MODIFICATION OF LYMPHOCYTE RESPONSIVENESS INVITRO BY CARRAGEENAN COMPARED WITH COLLOIDAL SILICA AND DEPLETION OF SURFACE ADHERENT CELLS

  • 1 January 1978
    • journal article
    • research article
    • Vol. 31  (3) , 426-435
Abstract
The effects of the immunosuppressive sulfated polygalactan .lambda. carrageenan on in vitro models of [pig] allograft immunity were compared with the effects of removing macrophages (surface adherent and/or phagocytic cells) by established methods. Carrageenan depressed primary mixed lymphocyte reactions, but not to the same extent as the removal of macrophages. 2-Mercaptoethanol restored the response. Secondary mixed lymphocyte reactions and responses to phytohemagglutinin were depressed by carrageenan but not by the removal of macrophages; in these systems 2-mercaptoethanol failed to restore the responses of carrageenan-treated cultures. Cell-mediated cytolysis by presensitized lymphocytes was not affected by carrageenan or by colloidal silica. Carrageenan depressed cell-mediated cytolysis only if it was present during the sensitization of the effector cells. Carrageenan can have 2 dose-related effects in vitro: 1 on the macrophage and 1 on the responding lymphocyte.