Early separation of B and T lymphocyte precursors in chick embryo - PubMed (original) (raw)
Early separation of B and T lymphocyte precursors in chick embryo
E Houssaint et al. J Exp Med. 1991.
Abstract
Embryonic chimeras were used to demonstrate an early separation of chicken T and B cell precursors. Genetically polymorphic cell surface antigens, Bu-1 and Ov, which are expressed on cells of the B and T lineage, respectively, are useful markers in adoptive cell transfer studies. Allelic products Bu-1a and Bu-1b can be detected with monoclonal antibodies (mAbs) L22 and 11G2, respectively, and the Ov antigen with mAb 11A9. Chimeric chickens were constructed by reconstituting irradiated 14-d Ov- H.B19 embryos with the sorted Bu-1+ or Bu-1- fractions of spleen cells from age-matched H.B19 Ov+ embryos. Chimeras were analyzed, 3-4 wk after hatching, for the presence of Ov+ cells in the bursa, thymus, spleen, and peripheral blood lymphocytes. T cell precursors giving rise to thymocytes and peripheral T cells were present only in the Bu-1-, but not in the Bu-1+, fraction. We previously demonstrated that, in contrast, all B cell precursors in spleen from 14-d embryos are exclusively present in the Bu-1+ fraction. We also analyzed the immunoglobulin light chain gene rearrangement in these populations by polymerase chain reaction. We show here that VJ recombination occurs in the Bu-1+, but not in the Bu-1-, fraction of spleen. These data demonstrate an early commitment to the B cell lineage, which occurs before the colonization of the bursa of Fabricius. Segregation of B cell precursors from the other hemopoietic precursors, and consequently separation of T and B cell precursors, occurs before the colonization of the primary lymphoid organs.
References
- Aust J Exp Biol Med Sci. 1962 Oct;40:373-87 - PubMed
- Dev Biol. 1966 Aug;14(1):40-51 - PubMed
- Proc Natl Acad Sci U S A. 1990 Dec;87(23):9416-20 - PubMed
- J Immunol. 1990 Dec 1;145(11):3601-9 - PubMed
- Science. 1988 Jan 29;239(4839):487-91 - PubMed