Adenosine 3′,5′-monophosphate protein kinase isoenzyme distribution in lymphocytes from normal individuals and patients with chronic lymphocytic leukaemia

Two major isoenzymic forms of adenosine 3′,5′-monophosphate (cyclic AMP)-dependent protein kinase were resolved by DEAE cellulose chromatography of cytosols of normal human lymphocytes and of abnormal (colchicine ultrasensitive) lymphocytes from patients with chronic lymphocytic leukaemia (CLL). With only one exception the activity of type I protein kinase exceeded that of type II in normal lymphocytes, whilst in CLL the activity of the type II isoenzyme exceeded that of the type I. The total activity of protein kinase was approximately the same in normal and CLL lymphocytes. This difference in isoenzyme distribution may reflect the immaturity of CLL lymphocytes.