Herpes simplex virus-specific lymphoproliferation: an analysis of the involvement of lymphocyte subsets.

Herpes simplex virus (HSV)-immune murine splenocytes incorporated significant levels of tritiated thymidine when incubated with UV-inactivated, heat-inactivated, and active preparations of HSV. Normal splenocytes incubated with the HSV preparations did not exhibit such proliferation. Maximum incorporation by the immune splenocytes occurred on the fifth day of culture and was mediated by Thy-1+, Lyt-1+, and Lyt-2+ cells. Attempts to correlate lymphoproliferation with other HSV-specific cellular immune responses demonstrated the complexity of this response. While T cells mediating delayed type hypersensitivity responses and cytotoxic T lymphocytes were involved in the lymphoproliferative response, neither could be considered as being exclusively associated with lymphoproliferation. Instead, lymphoproliferation appeared to be indicative of HSV-specific Lyt-1+ helper cells. Evidence was also presented that suppressor cells appeared to be involved in the regulation of the lymphoproliferative response.