1
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Cvetkovski F, Razavi R, Sellberg F, Berglund E, Berglund D. Siplizumab combination therapy with belatacept or abatacept broadly inhibits human T cell alloreactivity in vitro. Am J Transplant 2023; 23:1603-1611. [PMID: 37270108 DOI: 10.1016/j.ajt.2023.05.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/09/2023] [Accepted: 05/25/2023] [Indexed: 06/05/2023]
Abstract
Combined antigen-specific T cell receptor stimulation and costimulation are needed for complete T cell activation. Belatacept and abatacept are nondepleting fusion proteins blocking CD28/B7 costimulation, whereas siplizumab is a depleting antiCD2 immunoglobulin G1 monoclonal antibody targeting CD2/CD58 costimulation. Herein, the effect of siplizumab combination therapy with abatacept or belatacept on T cell alloreactivity in mixed lymphocyte reactions was investigated. In contrast to monotherapy, the combination of siplizumab with belatacept or abatacept induced near-complete suppression of T cell proliferation and increased the potency of siplizumab-mediated T cell inhibition. Furthermore, dual targeting of CD2 and CD28 costimulation enhanced the selective depletion of memory T cells compared with monotherapy. Although siplizumab monotherapy leads to significant regulatory T cell enrichment, high doses of cytotoxic T-lymphocyte-associated antigen 4 and a human IgG1 Fc fragment in the combination therapy reduced this effect. These results support the clinical evaluation of dual costimulation blockade, combining siplizumab with abatacept or belatacept, for the prophylaxis of organ transplant rejection and improvement of long-term outcomes following transplantation. Ongoing investigative research will elucidate when other forms of siplizumab-based dual costimulatory blockade may be able to induce similarly strong inhibition of T cell activation although still allowing for enrichment of regulatory T cells.
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Affiliation(s)
- Filip Cvetkovski
- Research and Development, ITB-MED AB, Stockholm, Sweden; Endocrine and Sarcoma Surgery Unit, Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden
| | - Ronia Razavi
- Research and Development, ITB-MED AB, Stockholm, Sweden
| | - Felix Sellberg
- Research and Development, ITB-MED AB, Stockholm, Sweden; Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Sweden
| | - Erik Berglund
- Research and Development, ITB-MED AB, Stockholm, Sweden; Endocrine and Sarcoma Surgery Unit, Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden; Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute, Stockholm, Sweden
| | - David Berglund
- Research and Development, ITB-MED AB, Stockholm, Sweden; Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Sweden.
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2
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Binder C, Sellberg F, Cvetkovski F, Berg S, Berglund E, Berglund D. Siplizumab Induces NK Cell Fratricide Through Antibody-Dependent Cell-Mediated Cytotoxicity. Front Immunol 2021; 12:599526. [PMID: 33643309 PMCID: PMC7904868 DOI: 10.3389/fimmu.2021.599526] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 01/05/2021] [Indexed: 12/17/2022] Open
Abstract
The glycoprotein CD2 is expressed on T and NK cells and contributes to cell-cell conjugation, agonistic signaling and actin cytoskeleton rearrangement. CD2 has previously been shown to have an important function in natural NK cell cytotoxicity but to be expendable in antibody-mediated cytotoxicity. Siplizumab is a monoclonal anti-CD2 IgG1 antibody that is currently undergoing clinical trials in the field of transplantation. This study investigated the effect of CD2 binding and Fc γ receptor binding by siplizumab (Fc-active) and Fc-silent anti-CD2 monoclonal antibodies in allogeneic mixed lymphocyte reaction and autologous lymphocyte culture. Further, induction of NK cell fratricide and inhibition of natural cytotoxicity as well as antibody-dependent cytotoxicity by these agents were assessed. Blockade of CD2 via monoclonal antibodies in the absence of Fc γ receptor binding inhibited NK cell activation in allogeneic mixed lymphocyte reaction. In contrast, siplizumab increased NK cell activation in both mixed lymphocyte reaction and autologous lymphocyte culture due to FcγRIIIA binding. However, experiments using purified NK cells did not show an inhibitory effect of CD2 blockade on natural cytotoxicity or antibody-dependent cytotoxicity. Lastly, it was shown that siplizumab induces NK cell fratricide. Concluding, siplizumab is a promising biopharmaceutical drug candidate for depletion of T and NK cells with minimal off-target effects.
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Affiliation(s)
- Christian Binder
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
- Research and Development, ITB-Med AB, Stockholm, Sweden
| | - Felix Sellberg
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
- Research and Development, ITB-Med AB, Stockholm, Sweden
| | | | - Stefan Berg
- Research and Development, ITB-Med AB, Stockholm, Sweden
| | - Erik Berglund
- Research and Development, ITB-Med AB, Stockholm, Sweden
- Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute and Karolinska University Hospital, Stockholm, Sweden
| | - David Berglund
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
- Research and Development, ITB-Med AB, Stockholm, Sweden
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3
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Binder C, Cvetkovski F, Sellberg F, Berg S, Paternina Visbal H, Sachs DH, Berglund E, Berglund D. CD2 Immunobiology. Front Immunol 2020; 11:1090. [PMID: 32582179 PMCID: PMC7295915 DOI: 10.3389/fimmu.2020.01090] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 05/05/2020] [Indexed: 01/21/2023] Open
Abstract
The glycoprotein CD2 is a costimulatory receptor expressed mainly on T and NK cells that binds to LFA3, a cell surface protein expressed on e.g., antigen-presenting cells. CD2 has an important role in the formation and organization of the immunological synapse that is formed between T cells and antigen-presenting cells upon cell-cell conjugation and associated intracellular signaling. CD2 expression is upregulated on memory T cells as well as activated T cells and plays an important role in activation of memory T cells despite the coexistence of several other costimulatory pathways. Anti-CD2 monoclonal antibodies have been shown to induce immune modulatory effects in vitro and clinical studies have proven the safety and efficacy of CD2-targeting biologics. Investigators have highlighted that the lack of attention to the CD2/LFA3 costimulatory pathway is a missed opportunity. Overall, CD2 is an attractive target for monoclonal antibodies intended for treatment of pathologies characterized by undesired T cell activation and offers an avenue to more selectively target memory T cells while favoring immune regulation.
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Affiliation(s)
- Christian Binder
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden.,Research and Development, ITB-Med AB, Stockholm, Sweden
| | | | - Felix Sellberg
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden.,Research and Development, ITB-Med AB, Stockholm, Sweden
| | - Stefan Berg
- Research and Development, ITB-Med AB, Stockholm, Sweden
| | - Horacio Paternina Visbal
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden.,Research and Development, ITB-Med AB, Stockholm, Sweden
| | - David H Sachs
- Research and Development, ITB-Med AB, Stockholm, Sweden.,Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, United States
| | - Erik Berglund
- Research and Development, ITB-Med AB, Stockholm, Sweden.,Division of Transplantation Surgery, CLINTEC, Karolinska Institute, and Department of Transplantation Surgery, Karolinska University Hospital, Stockholm, Sweden
| | - David Berglund
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden.,Research and Development, ITB-Med AB, Stockholm, Sweden
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4
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Podestà MA, Binder C, Sellberg F, DeWolf S, Shonts B, Ho SH, Obradovic A, Waffarn E, Danzl N, Berglund D, Sykes M. Siplizumab selectively depletes effector memory T cells and promotes a relative expansion of alloreactive regulatory T cells in vitro. Am J Transplant 2020; 20:88-100. [PMID: 31319439 PMCID: PMC6940533 DOI: 10.1111/ajt.15533] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 07/02/2019] [Accepted: 07/10/2019] [Indexed: 01/25/2023]
Abstract
Siplizumab, a humanized anti-CD2 monoclonal antibody, has been used in conditioning regimens for hematopoietic cell transplantation and tolerance induction with combined kidney-bone marrow transplantation. Siplizumab-based tolerance induction regimens deplete T cells globally while enriching regulatory T cells (Tregs) early posttransplantation. Siplizumab inhibits allogeneic mixed-lymphocyte reactions (MLRs) in vitro. We compared the impact of siplizumab on Tregs versus other T cell subsets in HLA-mismatched allogeneic MLRs using PBMCs. Siplizumab predominantly reduced the percentage of CD4+ and CD8+ effector memory T cells, which express higher CD2 levels than naïve T cells or resting Tregs. Conversely, siplizumab enriched proliferating CD45RA- FoxP3HI cells in MLRs. FoxP3 expression was stable over time in siplizumab-containing cultures, consistent with enrichment for bona fide Tregs. Consistently, high-throughput TCRβ CDR3 sequencing of sorted unstimulated and proliferating T cells in MLRs revealed selective expansion of donor-reactive Tregs along with depletion of donor-reactive CD4+ effector/memory T cells in siplizumab-containing MLRs. These results indicate that siplizumab may have immunomodulatory functions that may contribute to its success in tolerance-inducing regimens. Our studies also confirm that naïve in addition to effector/memory T cells contribute to the allogeneic MLR and mandate further investigation of the impact of siplizumab on alloreactive naïve T cells.
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Affiliation(s)
- Manuel Alfredo Podestà
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, NY, USA.,Current affiliations: Università degli Studi di Milano, Milan, Italy and Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Christian Binder
- ITB-Med AB, Sonja Kovalevskys gata 4, 113 66 Stockholm, Sweden,Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Felix Sellberg
- ITB-Med AB, Sonja Kovalevskys gata 4, 113 66 Stockholm, Sweden,Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Susan DeWolf
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, NY, USA
| | - Brittany Shonts
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, NY, USA
| | - Siu-Hong Ho
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, NY, USA
| | - Aleksandar Obradovic
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, NY, USA
| | - Elizabeth Waffarn
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, NY, USA
| | - Nichole Danzl
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, NY, USA
| | - David Berglund
- ITB-Med AB, Sonja Kovalevskys gata 4, 113 66 Stockholm, Sweden,Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Megan Sykes
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, NY, USA.,Department of Microbiology & Immunology, Columbia University Medical Center, NY, USA and Department of Surgery, Columbia University Medical Center, NY, USA
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5
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Berglund E, Alonso-Guallart P, Danton M, Sellberg F, Binder C, Fröbom R, Berglund D, Llore N, Sakai H, Iuga A, Ekanayake-Alper D, Reimann KA, Sachs DH, Sykes M, Griesemer A. Safety and pharmacodynamics of anti-CD2 monoclonal antibody treatment in cynomolgus macaques - an experimental study. Transpl Int 2019; 33:98-107. [PMID: 31523849 DOI: 10.1111/tri.13524] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 05/25/2019] [Accepted: 09/09/2019] [Indexed: 11/30/2022]
Abstract
Anti-CD2 treatment provides targeted immunomodulatory properties that have demonstrated clinical usefulness to condition the immune system and to treat transplant rejection. The treatment is species-specific due to structural CD2 antigen differences between nonhuman primates and humans. Herein, we report the safety profile and efficacy of two modifications of the same anti-CD2 monoclonal antibody in cynomolgus macaques. Twelve subjects received one i.v. anti-CD2 (of rat or rhesus type) dose each, range 1-4 mg/kg, and were followed for 1-7 days. Treatment effects were evaluated with flow cytometry on peripheral blood and histopathological evaluation of secondary lymphoid organs. In vitro inhibitory activity on primary MHC disparate mixed lymphocyte reactions (MLRs) was determined. Upon anti-CD2 treatment, CD4+ , CD8+ memory subsets were substantially depleted. Naïve T cells and Tregs were relatively spared and exhibited lower CD2 expression than memory T cells. Early immune reconstitution was noted for naïve cells, while memory counts had not recovered after one week. Both antibodies displayed a concentration-dependent MLR inhibition. Lymph node examination revealed no significant lymphocyte depletion. None of the animals experienced any significant study drug-related adverse events. This study outlines the safety and pharmacodynamic profile of primate-specific anti-CD2 treatment, relevant for translation of anti-CD2-based animal models into clinical trials.
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Affiliation(s)
- Erik Berglund
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA.,Division of Transplantation Surgery, Department of Transplantation Surgery, Karolinska Institute, CLINTEC, Karolinska University Hospital, Stockholm, Sweden
| | - Paula Alonso-Guallart
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA
| | - Makenzie Danton
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA
| | - Felix Sellberg
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Christian Binder
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Robin Fröbom
- Division of Transplantation Surgery, Department of Transplantation Surgery, Karolinska Institute, CLINTEC, Karolinska University Hospital, Stockholm, Sweden
| | - David Berglund
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Nathaly Llore
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA
| | - Hiroshi Sakai
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA
| | - Alina Iuga
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA
| | - Dilrukshi Ekanayake-Alper
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA
| | - Keith A Reimann
- MassBiologics, University of Massachusetts Medical School, Boston, MA, USA
| | - David H Sachs
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA
| | - Megan Sykes
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA.,Department of Surgery, Columbia University Medical Center, New York, NY, USA.,Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, USA
| | - Adam Griesemer
- Department of Medicine, Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA.,Department of Surgery, Columbia University Medical Center, New York, NY, USA
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6
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Sellberg F, Berglund D, Binder C, Hope J, Fontenot J, Griesemer A, Sykes M, Sachs DH, Berglund E. Pharmacokinetic and pharmacodynamic study of a clinically effective anti-CD2 monoclonal antibody. Scand J Immunol 2019; 91:e12839. [PMID: 31630416 DOI: 10.1111/sji.12839] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/14/2019] [Accepted: 10/15/2019] [Indexed: 12/22/2022]
Abstract
The humanized IgG1κ monoclonal antibody siplizumab and its rat parent monoclonal IgG2b antibody BTI-322 are directed against the CD2 antigen. Siplizumab is species-specific, reacting with human and chimpanzee cells but not with cells from any other species, including other non-human primates. Because siplizumab treatment has recently shown great potential in clinical transplantation, we now present the results of our previous pharmacokinetic, pharmacodynamic and safety studies of both antibodies. Fourteen chimpanzees received 1-3 doses of 0.143 to 5.0 mg/kg iv The effects were followed with flow cytometry on peripheral lymphocytes and staining of lymph nodes. Side effects were recorded. Serum antibody concentrations were followed. Across the doses, a rapid, transient depletion of CD2, CD3, CD4 and CD8 lymphocytes and NK cells was observed for both antibodies. Immune reconstitution was more rapid for BTI-322 compared to siplizumab. Paracortical lymph node T cell depletion was moderate, estimated at 45% with doses of >0.6 mg/kg. Restoration of lymph node architecture was seen after two weeks to two months for all animals. All four subjects receiving BTI-322 experienced AEs on the first dosing day, while the eight subjects dosed with siplizumab experienced few mild, transient AEs. Infusion with siplizumab and BTI-322 resulted in rapid depletion of CD2+ cells in circulation and tissue. Siplizumab had a longer t1/2 and fewer AEs compared to BTI-322.
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Affiliation(s)
- Felix Sellberg
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - David Berglund
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - Christian Binder
- Department of Immunology, Genetics and Pathology, Section of Clinical Immunology, Uppsala University, Uppsala, Sweden
| | - James Hope
- Independent BioTechnology Consultants, Chicago, IL, USA
| | - Jane Fontenot
- University of Louisiana at Lafayette New Iberia Primate Research Center, New Iberia, LA, USA
| | - Adam Griesemer
- Department of Surgery, Columbia Center for Translational Immunology, Columbia University Medical Center, Columbia University, New York, NY, USA
| | - Megan Sykes
- Department of Surgery, Columbia Center for Translational Immunology, Columbia University Medical Center, Columbia University, New York, NY, USA
| | - David H Sachs
- Department of Surgery, Columbia Center for Translational Immunology, Columbia University Medical Center, Columbia University, New York, NY, USA
| | - Erik Berglund
- Department of Surgery, Columbia Center for Translational Immunology, Columbia University Medical Center, Columbia University, New York, NY, USA.,Division of Transplantation Surgery, Department of Transplantation Surgery, Karolinska Institute, CLINTEC, Karolinska University Hospital, Stockholm, Sweden
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7
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Erben U, Pawlowski NN, Doerfel K, Loddenkemper C, Hoffmann JC, Siegmund B, Kühl AA. Targeting human CD2 by the monoclonal antibody CB.219 reduces intestinal inflammation in a humanized transfer colitis model. Clin Immunol 2015; 157:16-25. [DOI: 10.1016/j.clim.2015.01.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 12/18/2014] [Accepted: 01/02/2015] [Indexed: 01/12/2023]
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8
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Monoclonal antibodies generated by DNA immunization recognize CD2 from a broad range of primates. Immunol Cell Biol 2009; 87:413-8. [PMID: 19204736 DOI: 10.1038/icb.2009.4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Using heterologous prime-boost (DNA immunization followed by immunization with transfected cells), we have generated depleting mouse anti-baboon CD2 monoclonal antibodies (mAb). These anti-CD2 mAb recognized a diverse range of primate CD2 from New World monkeys and Old World monkeys to humans and have potent immunosuppressive activity for human allo-MLR responses and anti-tetanus-toxoid recall responses. There was no upregulation of activation markers or release of cytokines when the mAb were incubated with human peripheral blood mononuclear cells. Using chimeric NOD-SCID IL2rgamma(null) mice, the mAb were shown to deplete human and cynomolgus monkey T cells in vivo. These anti-CD2 mAb may therefore be important immunological tools in allo- and xenotransplantation.
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9
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Boysen P, Olsen I, Berg I, Kulberg S, Johansen GM, Storset AK. Bovine CD2-/NKp46+ cells are fully functional natural killer cells with a high activation status. BMC Immunol 2006; 7:10. [PMID: 16643649 PMCID: PMC1482717 DOI: 10.1186/1471-2172-7-10] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2005] [Accepted: 04/27/2006] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Natural killer (NK) cells in the cow have been elusive due to the lack of specific NK cell markers, and various criteria including a CD3-/CD2+ phenotype have been used to identify such cells. The recent characterization of the NK-specific NKp46 receptor has allowed a more precise definition of bovine NK cells. NK cells are known as a heterogeneous cell group, and we here report the first functional study of bovine NK cell subsets, based on the expression of CD2. RESULTS Bovine CD2- NK cells, a minor subset in blood, proliferated more rapidly in the presence of IL-2, dominating the cultures after a few days. Grown separately with IL-2, CD2- and CD2+ NK cell subsets did not change CD2 expression for at least two weeks. In blood, CD2- NK cells showed a higher expression of CD44 and CD25, consistent with a high activation status. A higher proportion of CD2- NK cells had intracellular interferon-gamma in the cytoplasm in response to IL-2 and IL-12 stimulation, and the CD2- subset secreted more interferon-gamma when cultured separately. Cytotoxic capacity was similar in both subsets, and both carried transcripts for the NK cell receptors KIR, CD16, CD94 and KLRJ. Ligation by one out of two tested anti-CD2 monoclonal antibodies could trigger interferon-gamma production from NK cells, but neither of them could alter cytotoxicity. CONCLUSION These results provide evidence that bovine CD2- as well as CD2+ cells of the NKp46+ phenotype are fully functional NK cells, the CD2- subset showing signs of being more activated in the circulation.
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Affiliation(s)
- Preben Boysen
- Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, P.O.Box 8146 Dep., N-0033 Oslo, Norway
| | - Ingrid Olsen
- Department of Animal Health, National Veterinary Institute, P.O.Box 8156 Dep., N-0033 Oslo, Norway
| | - Ingvild Berg
- Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, P.O.Box 8146 Dep., N-0033 Oslo, Norway
| | - Siri Kulberg
- Department of Animal Health, National Veterinary Institute, P.O.Box 8156 Dep., N-0033 Oslo, Norway
| | - Grethe M Johansen
- Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, P.O.Box 8146 Dep., N-0033 Oslo, Norway
| | - Anne K Storset
- Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, P.O.Box 8146 Dep., N-0033 Oslo, Norway
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10
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Abstract
The year 2004 represents a milestone for the biosensor research community: in this year, over 1000 articles were published describing experiments performed using commercially available systems. The 1038 papers we found represent an approximately 10% increase over the past year and demonstrate that the implementation of biosensors continues to expand at a healthy pace. We evaluated the data presented in each paper and compiled a 'top 10' list. These 10 articles, which we recommend every biosensor user reads, describe well-performed kinetic, equilibrium and qualitative/screening studies, provide comparisons between binding parameters obtained from different biosensor users, as well as from biosensor- and solution-based interaction analyses, and summarize the cutting-edge applications of the technology. We also re-iterate some of the experimental pitfalls that lead to sub-optimal data and over-interpreted results. We are hopeful that the biosensor community, by applying the hints we outline, will obtain data on a par with that presented in the 10 spotlighted articles. This will ensure that the scientific community at large can be confident in the data we report from optical biosensors.
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Affiliation(s)
- Rebecca L Rich
- Center for Biomolecular Interaction Analysis, University of Utah, Salt Lake City, UT 84132, USA
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