Humoral Immunity in Arsenic-Exposed Children in Rural Bangladesh: Total Immunoglobulins and Vaccine-Specific Antibodies.

Abstract

Background:Early-life arsenic exposure has been associated with reduced cell-mediated immunity, but little is known about its effects on humoral immunity.Objective:We evaluated whether prenatal and childhood arsenic exposure was associated with humoral immune function in school-aged children.Methods:Children born in a prospective mother–child cohort in rural Bangladesh were immunized with measles, mumps, and rubella (MMR) vaccines at 9 years of age (). Arsenic exposure was assessed in urine (U-As), from mothers during pregnancy and their children at 4.5 and 9 years of age. Total IgG (tIgG), tIgE, tIgA, and MMR-specific IgG concentrations were measured in plasma using immunoassays.Results:Arsenic exposure was positively associated with child tIgG and tIgE, but not tIgA. The association with tIgG was mainly apparent in boys (p for ), in whom each doubling of maternal U-As was related to an increase in tIgG by . The associations of U-As at 9 years with tIgG and tIgE were evident in underweight children (p for interaction ). Childhood arsenic exposure tended to impair mumps-specific vaccine response, although the evaluation was complicated by high preimmunization titers. Postimmunization mumps–specific IgG titers tended to decrease with increasing U-As at 4.5 and 9 years of age [regression coefficient ; 95% confidence interval (CI): , 0.01; and ; 95% CI: , ; , respectively) in 25% children with the lowest preexisting mumps-specific IgG titers.Conclusions:Arsenic exposure increased tIgG and tIgE in plasma, and tended to decrease mumps-specific IgG in children at 9 years of age. https://doi.org/10.1289/EHP318