BW 5147 supernatants suppress Con A stimulation of mouse spleen cells

Conditioned medium from mouse T lymphoma BW 5147 cell cultures suppressed Con A-stimulated DNA synthesis in cultures of mouse spleen cells. Supernatants from control mouse T cell lymphoma EL-4 were not effective. Conditioned medium from BW 5147 cells did not inhibit DNA synthesis in control cultures of IL-2-dependent mouse T cells or mouse leukaemias of T cell or erythroblastic origin. It is suggested that constitutive production of a soluble suppressor factor by BW 5147 lymphoma cells is responsible for the effects observed.