Transplacental passage of specific antibodies from mother to neonatal infant was demonstrated in Schistosoma mansoni infections in man. This passage of antibody was demonstrated by the circumoval precipitin method, the Ouchterlony double-diffusion method with adult worm and cercarial extracts of S. mansoni, and by the cercarial slide-flocculation method. Immunoglobulin levels between mothers and their infants were compared by simple radial immunodiffusion. Levels of immunoglobulin G of mothers and their infants were similar; however, no immunoglobulin A was detected in the serum from the neonatal infants, and only three of 16 infants had measurable amounts of immunoglobulin M by the methods used. We believe this to be presumptive evidence that the transplacental passage of specific antibodies from mothers to their neonatal infants in S. mansoni infections is due to serum IgG.
Department of Microbiology, The University of Chicago, 939 East 57th Street, Chicago, Illinois 60637. Trainee, United States Public Health Service Training Grant No. AI-00331.