背景介绍 CD34 (Cluster of Differentiation-34) is a single-pass transmembrane phosphoglycoprotein and a stem cell antigen.  It is a receptor for L-Selectin (CD62L) and CrkL ligands, as well as E- and P-Selectin in the bone marrow extracellular matrix.  It can act both as a cell adhesion molecule and as an adhesion blocking molecule against mast cells, dendritic precursors and eosinophils.  CD34 is most commonly characterized by its expression on the surface of hematopoietic stem cells (HSC), and is therefore utilized for positive selection and counting of CD34⁺ cells in clinical bone marrow transplants.  CD34^(-) HSCs have also been identified, which exhibit a distinct progenitor profile.   CD34 bears a controversial identity as a mesenchymal stromal cell (MSC) marker, the evidence for which is highly context-dependent.  In addition, CD34 is expressed by other progenitor cell types such as quiescent keratocytes, stem cells within the hair follicle that replace epithelial layers of the skin, and within sub-populations of interstitial cells of Cajal (ICC).  More recently CD34 has been identified as a potential predictor of neoadjuvant chemotherapy efficacy in cervical cancer patients, and when found in tumor stroma, is associated with better colorectal cancer survival. 产品介绍 Recombinant clonal CHO stable cell line constitutively expressing full length human CD34 protein. The surface expression of CD34 in this cell line was validated by flow cytometry.