Figure 4
From: CD14+ monocytes repress gamma globin expression at early stages of erythropoiesis
Inhibition of HbF expression by CD14+ cells occurs early during hematopoiesis/erythropoiesis. (A) Erythroblasts (CD71+/CD235low) were cultured with and without PBMC-isolated CD14+ cells as indicated in material and methods. Bar graph shows the mean fluorescent intensity of gamma globin expression as measured by flow cytometry. (B) Hematopoietic progenitors were sorted based on their expression of CD34 and CD36 expression. In short, CD34+CD36− represent hematopoietic stem and progenitors cells, CD34+CD36+ cells are committed to a megakaryoid/erythroid fate but no myeloid fate and CD34−CD36+ cells are pro-erythroblasts15. Cells were cultured in presence (solid bars) or absence of PBMC-isolated CD14+ cells (striped bars). The percentage of HbA and HbA/HbF cells was measured by flow cytometry and indicated on the y-axis. Note that the reduction of HbF/HbA populations by CD14+ cells is proportional to the immaturity of the progenitors (N = 3).
