The adhesion molecule E-cadherin and a surface antigen recognized by the antibody 9C4 are selectively expressed on erythroid cells of defined maturational stages.

摘要: The antigen expression of immature erythroid bone marrow cells was studied using two recently generated monoclonal antibodies (mAb), mAb 67A4 and 9C4, with specificities for the epithelial cell adhesion molecule E-cadherin (E-cad; 67A4), a novel 110 kDa differentiation (mAb 9C4) unknown molecular structure. Pappenheim staining FACS-purified labeled 9C4 anti-glycophorin A (GA) revealed that majority 9C4+GA- 9C4+GA+ consisted erythroblasts. In contrast, E-cad-positive population comprised normoblasts While E-cad+GA- fraction contained mainly erythroblasts basophilic normoblasts, E-Cad+GA+ enriched in orthochromatic polychromatophilic normoblasts. By colony assays affinity column-purified it could be shown forming units (CFU-E) were burst (BFU-E) depleted 9C4- fractions. Flow cytometric analysis double-labeled anti-CD71, anti-CD117, anti-CD34, or anti-GA about 90% coexpressed CD71, 70% positive CD117, 50% GA, only 5% CD34. pattern similar to E-Cad exception minority 9C4-positive GA. Lymphoid myeloid markers negative on both E-Cad- populations. these studies we describe identification new mAb-defined which is specifically expressed CFU-E(9C4) demonstrate not but also erythropoietic defined maturational stages.