Abstract
Mononuclear cells which were isolated from rheumatoid synovial effusions and cultured without prior separation failed to support the growth of herpes simplex virus (HSV). However, subpopulations of T lymphocytes separated on the basis of cell size or receptors for sheep red cells were, in isolation, permissive for this virus. Virus growth in these permissive cells was blocked by cocultivation with the remaining mononuclear cell populations.