EFFECT OF SEX-HORMONES ON THE IMMUNE SYSTEM OF GUINEA-PIGS AND ON THE DEVELOPMENT OF TOXOPLASMIC LESIONS IN NON-LYMPHOID ORGANS

  • 1 January 1979
    • journal article
    • research article
    • Vol. 36  (1) , 16-23
Abstract
The role of cell-mediated immunity in the pathogenesis of toxoplasmic lesions in non-lymphoid organs and its significance in resistance to infection with Toxoplasma gondii were studied in guinea pigs. Alteration of the sex hormonal environment in both sexes has significant effects on the immunological status of the guinea pig, changing its reaction to toxoplasmic infection. Gonadectomy appears to enhance delayed hypersensitivity, leading to a greater prominence of lesions in the non-lymphoid organs of gonadectomized male and female animals than in controls. Delayed hypersensitivity might play a major role in the pathogenesis of non-lymphoid, toxoplasmic lesions. Hexestrol administration for a long period of time induces complete thymic atrophy and severe involution of the thymus-dependent areas of the lymph nodes and spleen, leading to the suppression of cell-mediated immunity and overwhelming disease in those animals infected with T. gondii, suggesting that cell-mediated immunity is of importance in resistance to toxoplasmic infection. The difficulties in the treatment of non-lymphoid toxoplasmic lesions, such as ocular ones, by depressing cellular immunity are discussed.