Application of adult worm and lung-stage antigens to immunize against schistosoma mansoni using cytokines as adjuvants

ABSTRACT

Different Schistosoma mansoni antigens; adult worm antigen [SWAP] and lung-stage antigen [SLAP] together with different cytokine adjuvants [Interferon-gamma and Interleukin-4] were used to immunize mice against. S. mansoni. Immunization program was directed towards the production of an intense immune response together with balanced T-helper1 and T-helper2 immune responses. The goal of immunization was not only to protect from infection but also to modulate the pathology inflicted by the parasite. Parameters like adult load, egg counts, anti-Schistosoma antibody titers and liver pathology were used to evaluate the different immunization scheme. SLAP antigen has proven to be a better antigen not only in protection but also in pathology modulation. SLAP plus IFN-gamma as an adjuvant was the best immunization regimen with almost 50% protection and a remarkable resolving of parasite pathology. Unexpectedly, IL- 4 had a weak but observed adjuvant protective effect. The results is a step in the path for a Schistosoma vaccine that guides the immune system towards a balanced response targeting the pathology induced by the parasite rather than the parasite itself