ANTIGENIC-COMPETITION BETWEEN DENGUE AND COXSACKIE-VIRUSES FOR PRESENTATION TO B-CELLS BY MACROPHAGES

  • 1 December 1990
    • journal article
    • research article
    • Vol. 71  (6) , 761-770
Abstract
Macrophages (M.vphi.) pulsed with dengue type 2 (DV) and Coxsackie B4 (CoxB) viruses present antigen to B lymphocytes leading to their clonal expansion as detected by counting antigen-specific IgM antibody plaque-forming cells (PFC). The present study was undertaken to investigated the site for competition in M.vphi. between the two heterologous antigens. DV and CoxB, for their presentation of B cells. It was observed that DV-pulsed M.vphi. presented antigen to B cells in mice depleted of T cells by treatment with anti-Thy I.2 monoclonal antibodies. The B cells could not be stimulated in absence of M.vphi. in mice treated with silica. The PFC counts for both the antigens were inhibited when M.vphi. were pulsed simultaneously with DV and CoxB. PFC counts were increased by 53-I20% by predigesting the antigens by trypsin. Inhibition of DV-specific response by CoxB was abrogated by predigesting CoxB. A marked reduction in DV-specific PFC response was observed when CoxB was superimposed on M.vphi. pulsed with DV 24 h earlier. CoxB-specific PFC counts were not affected by superimposing DV on M.vphi. pulsed with CoxB 24 h earlier. PFC response to the antigen given to M.vphi. before glutaraldehyde fixation was not affected while that for the antigen given to glutaraldehyde-fixed M.vphi. was markedly depressed. It is concluded that the competition between DV and CoxB for antigen presentation to B cells occurs in M.vphi. at the level of antigen processing.