Immunobiology of malignant B cells and immunoregulatory cells in B-chronic lymphocyte leukemia

The clonal excess of B cells in B-chronic lymphocytic leukemia (B-CLL) plays an important part in the basic disease process, secondary lymphomas, and autoimmune phenomema. Detailed investigations to characterize the dysfunction of the B-CLL B cell have been limited by misplaced beliefs that the clonal B-CLL B cell is 'well differentiated' and 'inert immunologically'. Many investigations have demonstrated that B-CLL B cells are not inert, but may be induced to further differentiate in the presence of the appropriate immunoregulatory signal(s). Recent studies have identified that normal B-cell function involved a complicated and multiphasic process consisting of an activation process, a proliferative response, and a final differentiation stage. It is not clear how the malignant B-cell dysfunction in B-CLL relates to these defined processes of normal B-cell function. The ability to precisely define the nature of the defects in the clonal B cells of B-CLL might provide a more complete understanding of the relationship of these cells to normal B-cell development and differentiation and, thus, alter our current perspectives on the pathophysiology and therapy of B-CLL.