IFN-gamma-mediated prevention of graft-versus-host disease: pharmacodynamic studies and influence on proliferative capacity of chimeric spleen cells.
Recently we demonstrated that prolonged administration of IFN-gamma prevented the development of GVHD in a MHC-mismatched murine BMT model. Treatment with IFN-gamma allowed the development of mature donor-derived allo-tolerant immunocompetent cells in complete chimeric recipients. Here we present data on the pharmacodynamics of this cytokine-mediated protection against GVHD. Treatment with 50000 U IFN-gamma twice weekly for a period of 5 weeks, starting at the day of BMT, was shown to be the optimal treatment protocol, resulting in complete prevention of GVHD-related mortality. Treatment during 1 week with a three-fold higher weekly dose of IFN-gamma (50000 U six times) did not result in significantly improved survival. The start of IFN-gamma administration was a critical factor since a delay of 3 days from the time of BMT resulted in substantial GVHD-induced mortality. Furthermore, it was shown that IFN-gamma treatment inhibited the spontaneous and Con-A-induced proliferation of T cells at 7-14 days after BMT, which is the critical period for the initiation of acute GVHD. However, long-term survivors after IFN-gamma treatment showed a recovery of immunity in contrast to long-term survivors of saline-injected animals, as tested by Con-A responsiveness. It seems that injection of high dose IFN-gamma suppresses the response of potentially alloreactive donor T cells during what normally is the initiation phase of the GVH reaction (GVHR), resulting in the abrogation of GVHD.
Brok
H P
HP
Department of Immunobiology, Biomedical Primate Research Centre, Rijswijk, The Netherlands.
Vossen
J M
JM
Heidt
P J
PJ
D000818:Animals; D016026:Bone Marrow Transplantation; D002455:Cell Division / Q000187:drug effects; D002678:Chimera / Q000187:drug effects*; D003967:Diarrhea / Q000139:chemically induced; D005260:Female; D006086:Graft vs Host Disease / Q000517:prevention & control*; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D007371:Interferon-gamma / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D013154:Spleen / Q000166:cytology / Q000187:drug effects*; D013997:Time Factors
D007166:Immunosuppressive Agents; D007371:Interferon-gamma