Hegazi F, Ayoub
AA, Mannaa WM, Mobdy HR and El-Sheikh N.
Microbiology Department, Faculty of Medicine for Girls, Al Azhar University, Cairo, Egypt
Previous studies in mouse have demonstrated that upregulation of interferon gamma (IFN-g), correlates with protection from Schistosoma mansoni. In this study we investigated thirty children and adolescents (with mean age of 14 ± 0.6 years) who were resistant to reinfection and live in an endemic focus at Monofia Governorate. Peripheral blood mononuclear cells (PBMC) were cultured with soluble egg antigen (SEA) in an in vitro granuloma assay (IVG). After 24 hrs culture, cells were simultaneously assessed for intracellular IFN-g mRNA transcript by in situ hybridization (ISH) and for cell surface expression of ICAM-1, LFA-1 and Mac-1 by immunofluorescence. SEA-stimulated cells showed increased percentage of IFN-g mRNA, and ICAM-1, LFA-1, and Mac-1 producing cells (median: 22%, 22.8%, 25.1%, and 34.4% respectively) as compared to the un-stimulated cells (median: 10%, 9.3%, and 9.9%, and 18.8% respectively). The enhanced expression of IFN-g m RNA showed positive correlation with that of ICAM-1, LFA-1 and Mac-1 (r: 0.77, 0.71 and 0.66 respectively). These findings suggest that IFN-g plays a role in SEA-specific cytokine-mediated upregulation mechanism expression of these adhesion molecules in human schistosomiasis.