ABNORMAL PLATELET VON-WILLEBRAND-FACTOR (VWF) AS A MARKER OF ABNORMALFUNCTION IN MEGAKARYOCYTIC DYSPLASIA

The myelodysplastic syndromes (MDS) are neoplastic disorders of the he mopoietic system; multilineage involvement is also evidenced by specif ic cellular dysfunctions. The von Willebrand factor (VWF), synthesized and processed in the megakaryocytes (MK), is stored in the alpha gran ules of the platelets., The platelet vWF multimeric pattern was studie d in 18 patients with MDS, and in 4 with pernicious anemia (PA), to in vestigate whether the processing of vWF is abnormal in the megakaryocy tic dysplasia. An abnormal multimeric pattern was observed in 10/18 MD S and 4/4 PA patients. The abnormality of this specific protein is the discrete expression of the basic disorder, and is reversible when hem opoiesis is normalized, Although the data do not allow any conclusion, abnormal synthesis is the likely explanation of the abnormality. (C) 1995 Wiley-Liss, Inc.