IMMUNE SUPPRESSION WITH SUPRAOPTIMAL DOSES OF ANTIGEN IN CONTACT SENSITIVITY .1. DEMONSTRATION OF SUPPRESSOR CELLS AND THEIR SENSITIVITY TO CYCLOPHOSPHAMIDE

  • 1 January 1977
    • journal article
    • research article
    • Vol. 119  (1) , 240-244
Abstract
Immunologic suppression was induced in a mouse model of contact sensitization to DNFB [dinitrofluorobenzene] by using supraoptimal doses of antigen. In these studies, in vivo measurement of ear swelling as an indication of immunologic responsiveness correlated well with measurement of in vitro antigen-induced cell proliferation. This unresponsiveness was specific, since supraoptimal doses of DNFB did not interfere with the development of contact sensitivity to another contactant, oxazolone. The decrease in responsiveness is a form of active suppression, as lymphoid cells from supraoptimally sensitized donors transferred suppression to normal recipients. Pretreatment with cyclophosphamide (Cy) reversed the suppression seen in supraoptimally sensitized animals but had no effect on the optimal sensitization regimen. Supraoptimal doses of contactants can apparently activate suppressor cells, and precursors of these cells are apparently sensitive to Cy. Such suppressors regenerate within 7-14 days after Cy treatment. The ability of Cy pretreatment to affect supraoptimal sensitization without affecting optimal sensitization shows that the observed results of Cy treatment depend critically upon the dose of antigen used.