{"type":"root","children":[{"type":"paragraph","children":[{"type":"text","value":"CD13 (also known as aminopeptidase-N) is expressed on the majority of peripheral blood monocytes and granulocytes. It is also expressed by the majority of acute myeloid leukemias, chronic myeloid leukemias in myeloid blast crisis, a smaller percentage of lymphoid leukemias and myeloid cell lines according to literature. CD13 is absent in normal lymphocytes, platelets and erythrocytes. CD13 is also present on fibroblasts, endothelial cells, epithelial cells from renal proximal tubules and intestinal brush border, bone marrow stromal cells, osteoclasts, and cells forming bile canaliculi."}]}]}