Immunophenotypic profile of nucleated erythroid progenitors during maturation in regenerating bone marrow.

This study introduces an in-depth flow cytometric method for the analysis of nucleated erythroid progenitors during bone marrow regeneration. Initial immunophenotypic analysis with the conventional erythroid-associated markers CD36, CD71 and CD235a was supplemented with the analysis of additional markers, including CD105, CD117, CD45, CD38 and cell-scattered light characteristics. Our data show that the expression of CD105 and CD117 is critical for the distinction between four phenotypically different developmental stages of nucleated erythroid progenitors: pro-erythroblasts, basophilic erythroblasts, polychromatophilic erythroblasts and orthochromatophilic erythroblasts. CD105 antigen expression was specifically associated with pro-erythroblasts and basophilic erythroblasts, whereas CD117 was expressed at the earliest pro-erythroblast stage. Both antigens were progressively lost throughout the course of differentiation. These data allow for the identification of aberrant erythroid development in acute erythroid leukemia or myelodysplastic syndrome.