ACCEPTANCE OF PRIMARY SKIN-GRAFT AFTER TREATMENT WITH ANTI-INTERCELLULAR ADHESION MOLECULE-1 AND ANTILEUKOCYTE FUNCTION-ASSOCIATED ANTIGEN-1 MONOCLONAL-ANTIBODIES IN MICE

Although a short-term blockade of intercellular adhesion molecule-1 (I CAM-1) and leukocyte function-associated antigen-1 (LFA-1) adhesion al lows induction of specific tolerance to solid organs, their effect on primary skin allografts is not yet known. Effects of anti-ICAM-1 and a nti-LFA-1 monoclonal antibodies (mAb) on primary skin allograft surviv al were investigated. Recipient mice were treated with either a combin ation of anti-ICAM-1 and anti-LFA-1 mAbs or a control mAb for the firs t 22 days. The survival of BALB/c skin in the C3H/He recipient was not prolonged. Subsequently, MHC class I (bm1)- or class II (bm12)-dispar ate skin grafts were transplanted into C57BL/6 mice. Remarkable prolon gation was observed in these combinations. Four of 10 bm12 grafts and 4 of 9 bm1 grafts were accepted for more than 120 days. These results suggest that mouse strain combination is an important factor for skin graft acceptance. We suggest that unique immunogenicity and a lack of vascularization of skin allografts account for the weak immunosuppress ion produced by anti-adhesion molecule mAbs.