is antigen-specific as defined by the specificity of the CAR since CD30.sup. cells do not trigger T-cell activation. Soluble CD30, which accumulates in the serum of CD30.sup.+ lymphoma patients, does not block CAR mediated T-cell activation in concentrations up to 10 g/ml [Hombach A, et al., Cancer Res. 1998 Mar. 15;58(6)1116-9]. This is due to the fact that the CAR must be cross-linked by binding the multiple copies of the targeted antigen in order to trigger T-cell activation which can only occur when CD30 is immobilized on surfaces or expressed on the surface of target cells but does not occur when the CD30 protein is present in solution.

Example 1: Activity of CAR #1138 Modified T-cells toward CD30.SUP.+.Tumor and Healthy Cells

Engineering of T-cells with CAR #1138

(45) Engraftment of human peripheral T-cells with the #1138 CAR was assessed by two colour flow cytometry 12 hrs after transduction. FIG. 2 shows a dot blot analysis of CAR engineered T-cells. The number of T-cells with #1138 CAR expression was 16.5% of all T-cells.

Purification of T-cells with CAR #1138 and Control T-cells

(46) T-cells #1138 were cultivated for 60 hrs, labelled with the anti-human IgG-Fc-FITC, antibody which binds to the CAR, and the anti-CD3-PE antibody, which identifies the T-cells, and sorted using the FACSAria III cell sorter. Gates were set for CD3.sup.+ CAR #1138.sup.+ and CD3.sup.+ CAR #1138.sup.T-cells. Aliqouts of sorted cells were re-analyzed by FACS. The purity of CD3.sup.+#1138.sup.+ and CD3.sup.+#1138.sup. T-cells was 94.4% and 99.6%, respectively.

Isolation of Allogeneic CD34.SUP.+ Hematopoietic Stem Cells

(47) CD34.sup.+cells were isolated from peripheral blood of a volunteer donor upon mobilization with GM-CSF by density centrifugation and magnetic cell sorting (MACS). Cells were labelled with an anti-CD34 PE-conjugated mAb and aliquots of fractionated and unsorted cells were analyzed by FACS. The purity of isolated CD34.sup.+ cells was 94.4%.

CFSE-Labeling of Myla Cells

(48) Myla cells were labelled with 1.25 M CFSE and mixed with isolated CD34.sup.+ hematopoietic stem cells. CD34.sup.+ cells which were identified by anti-CD34-PE mAb and CFSE.sup.+ Myla cells can clearly be discriminated and both populations can separately be analyzed for viability.

Redirected Toxicity of T-cells with #1138 CAR towards CD30.SUP.+ Lymphoma Cells versus CD30.SUP.+ CD34.SUP.+ Hematopoietic Stem Cells

(49) CD30.sup.+ MyLa lymphoma cells together with CD30.sup.+ CD34.sup.+ healthy hematopoietic stem cells were co-incubated with T-cells engineered with anti-CD30 CAR #1138. As controls same CD30.sup.+ cells were co-incubated with T-cells without CAR (T-cells #1138 negative) derived from the same donor and cell preparation.

(50) The total number of target cells was determined by FACS and standardized by using a counting standard. CD34.sup.+ CD30.sup.+ hematopoietic stem cells were identified by staining with the monoclonal anti-CD34-PE antibody and lack of CSFE label which is different to CFSE-stained Myla cells. The test was done in triplicates and the data are summarized in FIG. 3. The number of CD34.sup.+ hematopoietic stem cells does not decrease in presence of T-cells without CAR (w/o), with CAR (T-cells #1138) or in the presence of T-cells lacking the CAR after the transduction procedure (T-cells #1138 negative). In contrast to CD34+CD30.sup.+ healthy cells, the number of CD30.sup.+ CFSE-labelled Myla cells substantially decreased due to CAR T-cell mediated killing (T-cells #1138) in addition to the expected allo-reactivity of T-cells (T-cells #1138 negative).

(51) To determine toxicity of T-cells CAR #1138 against CD30.sup.+ healthy and tumor cells, the number of dead target cells was determined in a direct fashion by means of flow cytometry. CD34.sup.+ CD30.sup.+ healthy cells were identified by the anti-CD34-PE antibody and discriminated from CFSE-labelled Myla lymphoma cells. Viable and dead target cells were determined by staining with 7-AAD. Data are summarized in FIG. 4.

Conclusions

(52) The toxicity of T-cells with the anti-CD30 CAR #1138 against healthy human CD30.sup.+ CD34.sup.+ hematopoietic stem cells was tested in comparison to targeting CD30.sup.+ lymphoma cells. T-cells from a healthy donor were engineered to express the #1138 CAR and T-cells without CAR from the same transduction batch were purified by cell sorting. The procedure was used to compare CAR mediated specific toxicity versus any un-specific toxicity induced by the transduction process itself. We recorded toxicity of purified T-cells #1138 for reactivity towards CD34.sup.+ allogeneic hematopoietic stem cells. Moreover, we recorded toxicity against CD30.sup.+ lymphoma cells simultaneously to toxicity against CD30.sup.+ CD34.sup.+ hematopoietic stem cells in the same assay by mixing the differently labelled target cells. The procedure allows to estimate direct and bystander toxicity in the same assay. The observation time for both the test group and the control group was 24 hrs.

(53) We found that the number of CFSE-labelled CD30.sup.+ Myla lymphoma cells specifically decreased when co-incubated with T-cells #1138 compared to co-incubation with #1138 negative T-cells. In line with that, the number of dead Myla target cells substantially increased upon co-incubation with T-cells #1138. In contrast, neither the absolute number of CD34.sup.+ healthy hematopoietic stem cells decreased nor did increase the number of dead CD34.sup.+ cells. Notable, we did not observe any direct or bystander toxicity against CD34.sup.+ hematopoietic stem cells although there occurs specific killing of CD30.sup.+ tumor cells by T-cells #1138 in the near vicinity of CD34.sup.+ CD30.sup.+ cells. Taken together T-cells with CAR #1138 did not show toxicity against healthy CD30.sup.+ CD34.sup.+ hematopoietic stem cells while specific toxicity toward CD30.sup.+ lymphoma cells.

Example 2: No Toxic Activity of CAR #1138 Engineered T-cells toward Healthy Human B- and T-cells in a Mouse Model

Dose Selection

(54) Human CD34.sup.+ hematopoietic stem cells were isolated from cord blood. New born Rag2.sup./31 common gamma chain.sup./31 mice were transplanted with 310.sup.5 CD34.sup.+ hematopoietic stem cells to engraft the human hematopoietic system. Successfully engrafted animals were transplanted with 2.510.sup.6 T-cells per mouse by a single injection into the tail vein.

Animals/Animal Maintenance

(55) Species: Mouse

(56) Strain/Stock: Rag2.sup./ cy.sup./

(57) Selection of species: The T- and B-cell deficient mouse model was used to engraft the human hematopoietic system; the reconstituted hematopoietic system closely mimics the human situation.

Identification of Animals

(58) TABLE-US-00001 TABLE 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 A- A- A- B- B- B- C- C- C- C- D- D- D- D- E- W- E- E- E- E- E- w1 w2 m1 w1 w2 m1 w1 w2 m1 m3 w1 m1 m1 m2 w1 m1 m2 m3 m4 m5 m6 Table 1: A-E = breeding group; m = male w = female; 1-6 mouse number

Transplantation of Human Hematopoiesis

(59) Rag2.sup./31 cy.sup./31 mice were engrafted with isolated human CD34.sup.+ hematopoietic stem cells from cord blood (SOP-RepopCD34, Appendix 6) and monitored for successful establishment of mature human lymphocytes after 5 weeks by flow cytometric recording of human CD45.sup.+ and CD4.sup.+ CD45.sup.+ T-cells in the peripheral blood.

Experimental Groups

(60) The animals were allocated to three test groups according to the Study Plan. The following groups were employed.

(61) TABLE-US-00002 TABLE 2 Group 1: (#1138 + 9G10) E-m2 left and right CD3+ cells, #1138 C-m3 (left) CD3+ cells, #1138 E-m6 (left) CD3+ cells, #1138 Group 2: (#1138) E-m4 (none) CD3+ cells, #1138 E-m5 (right) CD3+ cells, #1138 E-w1 (none) CD3+ cells, #1138 Group 3: (#1175) B-w1 (none) CD3+ cells, #1175 CD3+ cells, #1175 CD3+ cells, #1175
Adoptive cell therapy of animals with human hematopoiesis: i.v. tail vein injection of CD3.sup.+ T-cells with #1138 CAR into Rag2.sup./31 cy.sup./31 recipient mice with established autologous human hematopoiesis; control: transplantation of CD3.sup.+ T-cells with #1175 CAR.

Engraftment of Human Hematopoietic Cells in Rag2.SUP./31 cy.SUP./31 Recipient Mice

(62) Engraftment of the human CD34.sup.+ hematopoietic stem cell transplant and subsequent establishment of human hematopoiesis in the peripheral blood of mice was assessed by flow cytometric recording of human CD4.sup.+ and CD45.sup.+ cells 5 weeks after transplantation. The human hematopoietic system engrafted in 12/21 mice indicated by human CD4.sup.+ CD45.sup.+ T-cells in the peripheral blood. Mock-engrafted and non-treated Rag2.sup./31 cy.sup./31 mice do not harbour these cells. Litter mice A, B, C, D and E were engrafted with the same donor of CD34.sup.+ cord blood cells each. Only mice which successfully engrafted were used for adoptive cell therapy.

Expression of CAR #1138 by Engineered Human T-cells

(63) Human CD3.sup.+ T-cells (from the same donor as of the CD34.sup.+ cells) were ex vivo engineered to express the CD30-specific CAR #1138 or as control the CEA-specific CAR #1175. CAR #1175 harbors the CEA-specific scFv BW431/26 instead of the CD30-specific scFv HRS3 of CAR #1138 and was used as control throughout the study. CAR expression on human CD3.sup.+ T-cells was recorded by flow cytometric detection of both the extracellular human IgG spacer domain of the CAR and human CD3.

(64) CAR engineered T-cells were transferred to the corresponding mouse with the autologous hematopoietic system by i.v. injection (2.510.sup.6 T-cells with CAR per mouse).

Toxicity of T-cells with #1138 CAR In Vivo

(65) 1. Peripheral Blood Counts and Body Weight

(66) No apparent abnormalities were observed in the test group during the observation period. The percentage of lymphocytes (approx. 70%), monocytes (approx. 10%) and granulocytes (approx. 20-25%) in the cellular compartment of the peripheral blood of the test group did not differ from those observed in the control animals which did not receive T-cells or received T-cells with the control CAR #1175.

(67) The number of CD30.sup.+ T- and B-cells in the peripheral blood of mice in presence or absence of anti-CD30 T-cells # 1138 or anti-CEA T-cells #1175 as control were recorded by flow cytometry on day 5 before T-cell therapy and on day 7, 14, 22, 29, 36, 43, 50 after T-cell therapy.

(68) No alteration in the number of CD30.sup.+CD4.sup.+ T-cells and CD30.sup.+CD19+ B-cells in presence of T-cells #1138 was recorded after adoptive cell therapy during the 7 week observation period compared to day 5 before T-cell therapy. The number of CD30.sup.+CD4.sup.+ T-cells was the same compared to mice which received CEA-specific T-cells #1175 as control.

(69) The body weight of individual mice was weekly determined. We did not record any substantial alteration in the body weight of individual mice during the observation time. Moreover, no differences between the experimental groups were recorded.

(70) 2. No Toxicity upon CAR #1138 Stimulation In Vivo

(71) We challenged the anti-CD30 CAR T-cells #1138 in vivo by administration of irradiated 9G10 hybridoma cells which produce the anti-idiotypic antibody 9G10 directed against the HRS3 scFv domain of the CAR #1138. The antibody 9G10 is present on cell surface of the antibody producing cell and strongly activates engineered T-cells #1138 by CAR cross-linking. Under these test conditions the number of CD30.sup.+CD4.sup.+ T-cells or of CD3.sup.+CD19.sup.+ B-cells in the peripheral blood of treated mice was not altered (FIG. 5).

(72) 3. No Altered Immune Response after LCMV Infection as Test Pathogen

(73) To explore whether the lymphocyte immune response against pathogens is altered in presence of T-cells #1138, the engrafted human immune system in Rag2.sup./31 cy.sup./31 mice was challenged by infection with lympho-choriomeningitis virus (LCMV) at day 7 after adoptive therapy with T-cells # 1138.

(74) This assay is based on the fact that systemic LCMV infection in an immune competent host is controlled by specific CD8.sup.+ and CD4.sup.+ T-cells which become activated, produce an inflammatory infiltrate at the infection site and transiently express CD30 at high levels. Rag2.sup./31 cy.sup./31 mice without transplanted T- and B-cell immune system cannot produce an anti-LCMV T-cell response. Humanized Rag2.sup./31 cy.sup./31 mice with transplanted human immune system are asked whether they produce an inflammatory infiltrate after LCMV infection.

(75) We challenged the immune response against LCMV by local virus application into the foot path. This is a classical infection assay to indicate the anti-virus immune response by swelling at the infection site within a few days.

(76) We here recorded swelling of the foot path at the infection site as it is known for wild-type mice with full immune competence, e.g., balb/c mice. No loss of body weight was recorded in the experimental mouse treated by this route of infection. Data indicate that local LCMV infection is locally controlled in reconstituted Rag2.sup./31 cy.sup./31 mice after therapy with anti-CD30 CAR T-cells #1138. No mouse died during the study.

(77) However, a weight loss of about 30% (in average from 18 g to 12 g at day 10 vs day 27) was observed. Mice which received 9G10 antibody cells to stimulate the anti-CD30 T-cells #1138 controlled LCMV infection with less dramatic weight. For comparison, humanized Rag2.sup./31 cy.sup./31 mice after therapy with anti-CEA T-cells #1175 did not show weight loss.

(78) Data demonstrate that humanized mice with anti-CD30 T-cells #1138 are capable to conduct a cellular immune response upon LCMV infection indicated by foot path swelling in all cases. In mice treated with anti-CD30 T-cells #1138, however, response to LCMV infection may be associated with a moderate cytokine release syndrome due to acute T-cell #1138 activation leading to reduced food uptake and in weight loss. This is in contrast to mice which received the control T-cells with anti-CEA #1175 CAR which does not have a target in those mice and do not become activated.

(79) 4. Serum Pathology

(80) Serum GOT (glutamic oxaloacetic transaminase) was recorded in mice of each experimental group and moreover in one mouse of each group which was systemically infected with LCMV. Serum GOT and GPT (glutamic-pyruvic transaminase) were determined by the Institut fr Klinische Chemie, Uniklinik Kln, by using their SOPs. No significant changes in serum GOT levels were observed in treated mice during the observation period up to 57 days after T-cell therapy.

Conclusions

(81) The toxicity of T-cells #1138 toward healthy autologous CD30.sup.+ lymphocytes was tested in Rag2.sup./31 cy.sup./31 mice fully reconstituted with the human hematopoietic system. T-cells from three donors were engineered with the anti-CD30 CAR #1138, as control with the anti-CEA CAR #1175, and tested for autoimmune reactivity towards the autologous healthy CD30.sup.+ lymphocytes, in particular for the elimination of CD30.sup.+ CD19+ B-cells and CD30.sup.+ CD4+ T-cells. The total observation time for both the test and the control group was 60 days.

(82) No signs of disease were recorded in treated mice. The frequency of CD30.sup.+ CD19+ B-cells and CD30.sup.+ CD4+ T-cells in the peripheral blood was not altered. The lack of signs of autoimmune toxicity was challenged by in vivo stimulation of engineered T-cells #1138 by application of the anti-idiotypic antibody 9G10 which binds to the binding domain of the CAR and induces CAR signalling and T-cell activation. No alteration in the frequency of CD30.sup.+ CD19.sup.+ B-cells and CD30.sup.+ CD4+ T-cells in the peripheral blood was observed.

(83) The lymphocyte immune response against pathogens in humanized mice treated with anti-CD30 T-cells #1138 was not altered as shown by local infection with lymphochoriomeningitis virus (LCMV) at day 7 after transfer of T-cells #1138. Treated mice, however, suffered from a weight loss of about 30% (day 10 vs day 27). Since mice with transplanted T-cells #1175 did not show weight loss after LCMV infection we conclude that the anti-LCMV immune response in mice with T-cells #1138 produced a moderate cytokine release syndrome due to acute activation against CD30.sup.+ target cells leading to less food uptake. No mouse died during infection.

(84) Under the present test conditions adoptive therapy with T-cells #1138 preserved the B- and T-cell counts in peripheral blood and allowed a cellular immune protection against a test pathogen.

Example 3: Specific Expansion of #1138 CAR Modified T-cells

Engineering of T-cells with CAR #1138 and #946

(85) Engraftment of human peripheral T-cells with #1138 and for comparison #946 CAR, see Hombach A, et. Al., Gene Ther. 2010 October;17(10):1206-13. doi: 10.1038/gt.2010.91. Epub 2010 Jun. 17, harbouring a CEA-specific scFv binding domain CEA was assessed by two colour FACS after 12 hrs after transduction. The initial efficiency was 29% for #1138 CAR and 22% for #946 CAR T-cells, respectively.

Monitoring T-cells with CAR #1138 and #946

(86) After transduction cells were cultured in Xvivo15 medium supplemented with 10% FCS and IL-2 (500 U/ml). Medium was replaced once a week, IL-2 was added every 3rd day. A sample of cells was removed at different time points and CD3+ T-cells were analyzed for CAR expression utilizing FITC-conjugated anti-mouse and PE-conjugated anti-human IgG1 Fc antibodies. Data are summarized in FIG. 6.

Conclusions

(87) The number of #1138 CAR T-cells increased substantially during extended cultivation up to 300 h compared with #946 CAR T-cells and resulted in >90% of all T-cells with #1138 CAR compared to 50% T-cells with #946 CAR.

Example 4: Specific Cytolysis of B-cells

(88) As shown in FIG. 7a, B-cells were isolated from PBMC according to standard procedures. In addition, T-cells were isolated from PBMC, grafted with CAR #1138, CFSE-labeled and separated into CAR.sup.+ and CAR.sup. populations. The autologous B-cells were activated for 96 h by sCD40L/IL-4 according to standard procedures, labelled with PKH26 and sorted into CD30.sup.+ and CD30.sup. populations by flow cytometry based cell sorting. Labelled T-cells were co-cultivated (2.510.sup.4/well) for 24 h with B-cells, recovered, stained with 7-AAD and analysed by flow cytometry. For control, target cell lysis of Myla cells representing malignant T-cells was determined by a XTT-based viability assay. As shown in FIG. 7B, there is no significant cytolysis of CD19+ B-cells by CAR+ or CAR T-cells whereas a substantial cytolysis of CD30+ Myla cells occurred when co-incubated with #1138 CAR T-cells. Moreover, there is no substantial difference in cytolysis of CD30+ and CD30 cells of the CD19+ B-cells by CAR #1138 T-cells compared to T-cells without CAR.