T-cell regulation of pokeweed-mitogen-induced polyclonal immunoglobulin production in mice. III. Role of Lyt 1+2- non-helper T cells in the suppression.

A large number of cells which can replicate vesicular stomatitis virus (VSV) were generated in pokeweed mitogen (PWM)-stimulated cultures of normal mouse spleen cells. The optimal dose of PWM for the generation of VSV-replicating cells was within the range 25 and 50 micrograms/ml, which had previously been shown to be optimal for the induction of suppressor cells. The VSV-replicating cells in this system were shown to be Thy 1+ and Lyt 1+2-. These cells, however, were unlikely to be helper T cells, but may be a subset of T cells involved in suppression. Thus, inoculation of VSV into a PWM-stimulated culture of spleen cells resulted in marked augmentation of polyclonal immunoglobulin production. Further, it was shown that the suppressive activity of T cells which had been precultured with a high dose of PWM was abolished by the infection with this virus.