title: Characteristic cellular composition of germinal centers.
abstract: We established the method of isolating individually encapsulated germinal centers (GCs) from immunized spleen and analyzed single cell suspension of GCs by flowcytometry. In GCs, the high frequency of sIgG+ cells (29%) and sIgA+ cells (5%) was detected. Two-color flowcytometry analysis showed that GCs contained 27% of sIgM-IgG+ cells, in which isotype switch from IgM to IgG had occurred, and 5% of Bu1-IgG+ cells, which were differentiating into plasma cells. On the other hand, sIgM-IgG+ and Bu1-IgG+ cells were not detected in the bursa, which contained 95% of B cells and only 1% of T cells. CD4+ but not CD8+ T cells were detected in the light zone of GCs and these CD4+ T cells are supposed to play a key role in isotype switching and differentiation into plasma cells in GCs. These results clearly demonstrate that GCs provide a site for isotype switching and differentiation into plasma cells.
authors.affiliation: Department of Histology, Graduate School of Medical Sciences, Kumamoto University, Honjo, Kumamoto, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Imamura
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yasuda
authors.forename: Brigitte
authors.initials: B
authors.lastname: Riwar
authors.forename: Seiji
authors.initials: S
authors.lastname: Inui
authors.forename: Shigeo
authors.initials: S
authors.lastname: Ekino
mesh_terms: D000818:Animals; D016175:B-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism; D002454:Cell Differentiation / Q000276:immunology*; D002645:Chickens / Q000276:immunology; D018858:Germinal Center / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D017578:Immunoglobulin Class Switching; D007136:Immunoglobulins / Q000276:immunology / Q000378:metabolism; D010950:Plasma Cells / Q000276:immunology / Q000378:metabolism; D013154:Spleen / Q000276:immunology / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism
chemical_list: D007136:Immunoglobulins