Reactivity of IgE in humanSchistosoma mansoni sera toS. mansoni antigens

Abstract

Sera from Schistosoma mansoni-infected human patients were tested for total IgE levels and specific IgE and IgG antibodies to S. mansoni adult worm, cercaria, and egg antigen by ELISA. Of 50 sera, 28 were investigated by enzyme-linked crossed immunoelectrophoresis (ELCIE) to detect IgE reactivity to individual adult worm extract components. All sera showed increased total IgE levels. Specific IgE antibody levels to the different antigens varied; they were significantly correlated with each other but independent from total IgE. No correlation was found between specific IgG and any of the IgE antibody levels. Testing of the 28 individual sera by ELCIE revealed heterogeneous patterns. Seven sera were found to be nonreactive: three reacted with one precipitate, and the others reacted with between two and nine precipitates. However, in no case were identical patterns recognized, although four antigens reacted with about 80% of the sera. The number of bands detected by the individual sera depended neither on the levels of total IgE nor on those of specific IgE.

Differential responsiveness of humans with early-stage schistosomiasis haematobium to Schistosoma haematobium soluble adult-worm and egg antigens

“…The most striking observation was that signi®cantly more SAWA than SEA bands bound antibodies. This ®nding is in accord with the well-established conservation of B-cell epitopes between the dierent life-cycle stages of the parasite (Shah and Ramaswamy 1982;Payares et al 1985;Weiss and Strand 1985;Dalton et al 1986) and has previously been recorded in murine (Dalton et al 1986) and human (Reiner and Zahner 1989) studies. It may be assumed that it is the highly immunogenic SEA and not the poorly immunogenic SAWA that are responsible for inducing IgG antibody production during early-stage infections, in accordance with the numerous studies that have demonstrated that anti-schistosome antibody production rises in laboratory animals in a highly signi®cant manner with the onset of egg laying (Oberlin and Weiss 1977;Suzuki and Damian 1981;Weiss and Strand 1985).…”

“…These data again suggest that SEA is more immunogenic than SAWA in humans with earlystage schistosomiasis. Testing of the individual sera with SAWA and SEA immunoblots revealed heterogeneous patterns as previously observed repeatedly (Roberts et al 1987;Reiner and Zahner 1989;Al-Sherbiny et al 1995). The most striking observation was that signi®cantly more SAWA than SEA bands bound antibodies.…”