Lymphocyte function in human bone marrow. II. Characterization of an interleukin 2-sensitive T precursor-cell population

Hans Michael Dosch, Cynthia J. Ledgley, Daniel White, Philip Lam, Gordon B. Mills

    Research output: Contribution to journalArticle

    9 Scopus citations


    In the present study of human bone marrow lymphocytes, we analyze a newly recognized population of T suppressor-cell precursors which are found in marrow only and which have the potential to inhibit immunoglobulin (Ig) production in vitro. Following exposure to interleukin 2 (IL2), suppressor precursors acquire E receptor, T3 determinants, suppressor function, and lectin responsiveness. To distinguish this population within the framework of T-cell ontogeny, it was compared to a previously described population of thymus-dependent helper T-cell precursors which express helper function following exposure to thymus-derived mediators. The two populations are completely distinct and can be separated on density gradients. Suppressor precursors expressed T8 and TAC (IL2-receptor) antigens prior to in vitro induction with IL2. The thymic hormone-dependent cells expressed T4 but not T8 or TAC determinants. In two patients with severe combined immunodeficiency disease (SCID), IL2-responsive precursor cells appeared only late after thymus epithelium transplantation, perhaps best explained by a model in which thymus-dependent differentiation pathways precede, induce, or seed pathways of extrathymic T-cell differentiation. The large pool size of over 1011 suppressor and helper precursor cells present in adult bone marrow suggests that these populations may play an important role in immune homeostasis.

    Original languageEnglish (US)
    Pages (from-to)345-356
    Number of pages12
    JournalJournal of Clinical Immunology
    Issue number5
    StatePublished - Sep 1 1985



    • T-cell ontogeny
    • interleukin 2 (IL2)
    • severe combined immunodeficiency disease (SCID)
    • suppressor/helper cells
    • thymic hormone

    ASJC Scopus subject areas

    • Immunology and Allergy
    • Immunology

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