HLA and malignancy : proceedings of a symposium presented by Roswell Park Memorial Institute, Buffalo, New York, August 19-20, 1976 / editor in chief: Gerald P. Murphy; associate editors: Elias Cohen, John E. Fitzpatrick, David Pressman.

Date:
1977
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Licence: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

Credit: HLA and malignancy : proceedings of a symposium presented by Roswell Park Memorial Institute, Buffalo, New York, August 19-20, 1976 / editor in chief: Gerald P. Murphy; associate editors: Elias Cohen, John E. Fitzpatrick, David Pressman. Source: Wellcome Collection.

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    Genetic and Immunologic Considerations of the HLA System of Human Lymphocytes and Tissues D. Bernard Amos and Armead H. Johnson The internationally recognized components of the HLA region are genetic loci designated HLA-A, B, C, and D. Of these, HLA-A and В code for glycopro¬ teins of MW approximately 45,000 daltons to which are bound, noncovalently, /32-microglobulin molecules of MW 11,ООО daltons. The HLA-C locus product is also a glycoprotein associated with a ]32-microglobulin molecule. However, the HLA-C glycoprotein is less well-characterized than the A or В locus products which have been analysed for amino acid composition and partially sequenced. The nature of the HLA-D gene product is unknown. Alleles of the A, B, and С loci are distinguished through the reactions of carefully selected alloantisera, usually obtained from parous women. From studies within families the codominant inheritance of alleles of the A, B, C, and D loci as a unit, called a haplotype, has been established; and from studies in families which include a recombinant, the map order of the loci of the HLA sys¬ tem has been established. It has been shown that the assortment of alleles on the haplotype is nonrandom. From population studies, gene frequencies have been determined. From a knowledge of the frequency of alleles of the A and В loci the frequency wdth which a given A allele should pair with a given В allele can be calculated. Most combinations of alleles fit the expectation, but a few occur together more frequently than would be expected by chance. This phenomenon is called linkage-disequilibrium (delta). High delta (Л) values have been reported between some A and В alleles; high Д are common between В and D; and very high Л are found between В and C. Alleles of HLA-D can at present be identified with certainty only through a special form of mixed lymphocyte culture (MLC) reaction called a typing cell response. This procedure uses lymphocytes from individuals who are homozy- 1 HLA and Malignancy, pages 1—7 © 1977 Alan R. Liss, Inc., New York, N.Y.