CD13 (Myeloid Cell Marker)

CD13 (aminopeptidase N) is a surface marker primarily of myeloid-lineage cells — neutrophils, monocytes, macrophages, certain dendritic cells and myeloid progenitors — and is commonly used in diagnosing and classifying acute myeloid leukemia. It’s also expressed on various non-hematopoietic cells (endothelium, epithelium, kidney, intestine) and some solid tumors, so context matters for interpretation.

Yes. CD33 (SIGLEC‑3) is a myeloid-lineage cell surface marker expressed on mature myeloid cells (monocytes, granulocytes) and myeloid progenitors, and is commonly present on acute myeloid leukemia blasts. It is largely absent on normal lymphoid cells. CD33 is used diagnostically and therapeutically (targeting AML), though expression can vary between individuals and disease states.

CD13 positive means cells express the CD13 protein (aminopeptidase N) on their surface. It’s a myeloid-lineage marker found on neutrophils, monocytes and some epithelial cells. Detection by flow cytometry helps classify leukemias and monitor disease; CD13 also participates in peptide cleavage, cell adhesion and can act as a viral receptor. Expression patterns aid diagnosis, prognosis and treatment decisions.

CD13 (aminopeptidase N) is expressed primarily on myeloid cells—monocytes, macrophages, neutrophils and dendritic cells—and on hematopoietic progenitors. It’s also present on many nonhematopoietic cells, including intestinal brush-border and renal proximal tubule epithelium, respiratory epithelium, vascular endothelium, fibroblasts and placenta, and is often upregulated in various tumors. It functions in peptide trimming, angiogenesis and cell migration.

The hallmark genetic marker of chronic myeloid leukemia is the BCR‑ABL1 fusion (Philadelphia chromosome). Myeloid lineage is shown by myeloperoxidase (MPO) positivity and surface antigens CD13, CD33 and CD117; blasts often express CD34 and CD45. Diagnosis combines morphology, immunophenotyping, cytogenetics and molecular testing to confirm and guide treatment.

Yes. Neutrophils express CD13 (aminopeptidase N), a myeloid cell surface enzyme found on granulocytes including neutrophils. CD13 contributes to peptide cleavage and can influence migration and activation; its surface levels may change with cell state and activation. It is routinely detectable on circulating neutrophils by flow cytometry and used as a myeloid marker.