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Immunochemical analysis of surface membrane antigens on erythrocytes infected with non-cloned SICA[ + ] or cloned SICA[ − ] Plasmodium knowlesi

Published online by Cambridge University Press:  06 April 2009

R. J. Howard  and
J. W. Barnwell
R. J. Howard
Affiliation:
The Laboratory of Parasitic Diseases, Malaria Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20205
J. W. Barnwell
Affiliation:
The Laboratory of Parasitic Diseases, Malaria Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20205
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The SICA[ − ] or non-agglutinable phenotype of Plasmodium knowlesi schizont-infected erythrocytes has been defined serologically but not biochemically. Similarly, non-cloned SICA[ + ] or agglutinable parasites have been shown serologically to express SICA or variant antigen(s) but the number and nature of such antigens have not been defined. Here we describe the immunochemical analysis of surface antigen expression on [125I]lactoperoxidase-labelled erythrocytes infected either with a SICA[ − ] elone or with non-cloned SICA[ + ] parasites using the methods developed for identification of variant antigens with cloned SICA[ + ] parasites. No 125I-labelled antigens in the size range Mr 190000–225000 were specifically immunoprecipitated from erythrocytes infected with the SICA[ − ] elone, even using homologous antisera produced by multiple infections or immunizations. Further, no125I-labelled proteins of this size were seen in detergent extracts of the SICA[ −] parasites that were not also seen with uninfected cells. We conclude that the SICA[ − ] phenotype reflects the absence of a variant antigen at the erythrocyte surface, as predicted by the serological assays. In contrast, with the non-cloned SICA[ + ] parasites, a complex group of proteins, Mr 195000–225000, was identified by [125I]lactoperoxidase labelling of intact infected erythrocytes. These proteins are SICA antigens since they not only share the characteristic detergent solubility properties and size range of SICA antigens identified previously with SICA[ + ] clones, but they were only immunoprecipitated by antisera which reacted specifically with the surface of infected erythrocytes. Agglutinating sera immunoprecipitated several of these 125I-labelled antigens. Sera specific for clones derived from this non-cloned SICA[ + ] population failed to agglutinate, but did react by indirect immunofluorescence with 10–16% of infected cells. These sera specifically immunoprecipitated single, quantitatively minor 125I-labelled antigens in this size range. The results suggest that a population of non-cloned SICA[+] parasites contains at least 10 different variant-antigen phenotypes. Indirect immunofluorescence was also performed against a non-cloned SICA[ + ] population derived by antigenic variation of a SICA[ + ] clone in vivo. The variant population contained at least 3 antigenically distinct SICA phenotypes, indicating that antigenic variation of clones may produce populations as antigenically heterogenous as antigenic variation of uncloned lines. It is therefore likely that natural malaria isolates contain a large number of different variant antigens.

Type
Research Article
Information
Parasitology , Volume 91 , Issue 2 , October 1985 , pp. 245 - 261
Copyright
Copyright © Cambridge University Press 1985

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References

REFERENCES

Aley, S. B., Babnwell, J. W., Daniel, W. & Howard, R. J. (1984). Identification of parasite Proteins in a membrane preparation enriched for the surface membrane of erythrocytes infected with Plasmodium knowlesi. Molecular and Biochemical Parasitology 12, 69–84.CrossRefGoogle Scholar
Barnwell, J. W., Howard, R. J. & Miller, L. H. (1982 a). The influence of the spleen on the expression of surface antigens on parasitized erythrocytes. In Malaria and the Red Cell, Ciba Fdn Symp. 94, pp. 117–36. Amsterdam: Associated Scientific Publishers.Google Scholar
Barnwell, J. W., Howard, R. J. & Miller, L. H. (1982 b). Altered expression of Plasmodium Knowlesi variant antigen on the erythrocyte membrane in splenectomized rhesus monkeys. Journal Of Immunology 128, 224–6.CrossRefGoogle ScholarPubMed
Barnwell, J. W., Howard, R. J., Coon, H. G. & Miller, L. H. (1983). Splenic requirement for antigenic variation and expression of the variant antigen on the erythrocyte membrane in cloned Plasmodium knowlesi malaria. Infection and Immunity 40, 985–94.CrossRefGoogle ScholarPubMed
Brows, I. N., Brown, K. N. & Hills, L. (1968). Immunity to malaria: The antibody response to Antigenic variation by Plasmodium knowlesi. Immunology 14, 127–38.Google Scholar
Brown, K. N. (1973). Antibody induced variation in malaria parasites. Nature, London 242, 49–50.CrossRefGoogle ScholarPubMed
Brown, K. N. & Brown, I. N. (1965). Immunity to malaria: Antigenic variation in chronic infections of Plasmodium knowlesi. Nature, London 208, 1286–8.CrossRefGoogle ScholarPubMed
Brown, K. N., Brown, I. N., Trigg, P. I., Phillips, R. S. & Hills, L. A. (1970). Immunity to malaria. II. Serological response of monkeys sensitized by drug-suppressed infection or by dead parasitized cells in Freund's complete adjuvant. Experimental Parasitology 28, 318–38.CrossRefGoogle ScholarPubMed
Brown, K. N. & Hills, L. A. (1974). Antigenic variation and immunity to Plasmodium knowlesi: Antibodies which induce antigenic variation and antibodies which destroy parasites. Transactions of the Royal Society of Tropical Medicine and Hygiene 68, 139–42.CrossRefGoogle ScholarPubMed
Chin, W., Contacos, P. G., Coatney, A. R. & Kimball, H. R. (1965). A naturally acquired quotidian-type malaria in man transferable to monkey. Science 149, 865.CrossRefGoogle Scholar
Hommel, M. & David, P. H. (1982). Plasmodium knowlesi variant antigens are found on schizont-infected erythrocytes but not on merozoites. Infection and Immunity 33, 275–84.CrossRefGoogle Scholar
Howard, R. J. & Barnwell, J. W. (1984). The detergent solubility properties of a malarial (Plasmodium knowlesi) variant antigen expressed on the surface of infected erythrocytes. Journal Of Cellular Biochemistry 24, 297–306.CrossRefGoogle ScholarPubMed
Howard, R. J., Barnwell, J. W. & Kao, V. (1983). Antigenic variation in Plasmodium knowlesi malaria: Identification of the variant antigen on infected erythrocytes. Proceedings of the National Academy of Sciences, USA 80, 4129–33.CrossRefGoogle ScholarPubMed
Howard, R. J., Barnwell, J. W., kao, V., Daniel, W. A. & Aley, S. B. (1982). Radio-iodination of new protein antigens on the surface of Plasmodium knowlesi schizont-infected erythrocytes. Molecular and Biochemical Parasitology 6, 343–67.CrossRefGoogle Scholar
Howard, R. J., Kao, V. & Barnwell, J. W. (1984). Protein antigens of Plasmodium knowlesi clones Of different variant antigen phenotype. Parasitology 88, 221–37.CrossRefGoogle ScholarPubMed
Laemmli, U. K. (1970). Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature, London 227, 680–5.CrossRefGoogle ScholarPubMed
Phillips, D. R. & Morrison, M. (1971). Exposed proteins on the intact human erythrocyte. Biochemistry 10, 1766–71.Google ScholarPubMed
Sheetz, M. P. (1979). Integral membrane protein interaction with Triton cytoskeletons of erythrocytes. Biochimica et Biophysica Acta 557, 122–34.CrossRefGoogle ScholarPubMed
Swanstrom, R. & Shank, P. R. (1978). X-ray intensifying screens greatly enhance the detection by autoradiography of the radioactive isotopes 32P and 125I. Analytical Biochemistry 86, 184–;92.CrossRefGoogle ScholarPubMed