Development of specific nonreactivity in human cadaveric renal allograft recipients.

The development of specific nonreactivity and mixed leukocyte culture blocking factor activity (MLC-BFA) was serially studied in three cadaveric renal allograft recipients. All patients developed hypo and/or nonreactivity in the MLC reaction to the specific donor but not to an indifferent donor. Specific hypo and/or nonreactivity observed in the MLC reaction was independent of recipient's response to PHA which remained normal. Broad reacting MLC-BFA declined and subsequently disappeared after the state of specific nonreactivity was achieved. Several allograft rejection crisis occurred during the active stage, but these crises subsided once the nonreactivity was achieved.