Immunofluorescence studies of schistosome structures which share determinants with circulating schistosome antigens

An attempt was made to demonstrate by immunofluorescence the presence and location of antigens sharing determinants with circulating schistosomal antigens (CSA) (BAWDEN & WELLER, 1974; NASH et al., 1974) in several developmental stages of Schistosoma mansoni. We also studied the immunoglobulin (Ig) class of antibodies in patients’ serum that attach to sites where CSA determinants are found. Both cryostat sections of material frozen in liquid nitrogen (196°C) and Bouin-fixed paraffinembedded sections were used. Material consisted of cercariae, skin-penetrating schistosomula, fiveday migrating schistosomula, adult worms and eggs of S. mansoni. The location of CSA determinants in the schistosomal preparations was detected by indirect immunofluorescence, using specific antiserum to CSA (NASH et al., 1974) and fluoresceinconjugated goat anti-rabbit globulin (Hyland Laboratories, Los Angeles, Cal., U.S.A.).