Article

An acquired form of Bernard Soulier syndrome associated with acute myeloid leukemia.

Regional Department of Immunology, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, United Kingdom.
Saudi medical journal (Impact Factor: 0.55). 08/2005; 26(7):1095-8.
Source: PubMed

ABSTRACT To investigate glycoprotein-1b (GP-1b) expression on platelets from patients with acute myeloid leukemia (AML).
Purified platelets, obtained from AML-patients and normal control subjects, were examined for surface membrane GP1b-expression by flow cytometry and GP1b-mediated aggregation responses by aggregometry. The level of elastase in plasma from patients and controls was measured by enzymed-linked immunosorbent assay. The whole of this work was carried out at the University of Liverpool, Liverpool, United Kingdom during the period of 1994-2001.
Platelets from the majority of AML-patients showed reduced GP1b-expression and reduced GP1b-mediated aggregation responses. Reduction in platelet GP1b-expression was associated with increased plasma elastase levels.
The present study suggests that elastase, released from leukemic blasts, degrades platelet GP1b, resulting in dysfunctional circulating platelets in AML-patients. These results could explain the bleeding disorders observed in these patients.

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