Chicken fetal antigen expression on the definitive erythroid maturation series in the bone marrow of the adult chicken.

Chicken fetal antigen (CFA) describes a membrane developmental antigen system present on embryonic and fetal erythroid cells that is present during development, but is absent on erythrocytes of mature chickens. In this study, CFA was detected by indirect immunofluorescence and correlated with six stages of morphological maturation of erythroid cells. All cells in the erythroid series through the late polychromatic erythrocyte (reticulocyte) stage were found to possess CFA. Fluorescent intensity and staining patterns of the definitive erythroid series demonstrated CFA concentration increase and distribution pattern change throughout erythroid maturation.