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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1978 Apr;75(4):1989–1993. doi: 10.1073/pnas.75.4.1989

Crossreacting determinants in variant-specific surface antigens of African trypanosomes.

A F Barbet, T C McGuire
PMCID: PMC392468  PMID: 77021

Abstract

A number of variant-specific surface antigens (VSSAs) were purified from clones of Trypanosoma brucei and T. congolense and tested for immunological crossreactivity. Anti-VSSA sera were clone-specific when tested by indirect immunofluorescence of living trypanosomes, but they were not clone-specific when tested by radioimmunoassay with purified 125I-labeled VSSAs. In this double-antibody radioimmunoassay every VSSA tested was precipitated by the homologous and all heterologous anti-VSSA sera. Any unlabeled VSSA could inhibit the heterologous precipitation reactions by 100%. The homologous precipitation reactions were effectively inhibited only by unlabeled homologous VSSA. Crossreactions between different VSSA molecules were also revealed by microcomplement fixation tests. The results confirm the presence, in VSSAs, of variable determinants specific to individual VSSAs and also show crossreacting determinants in all VSSAs tested, including those isolated from different species of trypanosomes. These results contrast with previous studies which failed to find evidence for immunological crossreactivity between different VSSA molecules. We suggest that the crossreacting determinants in VSSAs may represent common structural regions. The existence of such regions would have considerable implication for the development of theories and experiments concerning the mechanism of antigenic variation in African trypanosomes.

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1989

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bridgen P. J., Cross G. A., Bridgen J. N-terminal amino acid sequences of variant-specific surface antigens from Trypanosoma brucei. Nature. 1976 Oct 14;263(5578):613–614. doi: 10.1038/263613a0. [DOI] [PubMed] [Google Scholar]
  2. CUNNINGHAM M. P., VICKERMAN K. Antigenic analysis in the Trypanosoma brucei group, using the agglutination reaction. Trans R Soc Trop Med Hyg. 1962 Jan;56:48–59. doi: 10.1016/0035-9203(62)90088-3. [DOI] [PubMed] [Google Scholar]
  3. Cross G. A. Identification, purification and properties of clone-specific glycoprotein antigens constituting the surface coat of Trypanosoma brucei. Parasitology. 1975 Dec;71(3):393–417. doi: 10.1017/s003118200004717x. [DOI] [PubMed] [Google Scholar]
  4. Cross G. A., Manning J. C. Cultivation of Trypanosoma brucei sspp. in semi-defined and defined media. Parasitology. 1973 Dec;67(3):315–331. doi: 10.1017/s0031182000046540. [DOI] [PubMed] [Google Scholar]
  5. Gray A. R. Antigenic variation in a strain of Trypanosoma brucei transmitted by Glossina morsitans and G. palpalis. J Gen Microbiol. 1965 Nov;41(2):195–214. doi: 10.1099/00221287-41-2-195. [DOI] [PubMed] [Google Scholar]
  6. Kunkel H. G., Agnello V., Joslin F. G., Winchester R. J., Capra J. D. Cross-idiotypic specificity among monoclonal IgM proteins with anti- -globulin activity. J Exp Med. 1973 Feb 1;137(2):331–342. doi: 10.1084/jem.137.2.331. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Lanham S. M. Separation of trypanosomes from the blood of infected rats and mice by anion-exchangers. Nature. 1968 Jun 29;218(5148):1273–1274. doi: 10.1038/2181273a0. [DOI] [PubMed] [Google Scholar]
  8. Rovis L., Barbet A. F., Williams R. O. Characterisation of the surface coat of Trypanosoma congolense. Nature. 1978 Feb 16;271(5646):654–656. doi: 10.1038/271654a0. [DOI] [PubMed] [Google Scholar]
  9. Strand M., August J. T. Structural proteins of mammalian RNA tumor viruses: relatedness of the interspecies antigenic determinants of the major internal protein. J Virol. 1975 Jun;15(6):1332–1341. doi: 10.1128/jvi.15.6.1332-1341.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Vickerman K., Luckins A. G. Localization of variable antigens in the surface coat of Trypanosoma brucei using ferritin conjugated antibody. Nature. 1969 Dec 13;224(5224):1125–1126. doi: 10.1038/2241125a0. [DOI] [PubMed] [Google Scholar]
  11. Vickerman K. On the surface coat and flagellar adhesion in trypanosomes. J Cell Sci. 1969 Jul;5(1):163–193. doi: 10.1242/jcs.5.1.163. [DOI] [PubMed] [Google Scholar]
  12. WASSERMAN E., LEVINE L. Quantitative micro-complement fixation and its use in the study of antigenic structure by specific antigen-antibody inhibition. J Immunol. 1961 Sep;87:290–295. [PubMed] [Google Scholar]
  13. Weber K., Osborn M. The reliability of molecular weight determinations by dodecyl sulfate-polyacrylamide gel electrophoresis. J Biol Chem. 1969 Aug 25;244(16):4406–4412. [PubMed] [Google Scholar]
  14. Wellde B., Lötzsch R., Deindl G., Sadun E., Williams J., Warui G. Trypanosoma congolense. I. Clinical observations of experimentally infected cattle. Exp Parasitol. 1974 Aug;36(1):6–19. doi: 10.1016/0014-4894(74)90107-6. [DOI] [PubMed] [Google Scholar]

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