T-cell immunity in human chronic toxoplasmosis.

Toxoplasmosis is a disease affecting 500 million people worldwide. The seroprevalence varies (from 5% to 90%), depending on geographical location, age, habit of eating raw meat or unwashed fruit and vegetables, and general level of hygiene. The incidence of infections is higher in warmer and humid climate and increases with age. The disease can be congenital or acquired. Cell response (TNF-alpha and IFN-gamma secreted by Th1 cells) and humoral response (IL-4, and IL-10 secreted by Th2 cells) were evaluated. This study assessed the effect of T. gondii on chosen indices of the immune response. The study involved 45 women infected with T. gondii (aged 18-42 years) proven have a chronic toxoplasmosis (IgG positive & IgM negative). The control group consisted of 25 healthy women (aged 18-45 years) (IgG and IgM negative). The results showed that patients infected with T. gondii had increased production of theTh-1 cytokines involved TNF-alpha and IFN-gamma that responsible for the cellular response compared to controls. Also, increased production of Th2 cytokines involved IL-4 and IL-10 that responsible for humoral response compared to controls.