Antibodies against Entamoeba histolytica in individuals with intestinal amoebiasis presenting cysts and/or trophozoites in the feces.

Serum samples were obtained from 154 individuals infected with Entamoeba histolytica (78 symptomatic and 76 asymptomatic). Twelve had trophozoites in the feces whereas 142 had only cysts. The sera were used to test the existence of antibodies anti-Entamoeba histolytica employing the Indirect Hemagglutination (IHA), Indirect Immunofluorescence (IFAT), Complement Fixation Reaction (CFR) and Counterimmunoelectrophoresis (CIEP).

Entamoeba histolytica: antigenic characterization of axenic strains from Brazil.

Trophozoites from cultures of Entamoeba histolytica strains isolated and grown axenically in Brazil (ICB-CSP, ICB-462 and ICB-32) were used for immune sera production and for characterization of their antigens by using electrophoretic and glycoproteic profiles, in parallel with a standard strain isolated and kept under axenic conditions in USA (HK-9). Hyperimmune sera, presenting high antibody titers with homologous and heterologous antigens, were obtained. The four strains in study revealed similar and complex electrophoretic and glycoproteic profiles showing polypeptides with molecular weights ranging from 200 to less than 29 kDa.