Rearrangement and expression of beta-T-cell receptor and immunoglobulin genes in established Ph1 chronic myelogenous leukemia cell lines.

We have determined the arrangement and expression of immunoglobulin (Ig) and beta-T-cell receptor (TCR) genes in six established Philadelphia chromosome-positive (Ph1) chronic myelogenous leukemia (CML) cell lines, and correlated these results with their phenotypic characteristics. Three cell lines with nonlymphoid characteristics, EM2, EM3, and K562, did not demonstrate rearrangement or expression of Ig or beta-TCR genes. A new cell line, MB, with a mature B-cell phenotype recently established in our laboratory, contained light and heavy chain immunoglobulin gene rearrangements and expressed mature Ig RNA. In a cell line with an early lymphoid phenotype, BV173, this analysis showed rearrangement of Ig heavy chain and beta-TCR genes, unrearranged Ig light chain DNA, and expression of only an immature beta-TCR transcript. This line provides evidence for T-cell lineage involvement in Ph1 CML. One cell line without markers of any cell type, KCL-22, demonstrated rearranged, unexpressed Ig heavy chain genes, suggesting these cells are at the very earliest stages of lymphoid differentiation. These lines should provide valuable tools to dissect the molecular biology of differentiation in CML and in early lymphocytes.