April 1985

Maternal-Fetal Transfer of Pneumococcal Capsular Polysaccharide Antibodies

Author Affiliations

From the Department of Immunology/Microbiology, Rush Medical College, Chicago (Dr Chudwin and Ms Artrip); the Department of Pediatrics, University of California, San Francisco (Drs Wara and Ammann); and the Department of Microbiology/Immunology, Downstate Medical Center, Brooklyn, NY (Dr Schiffman).

Am J Dis Child. 1985;139(4):378-380. doi:10.1001/archpedi.1985.02140060060029

• Maternal-fetal transfer of IgG antibodies is an important host defense for newborns, who have an increased incidence of bacterial infections. To study the transfer of specific pneumococcal capsular polysaccharide (PPS) antibodies, we measured the concentrations, in 30 paired maternal and cord serum samples, of IgG and IgM by radial immunodiffusion, of serotype 7F Streptococcus pneumoniae PPS antibodies by radioimmunoassay and enzyme immunoassay, and of opsonic activity to that organism by a radiolabeled bacterial uptake assay. Cord serum had significantly greater total IgG, yet significantly less type 7F PPS IgG antibodies and opsonic activity than maternal serum. Cord serum had low concentrations of total IgM and no IgM type 7F–specific antibodies. Reduced transport of specific IgG antibodies and absent transfer of IgM may contribute to the susceptibility of newborns to bacterial infection.

(AJDC 1985;139:378-380)