Abstract
In previous studies we have shown that neonates who develop Group B streptococcal sepsis usually lack opsonins to their infecting strain. This investigation was designed to determine the role of antibody and complement in opsonization of these organisms. We also evaluated the effects of fresh blood transfusions on serum opsonic activity in neonates. Group B streptococcal opsonins were determined by a chemiluminescence procedure previously described (JCI 58:1379, 1976). Opsonic activity for types Ia and II was significantly depressed by heating and by inactivation of the classical pathway with Mg++ EGTA. Similar treatment of fresh serum containing type III antibody did not alter opsonic activity for this strain. In the absence of heat stable antibody, fresh serum demonstrated no alternative pathway opsonic activity for group B streptococcal strains; factor B was not activated by electrophoretic analysis; and C3 was not deposited on the cell surface. Comparison of pre and post transfusion sera from 19 neonates showed a rise in opsonic activity only when heat stable antibody was present in donor serum. These results confirm the importance of heat stable antibody and the classical pathway in opsonization of Group B streptococci but do not indicate a major role for the alternative pathway. Therapy aimed at supplying passive immunity to infected neonates will require the presence of heat stable opsonins.
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Shigeoka, A., Hall, R., Hemming, V. et al. ROLE OF ANTIBODY AND THE CLASSICAL AND ALTERNATIVE COMPLEMENT PATHWAYS ON THE OPSONIZATION OF GROUP B STREPTOCOCCI. Pediatr Res 11, 505 (1977). https://doi.org/10.1203/00006450-197704000-00812
Issue Date:
DOI: https://doi.org/10.1203/00006450-197704000-00812