Potentiation of the T lymphocyte response to mitogens. III. Properties of the mediator(s) from adherent cells.

摘要: Abstract Thymus lymphocyte activating factor was obtained in supernatants from cultures of human leukocytes or mouse peritoneal cells and exhibited the following properties: A. Lymphocyte activity stable for 2 hr at pH 5.5 10.5. A reduction noted 3.0. B. Up to two thirds could be precipitated by ammonium sulfate recovered a pattern different that total serum proteins. Maximum 60% saturation. C. is temperatures up 37 °C, but partially destroyed heating 60 80 °C. In presence normal serum, °C completely suppresses activity, due formation an inhibitory serum. D. not dialyzable. E. Chromatography on columns Sephadex G-50 G-100 showed localized fractions containing molecules estimated 5000 25,000 daltons with peak about 15,000 daltons. Similar fractionation patterns were cells, stimulated various agents, Short incubation (1 hr) insufficient stimulate thymocytes potentiate their response phytohemagglutinin.