title: Oral immunization of mice against Schistosoma mansoni using drinking water from trays containing Biomphalaria alexandrina infected with Schistosoma mansoni.
abstract: Water collected from trays containing Biomphalaria alexandrina infected with Schistosoma mansoni at the time of cercariae shedding (SmISW) and trays containing clean, non-infected, B. alexandrina (NISW) and underground water (UW), were filtered used as a drinking water for 3 groups of albino mice males. After two months, blood samples were collected from the 3 groups and serum was tested for anti-cercarial IgG, then mice were infected with 150 S. mansoni cercariae. Eight weeks after infection, mice were perfused and adult S. mansoni worms were counted. Anti-cercarial IgG was positive in 23 (82.1%) out of the 28 samples collected from mice drinking SmISW and only in 2 (9.5%) out of the 21 samples collected from mice drinking NISW, while all samples collected from mice drinking UW were negative for anti-cercarial IgG (X2=45.897; P<0.001). Worm load was significantly lower in the group of mice drinking SmISW than mice drinking NISW (P=0.032) and mice drinking UW (P=0.02). In mice drinking SmISW, adult worm count showed significant negative correlation with anti-cercarial IgG concentration (Kendall's taub =-0.325 and P=0.018). The results indicate that antigens present in drinking water stimulate a level of immunity against schistosomiasis, (inhabitants of endemic areas) resulting in a lower intensity and severity of infection. Also, it may reduce the specificity of serological tests used for diagnosis of Schistosoma infection, based on antibody determination.
authors.affiliation: Department of Parasitology, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
authors.forename: M S
authors.initials: MS
authors.lastname: Noureldin
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000947:Antigens, Helminth / Q000276:immunology; D001700:Biomphalaria / Q000469:parasitology*; D004199:Disease Vectors; D006790:Host-Parasite Interactions; D007114:Immunization; D008297:Male; D051379:Mice; D012550:Schistosoma mansoni / Q000254:growth & development / Q000276:immunology*; D012555:Schistosomiasis mansoni / Q000517:prevention & control*; D014612:Vaccines / Q000008:administration & dosage* / Q000276:immunology; D014867:Water / Q000008:administration & dosage* / Q000469:parasitology*
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D014612:Vaccines; D014867:Water