title: B cell precursors in chick embryos surgically bursectomized at 72 h of incubation.
abstract: To determine the presence of precursor B cells in chick embryos surgically bursectomized at 72 h of incubation (E-Bx) we studied chick chimeras that were produced by establishing parabiotic connections between blood vessels of chorioallantoic membranes of normal and surgically bursectomized chick embryos. Using sex chromosomes and a B cell alloantigen (Bu-1a) as markers we showed that chick embryos bursectomized at 72 h of incubation contain B cell precursors capable of colonizing the bursa of Fabricius and developing into B lymphocytes. The repopulation capacity of 14-day-old embryonic spleen cells from E-Bx recipients was tested by transferring them into age-matched X-irradiated Bu-1-disparate embryos. The results show that B cell precursors are present in 14-day spleen of chick embryos bursectomized at 72 h of incubation. These precursors carry the Bu-1 B cell alloantigen, suggesting that commitment to the B cell lineage can take place in the absence of bursa.
authors.affiliation: Basel Institute for Immunology, Switzerland.
authors.forename: O
authors.initials: O
authors.lastname: Lassila
authors.forename: A
authors.initials: A
authors.lastname: Alanen
authors.forename: O
authors.initials: O
authors.lastname: Vainio
authors.forename: E
authors.initials: E
authors.lastname: Houssaint
authors.forename: J R
authors.initials: JR
authors.lastname: Pink
authors.forename: W T
authors.initials: WT
authors.lastname: Weber
mesh_terms: D000367:Age Factors; D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis; D001402:B-Lymphocytes / Q000166:cytology*; D002060:Bursa of Fabricius / Q000196:embryology*; D002454:Cell Differentiation; D002642:Chick Embryo; D002678:Chimera; D010227:Parabiosis; D013154:Spleen / Q000196:embryology* / Q000276:immunology
chemical_list: D000944:Antigens, Differentiation, B-Lymphocyte