Human erythrocyte membrane enzymes: current status and clinical correlates.

By Stanley L. Schrier T HE PAST TWENTY YEARS have seen a remarkable growth in information concerning the metabolism of the human erythrocyte. It became apparent that, depending on the method of preparation, some of the enzymes of the human erythrocyte can be recovered partially or totally in an operationally defined membrane fraction. Therefore, there now exists a substantial body of information relating to the membrane-associated enzymes of the human erythrocyte. Attempts have been made to classify these enzymes, to indicate their orientation, and to propose specific physiologic functions for them. As a subject of interest for the hematologist, there is good evidence that acquired and genetically determined disorders of the human erythrocyte may involve disordered erythrocyte membrane function. In more general terms, the human erythrocyte membrane has been a favorite subject for students of plasma membrane biology because of its ready availability as a plasma membrane preparation free ofother intracellular membranes.