title: Comparison of IgD+ and IgD- thoracic duct B lymphocytes as germinal center precursor cells in the rat.
abstract: Genetically marked thoracic duct B cell subpopulations rich in either IgD+ or IgD- B cells were transferred to non-irradiated, congenic rats in order to compare the capacities of IgD+ versus IgD- B cells to form germinal centers (GCs). This comparison was made quantitatively based on flow cytometric analyses of lymph node cells prepared from chimeric rats 7 days after s.c. immunization. Donor-origin and host-origin B cells were distinguished using anti-Igk antibodies, and GC B cells were distinguished from other B cells in suspension by their lack of labeling with the mAb HIS22. IgK+ HIS22- lymph node cells corresponded well to GC B cells: they contained many large cells, were IgM+ but mostly IgD-, expressed relatively lower levels of IgM than HIS22+ B cells, and increased in number and frequency in response to antigen. Results from flow cytometric analyses, corroborated by immunofluorescence histochemical studies, showed that cell-for-cell, IgD- B cells from GCs much more efficiently than IgD+ cells. B cell populations enriched for IgD- cells became relatively more distributed to GCs than to other lymph node B cell areas and gave rise to many more GC B cells of donor origin per transferred B cell than whole, unseparated thoracic duct B cells (for which greater than 97% were IgD+). IgD- B cells from rats primed deliberately with antigen also became relatively more distributed to GCs and gave rise to more GC B cells of donor origin than either IgD+ B cells from primed donors or IgD- B cells from unprimed donors.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Sir William Dunn School of Pathology Oxford University, UK.
authors.forename: R H
authors.initials: RH
authors.lastname: Vonderheide
authors.forename: S V
authors.initials: SV
authors.lastname: Hunt
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002678:Chimera; D007126:Immunoglobulin Allotypes / Q000276:immunology; D007072:Immunoglobulin D / Q000378:metabolism*; D007156:Immunologic Memory; D008198:Lymph Nodes / Q000166:cytology; D008213:Lymphocyte Activation; D051381:Rats; D013897:Thoracic Duct / Q000166:cytology
chemical_list: D007126:Immunoglobulin Allotypes; D007072:Immunoglobulin D