A comparison of fresh and cultured T lymphocytes from patients with ataxia telangiectasia using T-cell subset markers and chromosome translocations.

Ataxia telangiectasia (A-T) is an autosomal recessive disorder in which patients show an unusual predisposition to lymphoid malignancies including T-cell leukaemia. We compare here the surface phenotypes of fresh and cultured A-T T cells. A total of 17 T-cell cultures from 8 A-T patients are compared with each other and with 5 T-cell cultures from normal individuals. The large, cytogenetically abnormal t(14;14) and t(X;14) clones in 2 of the patients both occurred only in the CD8+ population of T lymphocytes. There was no difference in the rate of growth of A-T T cells in vitro compared with those from normal individuals, although many of the original characteristics of the T cells were lost, including the cytogenetically abnormal clones seen in fresh A-T lymphocytes.