T and B cells in myelomatosis.

The majority of treated patients with myelomatosis had a significantly decreased number of T cells as measured by both lymphocyte stimulation to phytohaemagglutinin (PHA) and by their ability to form spontaneous rosettes with sheep red blood cells (SRBC). Seven untreated patients also had markedly depressed T cells. On the other hand, B-cell numbers' were significantly increased in the majority of the patients as judged by increased lymphocyte stimulation to pokeweed mitogen (PWM) and the markedly increased numbers of rosettes that were formed with antibody-coated complement activated SRBC, as well as by immunofluorescence cell markers to monospecific immunoglobulin antiserum.