[Circulating immune complexes in human leukemias].

Occurrence of immune complexes in leukemia has been investigated by the 125I-Clq-binding test. A highly significant serum Clq-binding activity (Clq-BA) was demonstrated in 37% of patients with acute myelocytic leukemia, in 23% of patients with acute lymphocyte leukemia,and in 32% of those in blastic crisis of chronic myelocytic leukemia. Such a high Clq-BA is found only in 13% of cases with chronic leukemia. Incidence of increased serum Clq-BA is significantly higher during the blastic stage of leukemia than in complete remission. There is no correlation between the elevated Clq-BA and infections complicating acute leukemia, or with the chemotherapy given to the patients. The Clq-binding material exhibits properties similar to those of immune complexes.