Name:CD34 Antibody clone QBEnd/10
Description and aplications: The QBEnd10 antibody is a class II monoclonal antibody that recognizes an epitope of CD34 that is resistant to neuraminidase and sensitive to glycoprotease and chymopapain. CD34, a single chain transmembrane glycoprotein, is detected in bone marrow precursors, including normal lymphoid precursors or hematogonias where it may act as lectins ligand of these cells with the bone marrow stroma. CD34 expression disappears from the surface of all haematological series during maturation. Megakaryocytes may show varying positivity for CD34. This antibody shows reactivity with most endothelial
cells, expressed on the luminal surface and interdigitating membrane processes between endothelial cells, but is absent in large venous and arterial vessels. CD34 is also absent in sinusoids of the spleen, liver and placenta. The lymphatic vessels are generally weakly stained. CD34 is also expressed in fibroblast-like dendritic cells localized in liver portal tracts and in Peyer’s patches in wound repair phase. In tumors, CD34 is detected in myeloid blasts of myelodysplastic syndromes and in most cases of acute myeloid leukemias and lymphoblast of the acute lymphoblastic leukemias. Mature B cell lymphomas, B and T cell leukemias are all negative for CD34.
Most vascular tumors and sarcomas including Kaposi hemangiosarcomas are positive for CD34. CD34 is expressed in most cases of dermatofibrosarcoma protuberans (while fibrous histiocytoma is negative), solitary fibrous tumor, lipomas (particularly the spindle cell) and liposarcomas, gastrointestinal stromal (GIST) (strongly positive in 80% of cases coinciding with the expression of CD117) and meningiomas in a variable proportion of cases. Moderate expression was detected in cutaneous leiomyomas and weak staining may be observed in tumors of smooth muscle of the uterus or soft tissue.
Composition: anti-human CD34 mouse monoclonal antibody purified from ascites fluid by Protein A chromatography. Prepared in 10mM PBS, pH 7.4, with
0.2% BSA and 0.09% sodium azide
Immunogen: Detergent solubilized vesicular suspension prepared from a perfusate of human term placenta.