Transfer by serum and cells of resistance to infection with Strongyloides ratti in mice.

C57Bl/6 mice were infected with Strongyloides ratti. Susceptibility to infection was ascertained by quantifying the numbers of larvae in the faeces 1 week after infection. Resistance to infection was transferred by pooled immune serum and mesenteric lymph node (MLN) cells obtained 2 and 3 weeks after infection. There was no additive effect when immune serum and MLN cells were given together. Protection was not conferred by MLN cells 1, 4 or 6 weeks after infection nor by spleen cells taken 1--6 weeks after infection. There was, however, a mild non-specific reduction in larval excretion after transfer of either normal or immune spleen cells. These data indicate that both humoral and cell-mediated immune responses may confer resistance to infection in murine strongyloidiasis.