In vitro response of lymphocytes to phytohemagglutinin (PHA) and serum levels of immunoglobulins during remission of acute leukemia.

The study group consisted of 13 patients, including 5 in complete remission and 8 in incomplete hematologic remission. Six patients had a pause in therapy, and the remaining ones were continuing maintenance therapy. In all cases production of IgG, IgA and IgM immunoglobulins was maintained. Response of lymphocytes to PHA in vitro was normal in 7 patients, mainly in those who had a pause in treatment. The test results were uncorrelated with hematologic status. Both tests showed preserved humoral immunity and delyed hypersensitivity in the early period of remission and had no prognositc value.