CELL-MEDIATED CYTOTOXICITY RESULTS FROM, BUT MAY NOT BE CRITICAL FOR,PRIMARY ALLOGRAFT-REJECTION

Tumor cells insensitive to lysis through the Pas and TNF pathways were injected either subcutaneously or into the peritoneal cavities of all ogeneic perforin-less (PO) and perforin wild-type (P2) mice, In three of four cases, the tumors were rejected equally rapidly in both strain s of mice, Rejection was accompanied by vigorous in vitro cytotoxicity in P2, but not in PO mice, The rapid clearance of allografted cells i n mice where all three known cytolytic pathways are seriously compromi sed raises important questions about the involvement of cell-mediated cytotoxicity, as defined by current assay techniques, in primary allog raft rejection.