PROLONGATION OF SKIN ALLOGRAFT SURVIVAL IN MICE FOLLOWING ADMINISTRATION OF ALLOTRAP

Recently, Clayberger et al, demonstrated that ALLOTRAP, small syntheti c peptides derived from a conserved region of the alpha 1 helix of cer tain HLA class I molecules, inhibited human CTL responses in vitro. In rats, ALLOTRAP 07 therapy combined with a subtherapeutic dose of cycl osporine led to the permanent acceptance of heart allografts, In the p resent study, the effect of ALLOTRAP on the survival of skin allograft s in mice was studied, The tail skin of male C57B1/6 (H-2(b)) mice was grafted on the back of male CBA (H-2(k)) recipients. In untreated ani mals, the skin graft was rejected after 11.6+/-1.13 days (MST+/-SD). C yclosporine administered orally for 5 days after transplantation prolo nged graft survival to 13.1+/-2.13 days, ALLOTRAP 2702 prolonged graft survival to 16.57+/-2.15 days when administered orally for five days posttransplantation and to 18.86+/-0.38 when administered intraperiton eally until rejection, Thus, ALLOTRAP peptides derived from human MHC class I sequences, in addition to inhibiting human T cell responses in vitro, also prolong allograft survival in rats and mice.