Symposium: Cellular Immunity and the Immunotherapy of Cancer: Major Histocompatibility Complex/Human Leukocyte Antigen and Tumors: PDF OnlyBrowning M J; Krausa, P; Rowan, A; Hill, A B; Bicknell, D C; Bodmer, J G; Bodmer, W FJournal of Immunotherapy with Emphasis on Tumor Immunology: October 1993 - p 163-168 Buy Abstract Summary A system devised for tissue typing the human leukocyte antigen-A (HLA-A) locus from genomic DNA by the polymerase chain reaction (PCR) has been used to investigate abnormalities of HLA expression in a panel of 30 cell lines derived from colorectal adenocarcinomas, by comparison of the HLA-A locus genotype with surface expression of HLA. Eleven cell lines gave single HLA-A locus specificity on PCR typing, suggesting that loss of HLA alleles is a common abnormality. In one of these cell lines the loss of an HLA-A locus allele was confirmed by comparison with DNA from a lymphoblastoid B cell line derived from the same patient. In three cell lines, loss of expression of an HLA-A locus determinant was observed in spite of the presence of the relevant allele in genomic DNA. Three cell lines showed absent HLA expression associated with failure to express (32-microglobulin. These data indicate that at least three independent mechanisms were involved in the loss of HLA expression on the colorectal tumor cell lines. © Lippincott-Raven Publishers.