title: Effects of interferon and radiation dose on the suppressive activity of human lymphocytes primed with allogeneic cells in mixed lymphocyte cultures.
abstract: Peripheral blood lymphocytes (PBL) primed in vitro with irradiated allogeneic PBL can suppress alloactivated proliferation of fresh autologous PBL in a primary mixed lymphocyte culture (MLC). Proliferation of fresh PBL was measured by tritiated thymidine uptake after 6 days of coculture with irradiated fresh allogeneic stimulator PBL; irradiated autologous primed PBL were added to assess suppression. These primed cells had been cultured for 6 to 10 days prior to their irradiation and addition to a primary MLC. Suppression in this assay by PBL primed for 6 days was inversely correlated with radiation dose. The addition of highly purified recombinant interferon-alpha (IFN) during the 6-day priming of these lymphocytes did not alter their suppressive ability, nor did it alter the radiation sensitivity of their suppression. In contrast, PBL primed for 10 days were highly suppressive even if irradiated before their addition to the assay. However, when PBL were primed for 10 days in the presence of IFN, their ability to suppress was again radiation sensitive. These data suggest that between days 6 and 10 of primary MLC, IFN inhibits either proliferation or differentiation of a lymphocyte population involved in the generation of radioresistant suppressive activity.
authors.forename: P
authors.initials: P
authors.lastname: Aebersold
authors.forename: B
authors.initials: B
authors.lastname: Chen
authors.forename: P M
authors.initials: PM
authors.lastname: Sondel
mesh_terms: D002478:Cells, Cultured; D004306:Dose-Response Relationship, Immunologic; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D007108:Immune Tolerance / Q000528:radiation effects*; D007370:Interferon Type I / Q000276:immunology*; D007959:Lymphocyte Culture Test, Mixed; D008214:Lymphocytes / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects* / Q000528:radiation effects; D013997:Time Factors
chemical_list: D007370:Interferon Type I