Delayed low-level calcineurin inhibition promotes allospecific tolerance induction by posttransplantation donor leukocyte infusion.
BACKGROUND
Donor lymphocytes infused after organ transplantation can have strong immunoregulatory effects. Application of such protocols for transplant tolerance induction in a clinical setting will, however, require combination of specific immunomodulatory strategies with nonspecific immunosuppressive medication for safety reasons. The aim of this study was to analyze the effects of immunosuppressive treatment on tolerance induction protocols by posttransplantation donor lymphocyte infusion.


METHODS
The interaction of postoperative donor leukocyte infusion with different types, dosage, and timing of immunosuppressive drugs were studied in a rat model of heart transplantation.


RESULTS
Tolerance could be achieved if donor cell infusion was combined with delayed, but not immediate, low-dose cyclosporine treatment, and this was associated with activation and apoptosis of host lymphocytes. In contrast, combinations with an antibody against the interleukin 2 receptor led to long-term graft survival but severe chronic rejection, and combinations with high-dose cyclosporine or sirolimus led to acute rejection.


CONCLUSIONS
Postoperative donor leukocyte infusion is a potential way for tolerance induction, but the type, dose, and timing of medication are highly critical for its efficacy.
Tsui
Tung-Yu
TY
Klinik für Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany.
Jäger
Mark D
MD
Deiwick
Andrea
A
Aselmann
Heiko
H
Neipp
Michael
M
Fan
Sheung-Tat
ST
Schlitt
Hans J
HJ
D000818:Animals; D000906:Antibodies / Q000627:therapeutic use; D019703:Calcineurin / Q000235:genetics* / Q000502:physiology; D016572:Cyclosporine / Q000627:therapeutic use; D005260:Female; D006084:Graft Rejection / Q000276:immunology; D006085:Graft Survival / Q000276:immunology; D016027:Heart Transplantation / Q000276:immunology* / Q000473:pathology; D007165:Immunosuppression Therapy / Q000379:methods; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D017708:Leukocyte Transfusion; D017710:Lymphocyte Transfusion; D008297:Male; D051381:Rats; D011914:Rats, Inbred BN; D011917:Rats, Inbred Lew; D015375:Receptors, Interleukin-2 / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020123:Sirolimus / Q000627:therapeutic use; D013154:Spleen / Q000276:immunology; D014184:Transplantation, Homologous / Q000276:immunology*
D000906:Antibodies; D007166:Immunosuppressive Agents; D015375:Receptors, Interleukin-2; D016572:Cyclosporine; D019703:Calcineurin; D020123:Sirolimus