title: Bursa-independent origin of Fc IgG receptor-bearing lymphocytes in chickens.
abstract: On the basis of performed studies the following observations indicate that there is a bursa-independent origin of lymphocytes with Fc IgG receptors: (a) the first appearance of Fc positive cells is in fetal liver and bone marrow, (b) a relative low percentage of Fc receptor cells, as compared to B cells, occurs in the bursa during the embryonic and post-hatching period, (c) a far lower percentage of Fc positive cells than B cells is found in the spleen, (d) a normal level of Fc positive cells occurs in bursectomized birds, (e) a majority of these cells do not possess thymic or bursa antigen or surface immunoglobulin.
mesh_terms: D000818:Animals; D001665:Binding Sites; D002060:Bursa of Fabricius / Q000276:immunology*; D002454:Cell Differentiation; D002645:Chickens; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D008214:Lymphocytes / Q000166:cytology / Q000276:immunology*; D011947:Receptors, Antigen, B-Cell / Q000032:analysis; D012397:Rosette Formation; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D011947:Receptors, Antigen, B-Cell