Induction of sIg-Negative B Lymphocytes for Differentiation by PWM

It has been reported in the literature that PWM-responsive E lymphocytes are sIgM,⁺ sIgD^-, lack receptors for mouse erythrocytes, and are larger than PWM-negative lymphocytes. This paper describes the observation of B cells among the thymocytes from a patient with myasthenia gravis. In the thymocytes, actually no slg⁺cell wan found, and Staphylococous aureus Cowen strain I could not induoe the mononuolear cells in the thy-mus to differentiate. It was surprising that 6.9 per cent of the cells were BA-1 positive cells. At the same time, in the presence of PWM, 9680 ± 553 cells out of 1 × 10^--⁶ thymocytes could be induced to differentiate to immunoglobulin-secreting cells (ISC) in culture. This result suggests that PWM might be able to induce sIg^-B lymphocytes to differentiate as well.