Date of Award


Degree Type


University or Center

Atlanta University (AU)

Degree Name




First Advisor

Dr. Judith Rae Lumb

Second Advisor

Dr. Louise Miller-Stevens


The effect of a latent infection, and an acute infection of Toxoplasma gondii on a metastasizing tumor, was studied in C57BL/6J mice. The metastasizing tumor employed was B16 melanoma (F1 subline). B16 melanoma cells were intravenously injected into mice immediately, and seven days after an intraperitoneal injection of 104 trophozoites of Toxoplasma gondii. A latent infection of Toxoplasma gondii was established in C57BL/6J mice using sulfadiazine. Two weeks after the termination of sulfadiazine, B16 melanoma cells were injected intravenously; two concentrations of B16 melanoma cells were employed throughout the study. All mice were sacrificed twenty-one days following B16 melanoma injections. The lung of each mouse was removed and examined for pulmonary metastases. An acute infection of Toxoplasma gondii was shown to have an enhancing effect on B16 melanoma cells; where as a latent infection was shown to inhibit proliferation of the tumor. The results of this study indicate that whether Toxoplasma gondii has an inhibitory or an enhancing effect on B16 melanoma cells depends on the activity status of the immune system.

Included in

Biology Commons