Human IgE, IgG Subclass, and IgM Responses to Worm and Egg Antigens in Schistosomiasis Haematobium: A 12‐Month Study of Reinfection in Cameroonian Children

Abstract

Levels of IgE, IgM, and IgG subclasses against Schistosoma haematobium adult worm antigen (AWA) and soluble egg antigen (SEA) in a cohort of 148 S. haematobium-infected schoolchildren were determined before and up to 12 months after chemotherapy. Infection intensities were determined as concentrations of circulating anodic antigen (CAA) in serum. One month posttreatment, the antibody levels of all isotypes against AWA were increased, but 1 year after treatment they returned to pretreatment levels. CAA concentrations were positively associated with levels of IgG4 against AWA and SEA but not with levels of IgE. Age correlated negatively with CAA concentrations and positively with levels of IgE to AWA. The balance of anti-AWA IgG4 and IgE was significantly correlated to the CAA concentration, in particular in the older age group (11-13 years). This may suggest that protective immune mechanisms in S. haematobium infections become effective around the age of 12 years.

Association of In Utero Sensitization to Schistosoma haematobium with Enhanced Cord Blood IgE and Increased Frequencies of CD5– B Cells in African Newborns

“…3,4,6,7,19 The intravascular location of schistosomes ensures that antigens excreted or secreted by worms and eggs directly enter the maternal vasculature. 14,26,37 These antigens may thus reach the placenta and the fetal vessels. 14,15,19,25,38 For the schistosome antigen CAA, it has already been shown in an animal model that it can be transferred to the offspring via the placenta.…”

“…24 Circulating anodic antigen is a gutassociated, species-unspecific proteoglycan, produced in relatively large quantities by the parasite that can be detected in plasma. [25][26][27] Of the participants, 23 women provided fecal samples, which were prepared with standard methods for microscopic examination to determine the presence of intestinal helminth infections. Microbiologic examination of the mothers was only performed at the time of delivery.…”

The effect of treatment on the age-antibody relationship in children infected with Schistosoma mansoni and Schistosoma haematobium

“…IgA levels have been shown to either remain unchanged in the case of S. mansoni infections (Gryzchl et al 1993) or decrease for S. haematobium infections following treatment (Mutapi et al 1998a/b). IgG1 and IgM responses have been shown to increase in S. haematobium infections (Mutapi et al 1998a, Naus et al 1998). IgG2 and IgG4 responses have been shown to both increase and decrease for S. haematobium infections , Mutapi et al 1998a, Naus et al 1998).…”

“…IgG1 and IgM responses have been shown to increase in S. haematobium infections (Mutapi et al 1998a, Naus et al 1998). IgG2 and IgG4 responses have been shown to both increase and decrease for S. haematobium infections , Mutapi et al 1998a, Naus et al 1998). The causes of such heterogeneity in the treatment-induced changes in humoral responses include both host and parasite related factors (Mutapi 2001).…”

Urinary schistosomiasis

“…Apart from lower exposure in adults, the capacity to resist new infection by eosinophil secretion of antigen-specific immunoglobulin E (IgE) is age dependent [5]. Children younger than 13 years have a higher serum level of IgM, IgG2 and IgG4 isotypes which block the protective effect of IgE [6].…”