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. 1969 Aug;63(4):1151-6.
doi: 10.1073/pnas.63.4.1151.

Natural immunity to bacterial infections: the relation of complement to heat-labile opsonins

M R Smith, H S Shin, W B Wood Jr

Natural immunity to bacterial infections: the relation of complement to heat-labile opsonins

M R Smith et al. Proc Natl Acad Sci U S A. 1969 Aug.

Abstract

Heat-labile opsonins to pneumococci in normal mammalian sera, unlike antibodies, fail to interact with the bacteria at 0 degrees C and require Ca(++) and/or Mg(++). They are readily removed from serum by antigen-antibody complexes that fix complement (C) and are inhibited by reagents that inactivate various C components. The principal heat-labile opsonin to pneumococci is activated C3 (C3(b)), but a slight enhancing effect is exerted by one or more of the late-reacting components of the hemolytic complement system (C5-C9). Since heat-labile opsonins are immunologically polyspecific, they presumably play a broad protective role in the early (preantibody) phase of acute bacterial infections.

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References

    1. Immunology. 1965 Jun;8(6):590-603 - PubMed
    1. Immunochemistry. 1966 Mar;3(2):111-35 - PubMed
    1. Biochemistry. 1968 Aug;7(8):2991-6 - PubMed
    1. J Exp Med. 1968 Nov 1;128(5):991-1009 - PubMed
    1. Science. 1968 Dec 13;162(3859):1281-3 - PubMed

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