Macrophage functions during dengue virus infection: antigenic stimulation of B cells.

This study was undertaken to investigate the function of dengue type 2 virus (DV)-infected mouse peritoneal macrophages (M phi) regarding the antigenic stimulation of B lymphocytes of the spleen. It was observed that a variable proportion of M luminal diameter show DV-specific immunofluorescent antigen, which depended upon the route of administration of the virus, being higher in i.p.-inoculated mice and in vitro-infected M luminal diameter monolayers. The DV-infected M luminal diameter presented the DV antigen to B cells in vitro and in vivo, leading to their clonal expansion as shown by counting the virus-specific IgM antibody plaque-forming cells (PFC). The PFC response depended upon the number of DV-infected M luminal diameter. The antigen was presented equally well both by I-A-negative and I-A-positive M luminal diameter. Superimposition of a heterologous antigen (Coxsackie B4 virus) in a Mackaness type of experiment depressed the capacity of M luminal diameter to present both the homologous as well as heterologous antigen.