Antimouse antibody response after OKT3 administration for steroid resistant rejection

OKT3 has become one of the more effective antirejection therapies for patients receiving kidney transplants. However, its usefulness is diminished or blocked by the development of antimouse/anti-OKT3 antibodies. We evaluated 17 children receiving OKT3 for steroid-resistant acute rejection for the development and persistence of antibodies after therapy. OKT3 was successful in reversing acute rejection in 14 of 17 patients. Eight children developed antimouse antibodies, 7 at a low titer (1:100). The retesting of all children 6 months later showed no detectable antibodies. Children develop anti-OKT3 antibodies at a rate similar to adults and with time lose detectable levels which may have significance if a subsequent course of OKT3 is needed.