title: Hematopoietic differentiation cell surface antigen switching in the bone marrow of different aged chickens.
abstract: Immune cytolysis and immunofluorescence were used to examine chicken fetal antigen CFA) and chicken adult antigen (CAA) expression on the differentiation/maturation series of definitive erythroid cells obtained from the bone marrow of different aged chickens. We found that erythroid cells undergo changes in CFA/CAA antigenic expression dependent on their differentiation/maturation stages as well as the developmental age of the chicken. All differentiation/maturation stages of erythroid cells in the bone marrow of 12 and 18-day-old embryos express CFA only. Erythroblasts obtained from 7-day post-hatched chickens express either CFA or CAA. All three CFA/CAA phenotypes (i.e., CFA, CAA, and CFA + CAA) are observed in subsequent maturation stages, but only the CFA + CAA phenotype is observed in mature erythroid cells in the bone marrow of 7-day post-hatched chickens. Erythroblasts from 62 day post-hatched chickens exhibit all three CFA/CAA phenotypes. Cells in the subsequent maturation stages express various CFA, CAA, or CFA + CAA phenotypes resulting in a majority of the mature erythrocytes expressing both CFA and CAA, and a small population of mature erythrocytes expressing CAA only. Erythroblasts from adult chickens express both CFA and CAA; however, CFA is lost during erythroid maturation resulting in mature erythrocytes which express CAA only. These studies indicate that both the erythroid differentiation/ maturation stage and the developmental age of the chicken influence CFA and CAA antigenic expression on erythroid cells undergoing cellular differentiation/maturation in the bone marrow.
mesh_terms: D000375:Aging; D000818:Animals; D000941:Antigens / Q000032:analysis*; D000954:Antigens, Surface / Q000032:analysis*; D001853:Bone Marrow / Q000196:embryology / Q000254:growth & development* / Q000276:immunology; D002454:Cell Differentiation; D002642:Chick Embryo; D002645:Chickens; D003602:Cytotoxicity, Immunologic; D005455:Fluorescent Antibody Technique; D006412:Hematopoietic Stem Cells / Q000276:immunology / Q000502:physiology*; D000949:Histocompatibility Antigens Class II / Q000032:analysis*
chemical_list: D000941:Antigens; D000954:Antigens, Surface; D000949:Histocompatibility Antigens Class II; C041136:Ia-like antigens, avian