Antibody response in patients with acute nonlymphocytic leukemia.

Lymphocytotoxic (LCT) and anti-red blood cell (ABO) antibodies were measured serially in adult patients with acute nonlymphocytic leukemia (ANLL) receiving induction chemotherapy. The antigenic stimulus was provided by multiple platelet transfusions, many of which were ABO incompatible. Comparison of pretherapy titers 4-6 weeks into therapy shows that 50% (19/38) of patients became LCT positive (cytotoxicity against greater than 10% of panel of cells) and 54% (19/35) had increases in ABO titers (greater than 2 tube dilution). A total of 66% of patients had significant rises in at least one antibody. ABO and LCT titers tended to vary in parallel although exceptions were noted. The development of anti) remission rate or duration, 3) type of therapy, 4) number of platelet transfusions, 5) time relationship between the antigenic stimulus and the initiation of cytotoxic therapy, and 6) skin test reactivity. Antibody responders tended to have higher pretreatment lymphocyte counts. The ability to develop a secondary antibody response does not appear to be a major prognostic factor in ANLL.