In vitro lymphocyte response to phytohemagglutinin and pokeweed mitogen in Hodgkin's disease. An electron microscopic and functional study.

Abstract

Lymphocytes from eight patients with Hodgkin's disease were incubated with phytohemagglutinin (PHA) or pokeweed mitogen (PWM) over 7 days. Thymidine incorporation into DNA and ultrastructural features of transformed cells were studied. Response to these mitogens was either normal or diminished and/or delayed. In seven patients lymphocyte response to PHA was paralleled by a corresponding response to PWM. PHA-transformed lymphocytes showed fine structural features similar to transformed normal cells. After PWM stimulation, blast cells and plasmacytoid cells in various stages of differentiation were observed. The number of transformed cells corresponded to the magnitude of thymidine incorporation and in cultures with normal PWM response, plasmacytoid cells occurred with almost normal frequency. If the specificity of the mitogens is as postulated, then patients with Hodgkin's disease do not have a selective loss of T lymphocytes. Furthermore, the findings suggest that in some patients there may be a functional impairment of both T and B lymphocytes.