Cyclosporine preserves the anergic state of human T cells induced by costimulation blockade in vitro.
BACKGROUND
Costimulation blockade based tolerance-inducing therapies might be disrupted by adjunct conventional immunosuppressive drug use. In the current study, we evaluated the compatibility of various immunosuppressive agents on costimulation blockade-based immunosuppression and T-cell anergy induction of human alloreactive T-cells in vitro. T-cell anergy is crucial in transplantation tolerance.


METHODS
T cell anergy was induced in human mixed lymphocyte cultures in vitro, by monoclonal antibodies directed against the costimulatory ligands CD40 and CD86. The effect of coadministration of conventional immunosuppressive drugs (CsA, rapamycin or FK506) on the inhibitory potential of costimulation blockade and the induction and maintenance of T cell anergy was analyzed.


RESULTS
We found that monoclonal antibodies against CD40 and CD86 and the simultaneous use of conventional immunosuppressive drugs resulted in strong immunosuppression of proliferation and cytokine production. Rapamycin, in contrast to FK506 and CsA, facilitated T-cell apoptosis. However, drug cotreatment prevented costimulation blockade induced T-cell anergy. Induction of human T-cell anergy in vitro required approximately 5 days of culture. Coadministration of drugs at day 5 after the start of mAb treatment, when anergy was established, did not increase the immunosuppressive effect of mAb treatment. But interestingly, in the majority of experiments, in contrast to rapamycin and FK506, CsA did not affect the anergic state when given after T-cell anergy induction. Moreover, the cell death facilitating potential of rapamycin vanished when used later after T-cell activation.


CONCLUSIONS
Timing and choice of conventional drug are crucial in the success of costimulation blockade-based tolerance induction therapies.
Koenen
Hans J P M
HJ
Department of Blood Transfusion and Transplantation Immunology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. H.Koenen@abti.umcn.nl
Fasse
Esther
E
Joosten
Irma
I
D000911:Antibodies, Monoclonal / Q000494:pharmacology; D015703:Antigens, CD / Q000276:immunology; D017209:Apoptosis / Q000187:drug effects; D051940:B7-2 Antigen; D019013:CD40 Antigens / Q000276:immunology; D002453:Cell Cycle / Q000187:drug effects; D002478:Cells, Cultured; D017635:Clonal Anergy / Q000187:drug effects*; D016572:Cyclosporine / Q000494:pharmacology*; D016207:Cytokines / Q000378:metabolism; D004359:Drug Therapy, Combination; D004797:Enzyme-Linked Immunosorbent Assay; D005500:Follow-Up Studies; D006801:Humans; D007165:Immunosuppression Therapy; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D066298:In Vitro Techniques; D008213:Lymphocyte Activation / Q000187:drug effects; D008562:Membrane Glycoproteins / Q000276:immunology; D017634:Self Tolerance / Q000187:drug effects*; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D013997:Time Factors
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D051940:B7-2 Antigen; D019013:CD40 Antigens; C497964:CD86 protein, human; D016207:Cytokines; D007166:Immunosuppressive Agents; D008562:Membrane Glycoproteins; D016572:Cyclosporine