Proliferative signals for suppressor T cells. Helper cells stimulated with pokeweed mitogen in vitro produce a suppressor cell growth factor

Academic Article

Abstract

  • To define molecular signals elaborated by inducer populations supporting growth or differentiation of T8+ cells, we collected supernatants of pokeweed mitogen (PWM)-stimulated cultures depleted of T8+ cells. When added to purified T8+ cells, these supernatants caused significant proliferation. PWM plus interleukin 2 (IL-2) in amounts equivalent to those in the supernatant could not reconstitute the response caused by the supernatant. T8+ cells activated by supernatants obtained from PWM-pulsed T4+ cells suppressed fresh PWM cultures. Although exhibiting little proliferation, T8+ cells cultured for 6 d in PWM plus IL-2 still suppressed a fresh PWM response. The supernatants therefore contain an additional T suppressor cell growth factor (TsGF). Elaboration of TsGF required radiosensitive T4+Leu8+ cells. Molecular weight determination by high performance liquid chromatography gave a single peak of TsGF activity at ~8,000. Finally, whereas TsGF in the absence of IL-2 could not support the proliferation of T suppressor cells, it did cause T8+ cells to become strongly IL-2 receptor-positive.
  • Authors

    Published In

    Digital Object Identifier (doi)

    Author List

  • Fox EJ; Cook RG; Lewis DE; Rich RR
  • Start Page

  • 214
  • End Page

  • 220
  • Volume

  • 78
  • Issue

  • 1