Regulation of human cytotoxic T lymphocyte development by IL-7

• Published in: The Journal of immunology (1950) Vol. 145; no. 8; pp. 2415 - 2420
• Main Authors: Hickman, CJ, Crim, JA, Mostowski, HS, Siegel, JP
• Format: Journal Article
• Language: English
• Published: United States Am Assoc Immnol 15.10.1990
• Subjects: Antigens, Differentiation, T-Lymphocyte - analysis; CD8 Antigens; Concanavalin A - pharmacology; Cytotoxicity, Immunologic - drug effects; Dose-Response Relationship, Drug; Esterases - metabolism; Humans; Immunity, Cellular; Immunologic Memory; In Vitro Techniques; Influenza A virus - immunology; Interleukin-7 - pharmacology; Interleukin-7 - physiology; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; T-Lymphocytes, Cytotoxic - physiology; Time Factors
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.145.8.2415

The effects of IL-7 on the generation of human CTL in alloantigen-, virus-, and lectin-stimulated systems were examined. Addition of IL-7 at the onset of cultures resulted in marked (up to 80-fold) augmentation of cytotoxicity accompanied by smaller (1.5- to 4-fold) increases in total lymphocyte number. Studies of CTL development in purified lectin-stimulated CD8+ T cell populations demonstrated that IL-7 could act directly on the CD8+ lymphocyte subset to augment cytotoxicity. In MLC, the IL-7-induced enhancement of cytotoxicity was found to be mediated primarily by the CD8+ subpopulation of lymphocytes. Late addition of IL-7 (day 5 of 7) resulted in an increase in cytolytic activity that was associated with little or no increase in total or activated CD8+ lymphocyte number indicating that IL-7 may act as a differentiation factor for human CTL. A role for endogenous IL-7 in CTL development was suggested by the observation that addition of neutralizing antiserum to IL-7 to MLC at initiation (or 5 days thereafter) resulted in decreased levels of cytotoxicity. These results indicate that IL-7 can exert major up-regulatory effects on human CTL development and suggest that these effects are both proliferative and differentiative.