Background
Hematopoiesis occurs in the bone marrow, producing whole spectrum of blood cells to maintain homeostasis. In addition to light microscopy, chromosome analysis, and polymerase chain reaction, flow cytometry is a feasible, fast, and quantitative analysis method to examine hematological diseases. However, because the lack of sufficient specific cell markers, dyserythropoiesis diseases are not easy to be identified by flow cytometry.
Methods: Bone marrow samples from C57BL/B6 mice and one healthy donor were analyzed using traditional 2-marker (CD71 and glycophorin A) flow cytometry analysis. After cell sorting, gene expression of membrane proteins in early and late erythropoiesis precursors and in non-erythroid cells were characterized using microarray analysis.
Results
Among characterized gene candidates, aquaporin 0 (AQP0) expresses as a surface protein in early and late stage erythropoiesis precursors and is not expressed on non-erythroid cells. In this present study, with assistant of AQP0 staining, we can define up to 5 stages of erythropoiesis in both mice and human bone marrow using flow cytometry. In addition, because patients with dyserythropoiesis generally displayed a reduced population of APQ0 high cells as compared to the normal subjects, analyses results also suggested that the levels of APQ0 high cells in the early erythropoiesis may serve as novel biomarker to distinguish normal versus dysregulated erythropoiesis.
Conclusions
AQP0 was successfully demonstrated as an erythroid differentiation marker. The expression levels of AQP0 are down-regulated in patients with dyserythropoiesis, implicating a critical and functional role of AQP0 in erythropoiesis. Accordingly, the levels of AQP0 high population in early erythroid precursor cells may serve as a reference parameter for diagnosing diseases associating with dyserythropoiesis.