Studies on the role of tumor necrosis factor- alpha (TNF-α) in hepatocytes induced apoptosis in vaccinated, Schistosoma mansoni-challenged mice.

Tumour Necrosis Factor-alpha (TNF-α) plays a complex role in pathophysiological changes caused by schistosomiasis in the liver cells as induced apoptosis. So, The highlighted experimentally the role of TNF-α in hepatocytes apoptosis, using that as an assessment of the efficacy of antischistosomal vaccination by mixed crude antigens preparations [Cercarial antigen preparation (CAP) + soluble worm antigen preparation (SWAP) + soluble egg antigen(SEA)] by parasitological, histo-pathological and histochemical studies using Feulgen stain of hepatoytes DNA, a serological study also of serum TNF-α level by ELISA. Fifty two laboratory bred Albino male mice, were used in this study. They were classified into four groups (13 mice in each group), G1: normal control, G2 as infected control while G3 supported by Freund's Adjuvant (F. Adj) then infected and G4 vaccinated with combined antigens (CAP, SWAP and SEA) + F. Adj, then infected. Mice were sacrificed by cervical dislocation 9 weeks post infection, parasitological (Kato-Katz thick smear for egg count), histopathologial {haematoxylin and eosin (H&E) staining of hepatic sections}, histochemical (feulgen staining of hepatocytes DNA) and ELISA to estimate serum TNF-α level were performed. The data showed that vaccination with combined antigens showed protective effect on vaccinated then Schistosoma challenged mice, hepatocytes induced apoptosis was directly proportional with the TNF-α serum level, and the protection degree of potential combined vaccine was inversely proportional with serum TNF-α level and induced apoptosis.