Abstract
An in vitro study was carried out on cell-mediated immunity in mice experimentally infected with Toxoplasma gondii to estimate the ability of antigenically stimulated lymphocytes. Lymphocytes were collected from immune and non-immune mouse spleens and incubated in the presence or absence of specific Toxoplasma antigen. When normal macrophages were cultured in the culture supernatant from immune lymphocytes incubated with Toxoplasma lysate antigen and infected with Toxoplasma, the intracellular multiplication of the parasite was inhibited remarkably. On the contrary, there was a progressive increase in infected macrophages cultured in the supernatant from immune lymphocytes incubated without antigen, or in the supernatant from normal lymphocytes incubated with antigen. These results suggest that resistance to and microbicidal activity upon Toxoplasma parasites may have been conferred to macrophages by the culture supernatant from immune lymphocytes reacting with Toxoplasma antigen.
