title: Immunologic and molecular characterizations of T cell-derived T cell activating factor.
abstract: Culture supernatants from several subclones of a human T hybrid line (24A) stimulated with PMA showed co-stimulatory activity in the proliferation of Con A-stimulated murine thymocytes, but did not show any IL 2 activity. Some subclones did not show co-stimulatory activity even when stimulated with PMA, excluding the possibility of a carry-over effect. The factor found in the culture supernatants increased IL 2 production in normal T cells stimulated with a suboptimal concentration of PHA. The factor also induced IL 2 production in a T hybrid clone, T-394.1, when the latter was stimulated with a suboptimal concentration of mitogens, indicating a direct effect by this T cell-derived factor on mitogen-stimulated T cells inducing IL 2 production. This factor also induced the generation of other lymphokines such as BCDF and IFN-gamma. Northern blot analysis showed that the factor induced an increase in mRNA for IL 2 as well as IL 2 receptor. These results indicated that T cells could secrete a factor with IL 1-like activity. However, Northern blot analysis showed that mRNA from a T hybrid clone does not cross-react with cDNA for IL 1 (beta) derived from human monocytes.
authors.forename: M
authors.initials: M
authors.lastname: Okada
authors.forename: N
authors.initials: N
authors.lastname: Yoshimura
authors.forename: Y
authors.initials: Y
authors.lastname: Ichimori
authors.forename: S
authors.initials: S
authors.lastname: Kishimoto
authors.forename: S
authors.initials: S
authors.lastname: Nakai
authors.forename: N
authors.initials: N
authors.lastname: Nishino
authors.forename: T
authors.initials: T
authors.lastname: Kishimoto
mesh_terms: D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface / Q000096:biosynthesis; D003429:Cross Reactions; D006801:Humans; D006825:Hybridomas / Q000378:metabolism; D007371:Interferon-gamma / Q000096:biosynthesis; D007375:Interleukin-1 / Q000302:isolation & purification / Q000502:physiology*; D007376:Interleukin-2 / Q000096:biosynthesis / Q000302:isolation & purification / Q000502:physiology; D055646:Killer Factors, Yeast; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D009693:Nucleic Acid Hybridization; D011506:Proteins / Q000502:physiology; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*
chemical_list: D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface; D007375:Interleukin-1; D007376:Interleukin-2; D055646:Killer Factors, Yeast; D011506:Proteins; D007371:Interferon-gamma