Generation of HLA Class I Transfected Target Cell Lines

Normal human lymphoblastoid cell lines (LCLs) express six classical class I HLA genes from three gene loci, HLA-A, HLA-B, and HLA-C, which are located within the major histocompatibility complex (MHC). Because of the extensive allelic polymorphism of HLA class I genes, cell lines from heterozygous individuals can express up to six different class I alleles (1 ). Class I phenotypes, as well as other properties of different lymphoblastoid target cells, can therefore be very heterogeneous. Hence, in investigating the effects on and specificity of class I recognition by natural killer (NK) cells, it has proved useful to use transfected target cells that express only one class I allele, so that the effects of individual class I allotypes can be compared directly using the same target cell background.