Expression of VEGF-A and PlGF in human normal bone marrow.

(A) Expression of VEGF-A in the cytoplasm of erythroblastic island cells (APAAP technique, naphtol fast red) (black arrows). (B,C) Expression of VEGF-A (green, panel B) and glycophorin-A (red, panel C) examined by immunofluorescence. (D) Coexpression in erythroblasts is demonstrated by double immunofluorescence (yellow). (E) Expression of PlGF in the cytoplasm of erythoblastic island cells (APAAP technique, naphtol fast red) (black arrow). (F,G) Expression of PlGF (green, panel F) and glycophorin-A (red, panel G) analyzed by immunofluorescence. (H) Coexpression in erythroblastic cells is demonstrated by double immunofluorescence (yellow). (I) Double-immunoenzymatic staining: few macrophages stained in red with CD68 (PG-M1) (APAAP method, naphtol fast red) (black arrow). Macrophages are surrounded by VEGF-A–positive erythroblasts (APAAP method, NBT/BCIP revelation) (white arrow). (J) Erythroblasts showing cytoplasmic staining for VEGF-A (APAAP technique, naphtol fast red) are located in the vicinity of a sinusoid.