Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1976 May 1;143(5):1186-98.
doi: 10.1084/jem.143.5.1186.

Immunity to the group B streptococci: interaction of serum and macrophages with types Ia, Ib, and Ic

Immunity to the group B streptococci: interaction of serum and macrophages with types Ia, Ib, and Ic

B F Anthony. J Exp Med. .

Abstract

The opsonization and phagocytosis of group B streptococci of types Ia, Ib, and Ic were studied in vitro by measuring the uptake of radioactivity by coverslip cultures of rabbit alevolar macrophages during incubation with radiolabeled, nonviable bacteria which had been exposed to rabbit serum. The uptake of counts per minute was quantitative, reproducible, and reversibly inhibited by cold, indicating that it was largely a measurement of phagocytic ingestion rather than of attachment of bacteria-immunoglobulin complexes to macrophage membranes. Moreover, suspended macrophages killed approximately 90% of viable streptococci in the presence of specific antiserum. The opsonic activity of immune serum was heat stable, and phagocytosis of streptococci was insignificant after incubation with normal serum and antiserum to some heterologous group B streptococci. By absorption studies, it was possible to identify the effect of antibodies to specific bacterial antigens. Phagocytosis of streptococci containing the corresponding antigens was maximal after opsonization with homologous or heterologous sera containing antibody to IaCHO, IbCHO, or Ibc protein. Phagocytosis of all three serotypes was intermediate when opsonization could be attributed to anti-IabcCHO. The opsonization of a specific group B streptococcus is complex and may involve two or more antigen-antibody systems.

PubMed Disclaimer

References

    1. Infect Immun. 1976 Jan;13(1):284-8 - PubMed
    1. Infect Immun. 1975 Apr;11(4):845-52 - PubMed
    1. J Exp Med. 1975 Jul 1;142(1):165-79 - PubMed
    1. J Immunol. 1973 Aug;111(2):369-80 - PubMed
    1. J Pediatr. 1973 Dec;83(6):926-32 - PubMed