DPP3 IN PATIENTS INFECTED WITH CORONAVIRUS
20230213519 · 2023-07-06
Assignee
Inventors
Cpc classification
G01N2800/52
PHYSICS
C07K2317/24
CHEMISTRY; METALLURGY
C07K2317/76
CHEMISTRY; METALLURGY
G01N2800/325
PHYSICS
C07K2317/34
CHEMISTRY; METALLURGY
C07K16/2896
CHEMISTRY; METALLURGY
C07K2317/92
CHEMISTRY; METALLURGY
International classification
Abstract
Subject matter of the present invention is a method for (a) diagnosing or predicting the risk of life-threatening deterioration or an adverse event or (b) diagnosing or prognosing the severity or (c) predicting or monitoring the success of a therapy or intervention or (d) therapy guidance or therapy stratification or (e) patient management in a patient infected with a coronavirus, the method comprising: determining the level of dipeptidyl peptidase 3 (DPP3) in a sample of bodily fluid of said patient, comparing said level of determined DPP3 to a pre-determined threshold, and correlating said level of determined DPP3 with the risk of life-threatening deterioration or an adverse event, or correlating said level of determined DPP3 with the severity, or correlating said level of determined DPP3 with the success of a therapy or intervention, or correlating said level of DPP3 with a certain therapy or intervention, or correlating said level of DPP3 with the management of said patient.
Subject matter of the present invention is an inhibitor of the activity of DPP3 for use in therapy or intervention in a patient infected with a coronavirus.
Claims
1. A method comprising: preparing a sample, wherein said sample comprises bodily fluid from a patient and a capture binder to dipeptidyl peptidase 3 (DDP3) wherein the level of dipeptidyl peptidase 3 (DPP3) in the sample of bodily fluid of said patient is above a pre-determined threshold, and wherein the patient has been determined to be infected with a coronavirus.
2. The method of claim 1, wherein said coronavirus is selected from the group consisting of SARS-CoV-1, SARS-CoV-2, and MERS-CoV.
3. (canceled)
4. (canceled)
5. (canceled)
6. The method of claim 1, wherein said capture-binder is selected from the group consisting of antibody, antibody fragment or non-IgG scaffold.
7. A method for (a) diagnosing or predicting the risk of life-threatening deterioration or an adverse event or (b) diagnosing or prognosing the severity or (c) predicting or monitoring the success of a therapy or intervention or (d) therapy guidance or therapy stratification or (c) patient management in a patient infected with a coronavirus comprising: determining the level of dipeptidyl peptidase 3 (DPP3) in a sample of bodily fluid of said patient, comparing said level of determined DPP3 to a pre-determined threshold, and correlating said level of determined DPP3 with the risk of life-threatening deterioration or an adverse event, or correlating said level of determined DPP3 with the severity, or correlating said level of determined DPP3 with the success of a therapy or intervention, correlating said level of DPP3 with a certain therapy or intervention, or correlating said level of DPP3 with the management of said patient, treating said patient with an inhibitor of DPP3 activity and/or an angiotensin-receptor-agonist and/or a precursor of said angiotensin-receptor-agonist.
8. A method of treatment comprising: treating a patient diagnosed with a coronavirus with an inhibitor of the activity of DPP3 and/or an angiotensin-receptor-agonist and/or a precursor of said angiotensin-receptor-agonist.
9. The method of claim 8 wherein said coronavirus is selected from the group consisting of Sars-CoV-1, Sars-CoV-2, and MERS-CoV.
10. The method of claim 8 wherein said patient has a level of DPP3 in a sample of bodily fluid of said subject that is above a predetermined threshold.
11. The method of claim 8, wherein the inhibitor of the activity of DPP3 is selected from the group consisting of anti-DPP3 antibody, anti-DPP3 antibody fragment, and anti-DPP3 non-Ig scaffold.
12. The method of claim 8, wherein said inhibitor is an anti-DPP3 antibody or anti-DPP3 antibody fragment or anti-DPP3 non-Ig scaffold that binds an epitope of at least 4 to 5 amino acids in length comprised in SEQ ID No. 1.
13. The method of claim 8, wherein said inhibitor is an anti-DPP3 antibody or anti-DPP3 antibody fragment or anti-DPP3 non-Ig scaffold that binds an epitope of at least 4 to 5 amino acids in length comprised in SEQ ID No. 2.
14. The method of claim 6, wherein said antibody is a monoclonal antibody or monoclonal antibody fragment.
15. The method of claim 14, wherein the complementarity determining regions (CDR's) in the heavy chain of said monoclonal antibody or monoclonal antibody fragment comprises the sequences: SEQ ID NO.: 7, SEQ ID NO.: 8 and/or SEQ ID NO.: 9 and the complementarity determining regions (CDR's) in the light chain comprises the sequences: SEQ ID NO.: 10, KVS and/or SEQ ID NO.: 11.
16. The method of claim 15, wherein said monoclonal antibody or antibody fragment is a humanized monoclonal antibody or humanized monoclonal antibody fragment.
17. The method of claim 16, wherein the heavy chain comprises the sequence: SEQ ID NO.: 12 and wherein the light chain comprises the sequence: SEQ ID NO.: 13.
18. The method of claim 8, wherein said Angiotensin-receptor-agonist and/or a precursor thereof is selected and also selected from the group consisting of angiotensin I, angiotensin II, angiotensin III, and angiotensin IV.
Description
FIGURE DESCRIPTION
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[0277] (A) 7-Day survival of patients with sepsis/septic shock in relation to DPP3 plasma concentration (cut-off 68.6 ng/mL); (B) 7-Day survival of patients with cardiogenic shock in relation to DPP3 plasma concentration (cut-off 68.6 ng/mL); (C) 7-day survival of patients with acute myocardial infarction in relation to DPP3 plasma concentration (cut-off 68.6 ng/mL); (D) 3-month survival of patients with dyspnea in relation to DPP3 plasma concentration; (E) 4-week survival of burned patients in relation to DPP3 plasma concentration.
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EXAMPLES
Example 1—Methods for the Measurement of DPP 3 Protein and DPP3 Activity
[0298] Generation of antibodies and determination DPP3 binding ability: Several murine antibodies were produced and screened by their ability of binding human DPP3 in a specific binding assay (see Table 2).
[0299] Peptides/Conjugates for Immunization:
[0300] DPP3 peptides for immunization were synthesized, see Table 2, (JPT Technologies, Berlin, Germany) with an additional N-terminal cystein (if no cystein is present within the selected DPP3-sequence) residue for conjugation of the peptides to Bovine Serum Albumin (BSA). The peptides were covalently linked to BSA by using Sulfolink-coupling gel (Perbio-science, Bonn, Germany). The coupling procedure was performed according to the manual of Perbio. Recombinant GST-hDPP3 was produced by USBio (United States Biological, Salem, Mass., USA).
[0301] Immunization of Mice, Immune Cell Fusion and Screening:
[0302] Balb/c mice were intraperitoneally (i.p.) injected with 84 μg GST-hDPP3 or 100 μg DPP3-peptide-BSA-conjugates at day 0 (emulsified in TiterMax Gold Adjuvant), 84 μg or 100 μg at day 14 (emulsified in complete Freund's adjuvant) and 42 μg or 50 μg at day 21 and 28 (in incomplete Freund's adjuvant). At day 49 the animal received an intravenous (i.v.) injection of 42 μg GST-hDPP3 or 50 μg DPP3-peptide-BSA-conjugates dissolved in saline. Three days later the mice were sacrificed and the immune cell fusion was performed.
[0303] Splenocytes from the immunized mice and cells of the myeloma cell line SP2/0 were fused with 1 ml 50% polyethylene glycol for 30 s at 37° C. After washing, the cells were seeded in 96-well cell culture plates. Hybrid clones were selected by growing in HAT medium [RPMI 1640 culture medium supplemented with 20% fetal calf serum and HAT-Supplement]. After one week, the HAT medium was replaced with HT Medium for three passages followed by returning to the normal cell culture medium.
[0304] The cell culture supernatants were primarily screened for recombinant DPP3 binding IgG antibodies two weeks after fusion. Therefore, recombinant GST-tagged hDPP3 (USBiologicals, Salem, USA) was immobilized in 96-well plates (100 ng/well) and incubated with 50 μl cell culture supernatant per well for 2 hours at room temperature. After washing of the plate, 50 μl/well POD-rabbit anti mouse IgG was added and incubated for 1 h at RT. After a next washing step, 50 μl of a chromogen solution (3.7 mM o-phenylen-diamine in citrate/hydrogen phosphate buffer, 0.012% H.sub.2O.sub.2) were added to each well, incubated for 15 minutes at RT and the chromogenic reaction stopped by the addition of 50 μl 4N sulfuric acid. Absorption was detected at 490 mm.
[0305] The positive tested microcultures were transferred into 24-well plates for propagation. After retesting the selected cultures were cloned and re-cloned using the limiting-dilution technique and the isotypes were determined.
[0306] Mouse Monoclonal Antibody Production
[0307] Antibodies raised against GST-tagged human DPP3 or DPP3-peptides were produced via standard antibody production methods (Marx et al. 1997) and purified via Protein A. The antibody purities were ≥90% based on SDS gel electrophoresis analysis.
[0308] Characterization of Antibodies—Binding to hDPP3 and/or Immunization Peptide
[0309] To analyze the capability of DPP3/immunization peptide binding by the different antibodies and antibody clones a binding assay was performed:
[0310] a) Solid Phase
[0311] Recombinant GST-tagged hDPP3 (SEQ ID NO. 1) or a DPP3 peptide (immunization peptide, SEQ ID NO. 2) was immobilized onto a high binding microtiter plate surface (96-Well polystyrene microplates, Greiner Bio-One international AG, Austria, 1 μg/well in coupling buffer [50 mM Tris, 100 mM NaCl, pH7,8], 1 h at RT). After blocking with 5% bovine serum albumin, the microplates were vacuum dried.
[0312] b) Labelling Procedure (Tracer)
[0313] 100 μg (100 μl) of the different antiDPP3 antibodies (detection antibody, 1 mg/ml in PBS, pH 7.4) were mixed with 10 μl acridinium NHS-ester (1 mg/ml in acetonitrile, InVent GmbH, Germany; EP 0 353 971) and incubated for 30 min at room temperature. Labelled antiDPP3 antibody was purified by gel-filtration HPLC on Shodex Protein 5 μm KW-803 (Showa Denko, Japan). The purified labeled antibody was diluted in assay buffer (50 mmol/1 potassium phosphate, 100 mmol/1 NaCl, 10 mmol/1 Nae-EDTA, 5 g/l bovine serum albumin, 1 g/l murine IgG, 1 g/l bovine IgG, 50 μmol/l amastatin, 100 μmol/l leupeptin, pH 7.4). The final concentration was approx. 5-7*10.sup.6 relative light units (RLU) of labelled compound (approx. 20 ng labeled antibody) per 200 acridinium ester chemiluminescence was measured by using a Centro LB 960 luminometer (Berthold Technologies GmbH & Co. KG).
[0314] c) hDPP3 Binding Assay
[0315] The plates were filled with 200 μl of labelled and diluted detection antibody (tracer) and incubated for 2-4 h at 2-8° C. Unbound tracer was removed by washing 4 times with 350 μl washing solution (20 mM PBS, pH 7.4, 0.1% Triton X-100). Well-bound chemiluminescence was measured by using the Centro LB 960 luminometer (Berthold Technologies GmbH & Co. KG).
[0316] Characterization of Antibodies—hDPP3-Inhibition Analysis
[0317] To analyze the capability of DPP3 inhibition by the different antibodies and antibody clones a DPP3 activity assay with known procedure (Jones et al., 1982) was performed. Recombinant GST-tagged hDPP3 was diluted in assay buffer (25 ng/ml GST-DPP3 in 50 mM Tris-HCl, pH7.5 and 100 μM ZnCl.sub.2) and 200 μl of this solution incubated with 10 μg of the respective antibody at room temperature. After 1 hour of pre-incubation, fluorogenic substrate Arg-Arg-βNA (20 μl, 2 mM) was added to the solution and the generation of free βNA over time was monitored using the Twinkle LB 970 microplate fluorometer (Berthold Technologies GmbH & Co. KG) at 37° C. Fluorescence of βNA is detected by exciting at 340 nm and measuring emission at 410 nm. Slopes (in RFU/min) of increasing fluorescence of the different samples are calculated. The slope of GST-hDPP3 with buffer control is appointed as 100% activity. The inhibitory ability of a possible capture-binder is defined as the decrease of GST-hDPP3 activity by incubation with said capture-binder in percent.
[0318] The following table represents a selection of obtained antibodies and their binding rate in Relative Light Units (RLU) as well as their relative inhibitory ability (%; table 1). The monoclonal antibodies raised against the below depicted DPP3 regions, were selected by their ability to bind recombinant DPP3 and/or immunization peptide, as well as by their inhibitory potential.
[0319] All antibodies raised against the GST-tagged, full length form of recombinant hDPP3 show a strong binding to immobilized GST-tagged hDPP3. Antibodies raised against the SEQ ID No.: 2 peptide bind to GST-hDPP3 as well. The SEQ ID No.: 2 antibodies also strongly bind to the immunization peptide.
TABLE-US-00010 TABLE 2 list of antibodies raised against full-length or sequences of hDPP3 and their ability to bind hDPP3 (SEQ ID NO.: 1) or immunization peptide (SEQ ID NO.: 2) in RLU, as well as the maximum inhibition of recombinant GST-hDPP3. immunization hDPP3 peptide Max. Sequence hDPP3 binding binding inhibition number Antigen/Immunogen region Clone [RLU] [RLU] of hDPP3 SEQ ID GST tagged 1- 2552 3.053.621 0 65% NO.: 1 recombinant 737 2553 3.777.985 0 35% FL-hDPP3 2554 1.733.815 0 30% 2555 3.805.363 0 25% SEQ ID CETVINPETGEQIQSWYR 474- 1963 141.822 2.163.038 60% NO.: 2 SGE 493 1964 100.802 2.041.928 60% 1965 99.493 1.986.794 70% 1966 118.097 1.990.702 65% 1967 113.736 1.909.954 70% 1968 105.696 2.017.731 65% 1969 82.558 2.224.025 70%
[0320] The development of a luminescence immunoassay for the quantification of DPP3 protein concentrations (DPP3-LIA) as well as an enzyme capture activity assay for the quantification of DPP3 activity (DPP3-ECA) have been described recently (Rehfeld et al. 2019. JALM 3(6): 943-953), which is incorporated here in its entirety by reference.
Example 2—DPP3 for Prognosis of Short-Term Mortality
[0321] DPP3 concentration in plasma of a variety of diseased patients was determined using a hDPP3 immunoassay (Rehfeld et al. 2019. JALM 3(6): 943-953) and related to the short term-mortality of the patients.
[0322] Study Cohort—Sepsis and Septic Shock
[0323] Plasma samples form 574 patients from the Adrenomedullin and Outcome in Severe Sepsis and Septic Shock (AdrenOSS-1) study were screened for DPP3. AdrenOSS-1 is a prospective, observational, multinational study including 583 patients admitted to the intensive care unit with sepsis or septic shock (Hollinger et al., 2018). 292 patients were diagnosed with septic shock.
[0324] Study Cohort—Cardiogenic Shock
[0325] Plasma samples from 108 patients that were diagnosed with cardiogenic shock were screened for DPP3. Blood was drawn within 6 h from detection of cardiogenic shock. Mortality was followed for 7 days.
[0326] Study Cohort—Acute Coronary Syndrome
[0327] Plasma samples from 720 patients with acute coronary syndrome were screened for DPP3. Blood was drawn 24 hours after the onset of ChestPain. Mortality was followed for 7 days.
[0328] Study Cohort—Dyspnea:
[0329] Plasma samples from 1440 patients presenting with dyspnea (shortness of breath) were collected immediately to their entry to the emergency department of Sickle University Hospital. Patients with dyspnea may suffer from acute coronary syndrome or congestive heart failure, beside others, and have a high risk for organ failure and short-term mortality. Mortality was followed for 3 months after presentation to the emergency department.
[0330] Study Cohort—Burned Patients:
[0331] Plasma samples from 107 patients with severe burns (more than 15% of total body surface area) were screened for DPP3. Blood was drawn at admission to the hospital. Mortality was followed for 4 weeks.
[0332] Hdpp3 Immunoassay:
[0333] An immune-assay (LIA) or an activity assays (ECA) detecting the amount of human DPP3 (LIA) or the activity of human DPP3 (ECA), respectively, was used for determining the DPP3 level in patient plasma. Antibody immobilization, labelling and incubation were performed as described in Rehfeld et al. (Rehfeld et al. 2019. JALM 3(6): 943-953).
[0334] Results
[0335] Short-term patients' survival in Sepsis/Septic Shock was related to the DPP3 plasma concentration at admission. Patients with DPP3 plasma concentration above 68.6 ng/mL (3. Quartile) had an increased mortality risk compared to patients with DPP3 plasma concentrations below this threshold (
[0336] In addition, 28 day-survival of patients with acute coronary syndrome in relation to DPP3 is also increased when DPP3 is high and the respective cut-off of 68.6 ng/mL is applied (
[0337] Applying this cut-off of 68.6 ng/mL to patients that suffer from Dyspnea, a significant increased mortality risk for patients with high DPP3 is detected within a follow-up of 3 months (
[0338] Furthermore, there was an increased risk for 4-week mortality in severely burned patients that have a high DPP3 concentration above the respective cut-off off 68.6 ng/mL (
Example 3—Purification of Human Native DPP3
[0339] Human erythrocyte lysate was applied on a total of 100 ml of Sepahrose 4B resin (Sigma-Aldrich) and the flow through was collected. The resin was washed with a total of 370 mL PBS buffer, pH 7.4 and the wash fraction was combined with the collected flow through, resulting in a total volume of 2370 mL.
[0340] For the immuno-affinity purification step, 110 mg of monoclonal anti-hDPP3 mAb AK2552 were coupled to 25.5 mL of UltraLink Hydrazide Resin (Thermo Fisher Scientific) according to the manufacturer's protocol (GlycoLink Immobilization Kit, Thermo Fisher Scientific). The coupling efficiency was 98%, determined by quantification of uncoupled antibody via Bradford-technique. The resin-antibody conjugate was equilibrated with 10 bed volumes of wash-binding buffer (PBS, 0.1% TritonX-100, pH 7.4), combined with 2370 mL of cleared red blood cell lysate and incubated at 4° C. under continuous stirring for 2 h. Consequently, 100 mL of the incubation mixture was spread on ten 15 mL polypropylene columns and the flow-through was collected by centrifugation at 1000×g for 30 seconds. This step was repeated several times resulting in 2.5 mL of DPP3-loaded resin per column Each column was washed 5 times with 10 mL of wash-binding buffer using the gravity-glow approach. DPP3 was eluted by placing each column in 15-mL falcon tube containing 2 mL of neutralization buffer (1M Tris-HCl, pH 8.0), followed by addition of 10 mL of elution buffer (100 mM Glycine-HCl, 0.1% TritonX-100, pH 3.5) per column and immediate centrifugation for 30 seconds at 1000×g. The elution step was repeated 3 times in total resulting in 360 mL of combined eluates. The pH of the neutralized eluates was 8.0.
[0341] The combined eluates were loaded on a 5 mL HiTrap Q-sephare HP column (GE Healthcare) equilibrated with IEX-buffer A1 (100 mM Glycine, 150 mM Tris, pH 8.0) using the sample pump of the Äkta Start system (GE Healthcare). After sample loading, the column was washed with five column volumes of IEX Buffer A2 (12 mM NaH.sub.2PO.sub.4, pH 7.4) to remove unbound protein. Elution of DPP3 was achieved by applying a sodium chloride gradient over 10 column volumes (50 mL) in a range of 0-1 M NaCl using IEX-buffer B (12 mM NaH.sub.2PO.sub.4,1 M NaCl, pH 7.4). The eluates were collected in 2 mL fractions. Buffers used for ion exchange chromatography were sterile filtered using a 0.22 μM bottle-top filter.
[0342] A purification table with the respective yields and activities of each purification step is given in table 3.
TABLE-US-00011 TABLE 3 Purification of DPP3 from human erythrocytes DPP3 Total Specific amount Total activity in activity in % protein μmol/min Yield.sup.d) in Purification Step (LIA).sup.a) in mg.sup.b) (ECA).sup.c) in % U/mg.sup.e) factor.sup.f) Lysate 100 204160 55 100 0.00027 — IAP 80.6 71.2 46.1 84 0.65 2407 IEX 75 6.6 38.7 70 5.9 21852 .sup.a)Relative DPP3 amount was determined in all fractions using the DPP3-LIA assay. Amount of DPP3 in starting material was set to 100% and remaining DPP3 amount in purification fractions was correlated to the starting material. .sup.b)Total protein amount was determined using the method of Lowry modified by Peterson (Peterson 1977. Analytical Biochemistry 356:346-356). .sup.c)Total Arg.sub.2-βNA hydrolyzing activity in μmol of substrate converted per minute was determined using the DPP3-ECA, calibrated via β-naphtylamine (0.05-100 μM). .sup.d)Purification yield was calculated form total Arg.sub.2-βNA hydrolyzing activity. Arg.sub.2-βNA hydrolyzing activity in starting material was set to 100%. .sup.e)Specific activity is defined as μmol of substrate converted per minute and mg of total protein. .sup.f)The purification factor is the quotient of specific activities after and before each purification step.
Example 4—Effect of Native DPP3 in an Animal Model
[0343] The effect of native hDPP3 injection in healthy mice was studied by monitoring the shortening fraction and renal resistive index.
[0344] Wild type Black 6 mice (8-12 weeks, group size refer to table 4) were acclimated during 2 weeks and a baseline echocardiography was done. The mice were randomly allocated to one of the two groups and, subsequently, native DPP3 protein or PBS were injected intravenously via a retro-orbital injection with a dose of 600 μg/kg for DPP3 protein.
[0345] After DPP3 or PBS injection, cardiac function was assessed by echocardiography (Gao et al. 2011) and renal function assessed by renal resistive index (Lubas et al., 2014, Dewitte et al, 2012) at 15, 60 and 120 minutes (
TABLE-US-00012 TABLE 4 list of experiment groups Number Group of Animals Treatment WT + PBS 3 PBS WT + DPP3 4 Native DPP3
[0346] Results
[0347] The mice treated with native DPP3 protein show significantly reduced shortening fraction compared to the control group injected with PBS (
Example 5—Development of Procizumab
[0348] Antibodies raised against SEQ ID No.: 2 were characterized in more detail (epitope mapping, binding affinities, specificity, inhibitory potential). Here the results for clone 1967 of SEQ ID No.: 2 (AK1967; “Procizumab”) are shown as an example.
[0349] Determination of AK1967 Epitope on DPP3:
[0350] For epitope mapping of AK1967 a number of N- or C-terminally biotinylated peptides were synthesized (peptides & elephants GmbH, Hennigsdorf, Germany). These peptides include the sequence of the full immunization peptide (SEQ ID No. 2) or fragments thereof, with stepwise removal of one amino acid from either C- or N-terminus (see table 6 for a complete list of peptides).
[0351] High binding 96 well plates were coated with 2 μg Avidin per well (Greiner Bio-One international AG, Austria) in coupling buffer (500 mM Tris-HCl, pH 7.8, 100 mM NaCl).
[0352] Afterwards plates were washed and filled with specific solutions of biotinylated peptides (10 ng/well; buffer—1×PBS with 0.5% BSA)
[0353] Anti-DPP3 antibody AK1967 was labelled with a chemiluminescence label according to Example 1.
[0354] The plates were filled with 200 μl of labelled and diluted detection antibody (tracer) and incubated for 4 h at room temperature. Unbound tracer was removed by washing 4 times with 350 μl washing solution (20 mM PBS, pH 7.4, 0.1% Triton X-100). Well-bound chemiluminescence was measured by using the Centro LB 960 luminometer (Berthold Technologies GmbH & Co. KG). Binding of AK1967 to the respective peptides is determined by evaluation of the relative light units (RLU). Any peptide that shows a significantly higher RLU signal than the unspecific binding of AK1967 is defined as AK1967 binder. The combinatorial analysis of binding and non-binding peptides reveals the specific DPP3 epitope of AK1967.
[0355] Determination of Binding Affinities Using Octet:
[0356] The experiment was performed using Octet Red96 (ForteBio). AK1967 was captured on kinetic grade anti-humanFc (AHC) biosensors. The loaded biosensors were then dipped into a dilution series of recombinant GST-tagged human DPP3 (100, 33.3, 11.1, 3.7 nM). Association was observed for 120 seconds followed by 180 seconds of dissociation. The buffers used for the experiment are depicted in table 5. Kinetic analysis was performed using a 1:1 binding model and global fitting.
TABLE-US-00013 TABLE 5 Buffers used for Octet measurements Buffer Composition Assay Buffer PBS with 0.1% BSA, 0.02% Tween-21 Regeneration Buffer 10 mM Glycine buffer (pH 1.7) Neutralization Buffer PBS with 0.1% BSA, 0.02% Tween-21
[0357] Western Blot Analysis of Binding Specificity of AK1967:
[0358] Blood cells from human EDTA-blood were washed (3× in PBS), diluted in PBS and lysed by repeated freeze-thaw-cycles. The blood cell lysate had a total protein concentration of 250 μg/ml, and a DPP3 concentration of 10 μg/ml. Dilutions of blood cell lysate (1:40, 1:80, 1:160 and 1:320) and of purified recombinant human His-DPP3 (31.25-500 ng/ml) were subjected to SDS-PAGE and Western Blot. The blots were incubated in 1.) blocking buffer (1×PBS-T with 5% skim milk powder), 2.) primary antibody solution (AK1967 1:2.000 in blocking buffer) and 3.) HRP labelled secondary antibody (goat anti mouse IgG, 1:1.000 in blocking buffer). Bound secondary antibody was detected using the Amersham ECL Western Blotting Detection Reagent and the Amersham Imager 600 UV (both from GE Healthcare).
[0359] DPP3 Inhibition Assay:
[0360] To analyze the capability of DPP3 inhibition by AK1967 a DPP3 activity assay with known procedure (Jones et al., 1982) was performed as described in example 1. The inhibitory ability AK1967 is defined as the decrease of GST-hDPP3 activity by incubation with said antibody in percent. The resulting lowered DPP3 activities are shown in an inhibition curve in
[0361] Epitope Mapping:
[0362] The analysis of peptides that AK1967 binds to and does not bind to revealed the DPP3 sequence INPETG (SEQ ID No.: 3) as necessary epitope for AK1967 binding (see table 6).
[0363] Binding Affinity:
[0364] AK1967 binds with an affinity of 2.2*10.sup.−9 M to recombinant GST-hDPP3 (kinetic curves see
TABLE-US-00014 TABLE 6 Peptides used for Epitope mapping of AK1967 (Table discloses SEQ ID NOS 14-30, respectively, in order of appearance) peptide AK1967 ID peptide sequence binding #1 #2 #3 #4 #5 #6
[0365] Specificity and Inhibitory Potential:
[0366] The only protein detected with AK1967 as primary antibody in lysate of blood cells was DPP3 at 80 kDa (
[0367] AK1967 inhibits 15 ng/ml DPP3 in a specific DPP3 activity assay with an IC50 of about 15 ng/ml (
[0368] Chimerization/Humanization:
[0369] The monoclonal antibody AK1967 (“Procizumab”), with the ability of inhibiting DPP3 activity by 70%, was chosen as possible therapeutic antibody and was also used as template for chimerization and humanization.
[0370] Humanization of Murine Antibodies May be Conducted According to the Following Procedure:
[0371] For humanization of an antibody of murine origin the antibody sequence is analyzed for the structural interaction of framework regions (FR) with the complementary determining regions (CDR) and the antigen. Based on structural modelling an appropriate FR of human origin is selected and the murine CDR sequences are transplanted into the human FR. Variations in the amino acid sequence of the CDRs or FRs may be introduced to regain structural interactions, which were abolished by the species switch for the FR sequences. This recovery of structural interactions may be achieved by random approach using phage display libraries or via directed approach guided by molecular modeling (Almagro and Fransson, 2008. Humanization of antibodies. Front Biosci. 13:1619-33).
[0372] With the above context, the variable region can be connected to any subclass of constant regions (IgG, IgM, IgE. IgA), or only scaffolds, Fab fragments, Fv, Fab and F(ab)2. In example 6 and 7 below, the murine antibody variant with an IgG2a backbone was used. For chimerization and humanization a human IgG1K backbone was used.
[0373] For epitope binding only the Complementarity Determining Regions (CDRs) are of importance. The CDRs for the heavy chain and the light chain of the murine anti-DPP3 antibody (AK1967; “Procizumab”) are shown in SEQ ID No. 7, SEQ ID No. 8 and SEQ ID No. 9 for the heavy chain and SEQ ID No. 10, sequence KVS and SEQ ID No. 11 for the light chain, respectively.
[0374] Sequencing of the anti-DPP3 antibody (AK1967; “Procizumab”) revealed an antibody heavy chain variable region (H chain) according to SEQ ID No.: 12 and an antibody light chain variable region (L chain) according to SEQ ID No.: 13.
Example 6—Effect of Procizumab in Sepsis-Induced Heart Failure
[0375] In this experiment, the effect of Procizumab injection in sepsis-induced heart failure rats (Rittirsch et al. 2009) was studied by monitoring the shortening fraction.
[0376] CLP Model of Septic Shock:
[0377] Male Wistar rats (2-3 months, 300 to 400 g, group size refers to table 7) from the Centre d′élevage Janvier (France) were allocated randomly to one of three groups. All the animals were anesthetized using ketamine hydrochloride (90 mg/kg) and xylazine (9 mg/kg) intraperitoneally (i.p.). For induction of polymicrobial sepsis, cecal ligation and puncture (CLP) was performed using Rittirsch's protocol with minor modification. A ventral midline incision (1.5 cm) was made to allow exteriorization of the cecum. The cecum is then ligated just below the ileocecal valve and punctured once with an 18-gauge needle. The abdominal cavity is then closed in two layers, followed by fluid resuscitation (3 ml/100 g body of weight of saline injected subcutaneously) and returning the animal to its cage Sham animals were subjected to surgery, without getting their cecum punctured. CLP animals were randomized between placebo and therapeutic antibody.
[0378] Study Design:
[0379] The study flow is depicted in
[0380] At t=0 (baseline) all CLP animals are in septic shock and developed a decrease in heart function (low blood pressure, low shortening fraction). At this time point Procizumab or vehicle (PBS) were injected (i.v.) and saline infusion was started. There were 1 control group and 2 CLP groups which are summarized in the table below (table 7). At the end of the experiment, the animals were euthanized, and organs harvested for subsequent analysis.
TABLE-US-00015 TABLE 7 list of experimental groups Number Group of Animals CLP Treatment Sham 7 No PBS CLP-PBS 6 Yes PBS CLP-PCZ 4 Yes PCZ
[0381] Invasive Blood Pressure:
[0382] Hemodynamic variables were obtained using the AcqKnowledge system (BIOPAC Systems, Inc., USA). It provides a fully automated blood pressure analysis system. The catheter is connected to the BIOPAC system through a pressure sensor.
[0383] For the procedure, rats were anesthetized (ketamine and xylazine). Animals were moved to the heating pad for the desired body temperature to 37-37.5° C. The temperature feedback probe was inserted into the rectum. The rats were placed on the operating table in a supine position. The trachea was opened and a catheter (16G) was inserted for an external ventilator without to damage carotid arteries and vagus nerves. The arterial catheter was inserted into the right carotid artery. The carotid artery is separate from vagus before ligation.
[0384] A central venous catheter was inserted through the left jugular vein allowing administration of PCZ or PBS.
[0385] Following surgery, the animals were allowed to rest for the stable condition prior to hemodynamic measurements. Then baseline blood pressure (BP) were recorded. During the data collection, saline infusion via arterial line was stopped.
[0386] Echocardiography:
[0387] Animals were anesthetized using ketamine hydrochloride. Chests were shaved and rats were placed in decubitus position.
[0388] For transthoracic echocardiographic (TTE) examination a commercial GE Healthcare Vivid 7 Ultra-sound System equipped with a high frequency (14-MHz) linear probe and 10-MHz cardiac probe was used. All examinations were recorded digitally and stored for subsequent off-line analysis.
[0389] Grey scale images were recorded at a depth of 2 cm. Two-dimensional examinations were initiated in a parasternal long axis view to measure the aortic annulus diameter and the pulmonary artery diameter. M-mode was also employed to measure left ventricular (LV) dimensions and assess fractional shortening (FS %). LVFS was calculated as LV end-diastolic diameter—LV end-systolic diameter/LV end-diastolic diameter and expressed in %. The time of end-diastole was therefore defined at the maximal diameter of the LV. Accordingly, end-systole was defined as the minimal diameter in the same heart cycle. All parameters were measured manually. Three heart cycles were averaged for each measurement.
[0390] From the same parasternal long axis view, pulmonary artery flow was recorded using pulsed wave Doppler. Velocity time integral of pulmonary artery outflow was measured.
[0391] From an apical five-chamber view, mitral flow was recorded using pulsed Doppler at the level of the tip of the mitral valves.
[0392] Results:
[0393] The sepsis-induced heart failure rats treated with PBS (CLP+PBS) show reduced shortening fraction compared to the sham animals (
Example 7—Effect of Procizumab on Heart and Kidney Function
[0394] The effect of Procizumab in isoproterenol-induced heart failure in mice was studied by monitoring the shortening fraction and renal resistive index.
[0395] Isoproterenol-Induced Cardiac Stress in Mice:
[0396] Acute heart failure was induced in male mice at 3 months of age by two daily subcutaneous injections of 300 mg/kg of Isoproterenol, a non-selective β-adrenergic agonist (DL-Isoproterenol hydrochloride, Sigma Chemical Co) (ISO) for two days (Vergaro et al, 2016). The ISO dilution was performed in NaCl 0.9%. Isoproterenol-treated mice were randomly assigned to two groups (Table 8) and PBS or Procizumab (10 mg/kg) were injected intravenously after baseline echocardiography (Gao et al., 2011) and renal resistive index measurements (Lubas et al., 2014, Dewitte et al, 2012) were performed at day 3 (
[0397] Cardiac function was assessed by echocardiography (Gao et al., 2011) and by the renal resistive index (Lubas et al., 2014, Dewitte et al, 2012) at 1 hour, 6 hours and 24 hours (
TABLE-US-00016 TABLE 8 list of experimental groups Number Group of Animals Treatment Sham + PBS 27 PBS HF + PBS 15 PBS HF + PCZ 20 PCZ
[0398] Results:
[0399] Application of Procizumab to isoproterenol-induced heart failure mice restores heart function within the first hour after administration (
Example 8—Effect of Valsartan
[0400] The effect of an antagonist for the type I angiotensin II receptor (ATR1), Valsartan, in healthy mice injected with DPP3 was studied by monitoring the shortening fraction.
[0401] In this experiment, healthy Black 6 mice (8-12 weeks, group size refer to table 9) consumed water with 50 mg/kg Valsartan per day or just water (Table 9) for a period of two weeks. Subsequently, both groups received an intravenous injection of native DPP3 (600 μg/kg) and the shortening fraction was assessed according to Gao et al., 2011 at 15, 60 and 120 minutes (
TABLE-US-00017 TABLE 9 list of experiment groups Number Group of Animals Treatment WT + DPP3 4 Water + PBS/DPP3 injection Val + DPP3 3 Water + Valsartan/DPP3 injection
[0402] Results:
[0403] DPP3 injection to healthy mice lead to a significant decrease in the shortening fraction (
[0404] The animals that were treated with Valsartan for two weeks have been adapted to blocking of the type I angiotensin II receptor, to the subsequent inhibited angiotensin II-mediated signaling and the inhibited AngII-mediated activity of the heart function. Apparently, under Valsartan treatment, the organism switched to other ways for activating cardiac function independent of type I angiotensin II receptor signaling, as this angiotensin signaling system has been inhibited by Valsartan.
[0405] When DPP3 cleaves Ang II and thus inhibits the angiotensin II-mediated activity of the heart function, those animals that are adapted to a down-regulated angiotensin-system (Valsartan treated animals) showed no signs of heart dysfunction as assessed by the shortening fraction. In contrast thereto, animals that were not treated with the angiotensin II receptor antagonist Valsartan and were not adapted to an inhibited Ang II-mediated signaling, showed a significant decrease in the shortening fraction in response to DPP3 injection and subsequent cleavage and inactivation of AngII
[0406] This experiment clearly shows the relationship between DPP3 and angiotensin II meaning that the DPP3-induced heart dysfunction is angiotensin II-mediated.
Example 9—DPP3 and Organ Dysfunction in Sepsis
[0407] The same study as described in Example 2 (AdrenOSS-1) was used to assess the association between circulating DPP3 (cDPP3), organ (e.g. cardiovascular and renal dysfunction) in patients admitted for sepsis and septic shock. The AdrenOSS-1 is a European prospective, observational, multinational study (ClinicalTrials.gov NCT02393781) including 583 patients admitted to the ICU with sepsis or septic shock. The primary outcome (as described in example 2) was 28-day mortality. Secondary outcomes included organ failure defined by SOFA score, organ support with focus on vasopressor use and need for renal replacement therapy. Blood for the central laboratory was sampled within 24 hours after ICU admission and on day 2.
[0408] For the quantification of DPP3 protein concentrations (DPP3-LIA) an assay as recently described was used (Rehfeld et al. 2019. JALM 3(6): 943-953).
[0409] Median cDPP3 measured at admission in all AdrenOSS-1 patients was 45.1 ng/mL (inter quartile range 27.5-68.6). High DPP3 levels measured at admission were associated with worse metabolic parameters, renal and cardiac function and SOFA score: patients with DPP3 levels below the median had a median SOFA score (points) of 6 (IQR 4-9) compared to a median SOFA score of 8 (IQR 5-11) for patients with DPP3 levels above the median of 45.1 ng/mL (
[0410] Whatever levels of cDPP3 at admission, high concentrations of cDPP3 levels 24 hours later were associated with worst SOFA scores whether global
[0411] In summary these data showed that high levels of cDPP3 were associated with survival and the extent of organ dysfunction in a large international cohort septic or septic shock patients. The study found marked association between cDPP3<45.1 ng/ml at admission and short-term survival as well as the prognostic cut-off value of 45.1 pg/ml in both sepsis and septic shock. Concerning organ dysfunction, there was a positive relationship between cDPP3 and SOFA score at ICU admission. More importantly, the relationship between cPDPP3 levels and extent of organ dysfunction, seen at ICU admission, was also true during the recovery phase. Indeed, patients with high cDPP3 levels at admission who showed a decline towards normal cDPP3 values at day 2 were more likely to recover all organ function including cardiovascular, kidney, lung, liver.
Example 10—DPP3 in Patients Infected with Coronavirus (SARS-CoV-2)
[0412] Plasma samples from 12 patients that were diagnosed of being infected with coronavirus (SARS-CoV-2) were screened for DPP3 and other biomarkers. An immunoassay (LIA) or an activity assays (ECA) detecting the amount of human DPP3 (LIA) or the activity of human DPP3 (ECA), respectively, was used for determining the DPP3 level in patient plasma as described recently (Rehfeld et al. 2019. JALM 3(6): 943-953).
[0413] Bio-ADM levels were measured using an immunoassay as described in Weber et al. 2017 ((Weber et al. 2017. JALM 2(2): 222-233).
[0414] The respective DPP3 and bio-ADM concentrations in individual samples are summarized in table 10.
TABLE-US-00018 TABLE 10 DPP3 and bio-ADM levels in samples from patients infected with coronavirus (SARS-CoV-2) Patient DPP3 bio-ADM No. (ng/ml) (pg/ml) 1 56 133 2 30 45 3 70 214 4 150 85 5 290 437 6 87 66 7 975 79 8 333 174 9 216 35 10 539 199 11 27 53 12 162 401 Median 156.0 109.0 mean 244.6 160.1
[0415] DPP3 concentrations ranged between 27 and 975 ng/ml with a median (IQR) of 156 (59.5-322.3) ng/ml. Bio-ADM concentrations ranged between 35 and 437 pg/ml with a median (IQR) of 109 (56-210) pg/ml. DPP3 concentrations are significantly elevated compared to healthy subjects. Samples from 5,400 normal (healthy) subjects (swedish single-center prospective population-based Study (MPP-RES)) have been measured: median (interquartile range) plasma DPP3 was 14.5 ng/ml (11.3 ng/ml-19 ng/ml). Median plasma bio-ADM (mature ADM-NH.sub.2) in samples from (healthy) subjects was 24.7 pg/ml, the lowest value 11 pg/ml and the 99.sup.th percentile 43 pg/ml (Marino et al. 2014. Critical Care 18: R34).
Example 11—DPP3 in Patients with COVID-19 for Prognosis, Therapy Stratification and Follow-Up
[0416] Cohort Description:
[0417] 21 patients with positive SARS-CoV-2 PCR results and ICU admission were included in this study. Patient characteristics included median age of 63, 76% males, median body mass index (BMI) of 28.6 and admission sequential organ failure assessment (SOFA) score of 5. The exclusion criteria were age<18 years old and pregnancy. The analysis was carried out using real time reverse transcription PCR (RT-PCR). Treatment of patients followed the standards of care in our ICU, including mechanical ventilation, veno-venous ECMO and RRT if needed.
[0418] Blood was sampled on the day of admission and on a daily basis until day 7 for analysis of DPP3 and standard laboratory parameters. DPP3 was measured in EDTA plasma with a one-step luminescence sandwich immunoassay (LIA) as described recently (Rehfeld et al. 2019. JALM 3(6): 943-953).
[0419] Results:
[0420] a) DPP3 at Baseline and Serial Measurements are Associated with Disease Severity
[0421] DPP3 measured at admission to the ICU was associated with worsening renal function during ICU stay as defined by the KDIGO criteria, with 0-1 stages indicating no renal function impairment to slight impairment and low risk and 2-3 stages indicating kidney injury and renal failure and DPP3 values in stages 2-3 were significantly higher compared to those in stage 0-1 (
[0422] Since COVID-19 positive patients tend to remain in the ICU for an average of 21 days, measurement of DPP3 levels during ICU stay (day 3 and day 7) were also associated with a low PaO2/FiO2 ratio (<150) and, therefore, with severe acute respiratory distress syndrome (ARDS) (FALSE=P/F ratio>150; TRUE=P/F ratio<150).
[0423] Moreover, high DPP3 values measured on day 3 (
[0424] b) DPP3 at Baseline and Serial Measurements are Associated with Need of Organ Support Therapies
[0425] High DPP3 values at admission and during ICU stay were significantly associated with need of organ support therapies, in particular vasopressor therapy (day 3;
TABLE-US-00019 SEQUENCES SEQ ID No. 1-hDPP3 aa 1-737 MADTQYILPNDIGVSSLDCREAFRLLSPTERLYAYHLSRAAWYGGLAVLLQTSPEAP YIYALLSRLFRAQDPDQLRQHALAEGLTEEEYQAFLVYAAGVYSNMGNYKSFGDTK FVPNLPKEKLERVILGSEAAQQHPEEVRGLWQTCGELMFSLEPRLRHLGLGKEGITTY FSGNCTMEDAKLAQDFLDSQNLSAYNTRLFKEVDGEGKPYYEVRLASVLGSEPSLDS EVTSKLKSYEFRGSPFQVTRGDYAPILQKVVEQLEKAKAYAANSHQGQMLAQYIESF TQGSIEAHKRGSRFWIQDKGPIVESYIGFIESYRDPFGSRGEFEGFVAVVNKAMSAKFE RLVASAEQLLKELPWPPTFEKDKFLTPDFTSLDVLTFAGSGIPAGINIPNYDDLRQTEG FKNVSLGNVLAVAYATQREKLTFLEEDDKDLYILWKGPSFDVQVGLHELLGHGSGK LFVQDEKGAFNFDQETVINPETGEQIQSWYRSGETWDSKFSTIASSYEECRAESVGLY LCLHPQVLEIFGFEGADAEDVIYVNWLNMVRAGLLALEFYTPEAFNWRQAHMQARF VILRVLLEAGEGLVTITPTTGSDGRPDARVRLDRSKIRSVGKPALERFLRRLQVLKSTG DVAGGRALYEGYATVTDAPPECFLTLRDTVLLRKESRKLIVQPNTRLEGSDVQLLEY EASAAGLIRSFSERFPEDGPELEEILTQLATADARFWKGPSEAPSGQA SEQ ID No. 2-hDPP3 aa 474-493 (N-Cys)-immunization peptide with additional N-terminal Cystein CETVINPETGEQIQSWYRSGE SEQ ID No. 3-hDPP3 aa 477-482-epitope of AK1967 INPETG SEQ ID No. 4-hDPP3 aa 480-483 ETGE SEQ ID No. 5-variable region of murine AK1967 in heavy chain QVTLKESGPGILQPSQTLSLTCSFSGFSLSTSGMSVGWIRQPSGKGLEWLAHIWWNDN KSYNPALKSRLTISRDTSNNQVFLKIASVVTADTGTYFCARNYSYDYWGQGTTLTVS S SEQ ID No. 6-variable region of murine AK1967 in light chain DVVVTQTPLSLSVSLGDPASISCRSSRSLVHSIGSTYLHWYLQKPGQSPKLLIYKVSNR FSGVPDRFSGSGSGTDFTLKISRVEAEDLGVYFCSQSTHVPWTFGGGTKLEIK SEQ ID No. 7-CDR1 of murine AK1967 in heavy chain GFSLSTSGMS SEQ ID No. 8-CDR2 of murine AK1967 in heavy chain IWWNDNK SEQ ID No. 9-CDR3 of murine AK1967 in heavy chain ARNYSYDY SEQ ID No. 10-CDR1 of murine AK1967 in light chain RSLVHSIGSTY CDR2 of murine AK1967 in light chain KVS SEQ ID No. 11-CDR3 of murine AK1967 in light chain SQSTHVPWT SEQ ID No. 12-humanized AK1967-heavy chain sequence (IgG1κ backbone) MDPKGSLSWRILLFLSLAFELSYGQITLKESGPTLVKPTQTLTLTCTFSGFSLSTSGMS VGWIRQPPGKALEWLAHIWWNDNKSYNPALKSRLTITRDTSKNQVVLTMTNMDPV DTGTYYCARNYSYDYWGQGTLVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVK DYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHK PSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVV VDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKE YKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDI AVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALH NHYTQKSLSLSPG SEQ ID No. 13-humanized AK1967-light chain sequence (IgG1κ backbone) METDTLLLWVLLLWVPGSTGDIVMTQTPLSLSVTPGQPASISCKSSRSLVHSIGSTYL YWYLQKPGQSPQLLIYKVSNRFSGVPDRFSGSGSGTDFTLKISRVEAEDVGVYYCSQS THVPWTFGGGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQW KVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPV TKSFNRGEC