L-SELECTIN EXPRESSION IN CD34 POSITIVE CELLS IN CHRONIC MYELOID-LEUKEMIA

L-selectin is a cell adhesion molecule, expressed on leukocytes and in volved in the regulation of leukocyte traffic. This adhesion receptor is implicated in hematopoiesis by the interaction of hematopoietic ste m cells and progenitors to stroma in the bone marrow microenvironment. We found that L-selectin expression on CD34(++) cells from patients w ith chronic myelogenous leukemia (CML) is decreased or deficient, refl ecting one of the features of malignant CML progenitors. In this revie w, we briefly describe the structure and function of L-selectin, and i ts role in hematopoiesis and its expression in leukemia and lymphoma. Finally, we discuss the abnormal adhesiveness of CML, progenitor cells , and the role of L-selectin in this defect.