Establishment and characterization of continuous murine non-specific suppressor T cell lines

Normal mouse spleen cells were activated by Con A and suppressor T cells were enriched by the use of peanut agglutinin (PNA). Cells of the enriched suppressor T cell fraction were further cultured in a medium containing T cell growth factor (TCGF) and the suppressor T cell lines were established. These cell lines have been growing in culture for more than one year and retained surface characteristics of Thy-1+, Lyt-1-, 2- and bear receptor sites for PNA. The suppressor clones exerted an inhibitory effect on in vitro antigen specific and antigen nonspecific PFC responses. The culture supernatant of these clones had a suppressive effect on the in vitro humoral responses, indicating that a soluble factor mediates at least partly the suppressive activity of the antigen nonspecific suppressor T cells. Moreover, it was revealed that the suppressor cells must exist at an early stage of PFC culture to exert their activity.