Immunoglobulin V(H) gene expression in human B cell lines and tumors: biased V(H) gene expression in chronic lymphocytic leukemia
Leukemia, Lymphocytic, Chronic, B-Cell
We have studied frequencies of VH gene utilization in a panel of monoclonal Epstein-Barr virus (EBV)-transformed B cell lines derived from human adult and fetal tissues as well as in monoclonal B cells obtained from fresh chronic lymphocytic leukemia (CLL) samples. The results show that IgM-secreting EBV cell lines from both fetal and adult tissues utilize VH genes from particular families roughly in proportion to estimated family size, suggesting that the repertoire of sigM-positive B cells in both fetal and adult organs is 'normalized' with respect to the V(H) gene family. In contrast, we find a highly biased pattern of VH gene expression in CLLs. The significance of these findings is discussed in the context of mechanisms that could be involved in normal B cell repertoire development and in the process of malignant transformation of precursors of CLL.