Human alloreactive CTL clones: loss and reacquisition of specific cytolytic activity can be regulated by...

In this communication, we demonstrate that human alloreactive CTL at the clonal level, can undergo reversible processes vis-a-vis lytic function: from a highly lytic phase to a nonlytic quiescent phase and back to a lytic phase. "Reversion" and reacquisition of function can be controlled by removing or adding back a chromatographically purified product of a human interleukin 2 gene (rIL 2) that appears to serve, either directly or indirectly, as a lysis-inducing signal for these CTL.