TNF and depressive disorder: Concerning the results of the present study, when evaluating the cytokine levels considering the patients presenting the association of both clinical situations, i.e., infection by T. gondii and depressive disorder (Group I), compared with all remaining groups of patients (Groups II, III and IV), it was found that the mean level of MIF for these patients was the lowest one, complemented by higher levels of IL-10, TNF, and IL-6 but lower levels of IL-8.