HLA-DR antigen and gene frequencies were studied in 150 unrelated Koreans in Seoul. HLA-DR4 was the most common DR specificity encountered and HLA-DR1 and -DR3 occurred with the lowest frequencies. The frequency of HLA-DR blank allele was 27.1%. HLA-B:DR haplotypes involving positive delta values differing significantly from zero were DR1:B7, DR2:Bw22, DR3:B17, DR5:Bw35, DRw6:B17, DR7:B12, DR7:B13, and DRw8:Bw16. The supertypic groups (MT1, MT2 and MT3) differ somewhat in frequencies from Other populations. These findings suggested that the Korean population, while having many similarities in HLA-DR antigen frequencies with those of neighboring Orientals, has not only different features in the distribution of HLA-DR antigens but also has unique HLA-B:DR haplotypes.
Gene Frequency ; HLA Antigens/analysis* ; HLA-B Antigens ; HLA-DR Antigens ; Haploidy ; Histocompatibility Antigens Class II/analysis* ; Human ; Korea ; Mongoloid Race*

In a previous report, it was felt that the rat tumor cell line, T-333, was a mixture of heterogeneous cells with different characteristics with respect to karyotype, tumorigenicity, and response to Rolls Sarcoma virus (RSV) infection. These characteristics of hetero-geneous cell subpopulations could be selected by use of different culture substrates. In this experiment, diversity of the cells in response to complement mediated cytolysis employing syngeneic rat anti-sera was studied. More than 50% of the glass grown cells were lysed while only 19% of the plastic grown cells were lysed by the specific immune sera of syngeneic rats. This finding suggests that growth in plastic culture wares selects cells with resistance to complement mediated cytolysis. It seems likely that the previously reported enhanced tumorigenicity of plastic grown T-333 cells is due to clonal selection of cell subpopulations which can better tolerate at least one arm of the in vivo immune surveillance system.
Animal ; Cells, Cultured ; Cytotoxicity, Immunologic ; Neoplasms, Experimental/immunology* ; Plastics ; Rats ; Rats, Inbred Strains