These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Antigen-independent activation of cytotoxic T cells by lymphokines.
    Author: Williams LD, McMaster WR, Teh HS.
    Journal: Immunology; 1988 May; 64(1):121-8. PubMed ID: 3133307.
    Abstract:
    Supernatants from phorbol myristate acetate (PMA)-stimulated EL4.IL2 cells (EL4.PMA), but not recombinant IL-2 (rIL-2), induced the production of cytotoxic T lymphocytes (CTL) in low density murine spleen cell cultures. CTL induction in these cultures was completely abrogated by treatment with anti-Thy-1 or anti-Lyt-2 antibody plus complement but not by anti-L3T4 antibody plus complement. Fractionation of EL4.PMA on a Sephadex G-150 column demonstrated that the CTL-inducing activity in EL4.PMA eluted with an apparent molecular weight of about 44,000 and was partially separated from IL-2. This 44,000 MW material was shown to contain insignificant amounts of PMA. Following a 3-day culture period with the partially purified factor, C57BL/6J thymocytes could proliferate and differentiate into cytotoxic cells in response to rIL-2, whereas there was no proliferation or generation of cytotoxic cells when the thymocytes were cultured in rIL-2 alone. The number of IL-2 receptor-positive cells in C57BL/6J thymocytes also increased from 1.1% to 22.8% after 3 days of culture in the partially purified factor. Recombinant IL-4 (BSF-1) and IL-5 (TRF), when used alone or in combination with rIL-2, were unable to induce a cytotoxic response under similar culture conditions. These findings are consistent with the interpretation that EL4.PMA contains a novel lymphokine that directly, or indirectly, induces the expression of IL-2 receptors on resting CTL precursors without intentional stimulation by specific antigen. In the presence of IL-2, these precursors may then differentiate into effector CTL.
    [Abstract] [Full Text] [Related] [New Search]