title: Agar human T cell colony growth promoted by a B + null cell-derived lymphokine distinct from IL 2.
abstract: Human T cell agar colonies can be grown under PHA stimulation from either mature T cells or their E rosette-negative (E-), OKT3- peripheral blood and bone marrow precursors. Colonies comprise a majority of mature E+, OKT3+ cells and a minor (5 to 10%) population of immature E-, T3-, T8-, T4-, DR+, T10+, RFB1+ cells, which upon replating in subculture, can generate secondary colonies of OKT3+, E+, OKT4+, OKT8+ cells. Secondary colony formation can serve as a test for growth requirement of colony precursors, because it depends on the presence of both PHA and a colony-promoting activity (CPA) recovered in PHA-stimulated B + null or T + adherent cell supernatants. CPA production by B + null cells was not affected by their treatment with OKT3 or D66 (T11-like) monoclonal antibodies (MAB) + complement but was abolished by an anti-HLA-DR MAB + complement. However, B cells sorted by panning with the same anti-HLA-DR MAB did not release CPA, demonstrating the requirement of both B cells and null cells for CPA production. Neither IL 2 nor IL 1 could account for B + null cell-derived CPA.
mesh_terms: D001402:B-Lymphocytes / Q000378:metabolism*; D002454:Cell Differentiation; D003115:Colony-Stimulating Factors / Q000096:biosynthesis / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis / Q000502:physiology*; D008213:Lymphocyte Activation; D008215:Lymphocytes, Null / Q000378:metabolism*; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology
chemical_list: D003115:Colony-Stimulating Factors; D007375:Interleukin-1; D007376:Interleukin-2