Hypoxanthine-guanine phosphoribosyltransferase activity in normal and leukaemic lymphocytes.

The levels of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) were determined in lymphocytes from normal people and patients with chronic lymphocytic leukaemia (CLL). The HGPRT level in the total lymphocyte population from patients with CLL was lower than that from normal subjects. The HGPRT activity was higher in normal non-T cells than normal T cells. The enzyme activity in CLL B cells was lower than in CLL T cells. The HGPRT level was higher in CLL T cells than in normal T cells; these data suggest CLL T cells differ biochemically from their normal counterparts.