The distribution of lysozyme, alpha-1-antitrypsin, and alpha-1-antichymotrypsin in normal hematopoietic cells and in myeloid leukemias: an immunoperoxidase study on cytocentrifuge preparations, smears, and paraffin sections.

Blood and bone marrow samples from 20 individuals with reactive conditions and 26 cases of acute and chronic myeloid leukemias were tested for the presence of lysozyme, alpha-1-antitrypsin (alpha-1-AT), and alpha-1-antichymotrypsin (alpha-1-ACT). We compared the reactivity of samples in smears, cytocentrifuge preparations, and paraffin sections. Lysozyme, alpha-1-antitrypsin, and alpha-1-antichymotrypsin were found only in polymorphonuclear leukocytes and monocytes and their precursors. Lymphocytes, E-rosetting cells, Con A-activated lymphocytes, natural killer (NK) cells, red blood cells, erythroblasts, and megakaryocytes were consistently negative. Leukemic myeloblasts showed definite reactivity for both alpha-1-antitrypsin and alpha-1-ACT, but not for lysozyme. By contrast, lysozyme was present in poorly differentiated leukemic monoblasts, while alpha-1-antitrypsin and alpha-1-antichymotrypsin showed only weak reactivity. More mature myeloid and moncytic cells showed positive staining for all three antigens tested with differences in staining distribution and intensity. In four cases of chronic myeloid leukemia (CML), circulating mature polymorphonuclear leukocytes were deficient in both lysozymne and alpha-1-antitrypsin. The use of lysozyme, alpha-1-antitrypsin, and alpha-1-antichymotrypsin identifies normal and leukemic cells of the myeloid-monocytic series at all stages of maturation and is applicable to a variety of sample preparations.