Functional Heterogeneity among the T-Derived Lymphocytes of the Mouse

Abstract

A number of T cell functions were followed in mice after thymectomy in adult life. It was found that T cells involved in these functions could be divided roughly into two subpopulations: one whose activity was relatively long-lived (longer than 20 weeks) and one, relatively short-lived (on the order of a few weeks). In the long-lived class were those T cells involved in the helper function in the primary IgM and IgG responses to SRBC in vivo and in vitro. Priming for the secondary demonstration of helper activity or delayed hypersensitivity specific for SRBC seemed to involve both classes, although the contribution from the short-lived class was greater. These findings are consistent with models for T cell heterogeneity in which a short-lived population of T cells contains precursors distinct from a second long-lived population containing memory cells. Both classes can apparently contribute to a pool of activated effector cells in a process driven by antigenic stimulation.