The Immunobiology of Urogenital Schistosomiasis

Schistosoma haematobium, the infectious agent responsible for urogenital schistosomiasis, infects over 112 million people annually in Sub-Saharan Africa alone. Despite a complicated life-cycle within the human host, the vast majority of clinical manifestations occur in response to eggs deposited into the bladder and ureter walls by adult worms. Egg-associated inflammatory lesions feature markedly dysregulated fibrosis responsible for obstructive disease, and urothelial alterations linked to human bladder cancers. Epidemiologic evidence suggests that S. haematobium is responsible for 32 million cases of dysuria, 10 million cases of hydronephrosis, and 150,000 deaths from renal failure annually, making S. haematobium the world’s deadliest schistosome. Despite the fundamental role of urogenital pathology in human disease, few animal models have been able to recreate natural infection. This review gathers the existing body of knowledge regarding the immunological events during S. haematobium infection, and surveys novel S. haematobium infection models to reflect on how we can move forward towards understanding both the pathologic and protective immune responses to the world’s deadliest schistosome.

Keywords: Bladder, cancer, co-infection, eosinophils, fibrosis, granuloma, haematobium, immunity, Immunoglobulin-E, Immunoglobulin-G4, immunemodulatory, immunopathology, injection, innate, Interleukin-10, Interleukin-5, Schistosoma, schistosomiasis, urogenital, urothelial.