Abnormalities in T-cell associated rearrangement of T-cell receptor gamma chain genes in B-cell chronic lymphocytic leukemia.

Non-random rearrangement of genes encoding the gamma chain of the T-cell antigen receptor is known to occur in a developmentally regulated fashion during thymocyte differentiation. We show here that peripheral blood T lymphocytes from patients with B-cell chronic lymphocytic leukemia display marked abnormalities in the spectrum of gamma variable region gene rearrangements compared with normal peripheral blood. Of seven patients studied, all displayed a reduction of rearrangements into V9 (subgroup V II), while two cases had, in addition, over-representation of specific rearrangements involving subgroup V I; one V 2/4, the other V 5. These observations have a number of implications relevant to mechanisms of disease pathogenesis, and may provide new insight into the basis of T-cell dysfunction that is frequently associated with this condition.