Use of monoclonal anti-actin as a megakaryocyte marker in paraffin wax embedded bone marrow biopsy specimens.

Monoclonal anti-actin was used as a marker of megakaryocytes in Zenker's fixed, paraffin wax embedded bone marrow tissue, using an immunoperoxidase staining method. Twenty bone marrow samples were studied, including controls, and different myeloproliferative and myelodysplastic syndromes. The results were compared with those obtained using factor VIII related antigen (F VIII RAg) immunolabelling. Anti-actin is as good a marker for megakaryocytes as anti-FVIIIRAg and is potentially clinically useful when morphological identification is difficult, when bone marrow aspiration is unsuccessful, or when quantitative evaluation of tissue sections is required.