The distribution of lymphoid cells in the small intestine of germ-free and conventional piglets.
Porcine ileum is populated with a high proportion of B cells but previous studies have shown that they are not developed there. While B cells prevail in the ileum even in germ-free animals, microbial colonization is a major factor that causes even a greater prevalence of B cells in the ileum and further differential representation of lymphoid cells throughout small intestine. Analysis of lymphoid subpopulations showed that the effector cells appear only after colonization. These include class-switched IgM(+)IgA(+) B cells, primed CD2(-)CD21(+) B cells, antibody-producing/memory CD2(+)CD21(-) B cells, and effector/memory CD4(+)CD8(+) αβ Th cells. While colonization resulted in a uniform distribution of effector cells throughout the gut, it caused a decrease in the frequency of cytotoxic αβ and CD2(+)CD8(+) γδ T cells. These results suggest that the ileum is a site where naive B cells expand presumably to increase antibody repertoire but the entire small intestine is immunofunctionally comparable.
Laboratory of Gnotobiology, Institute of Microbiology of the Czech Academy of Sciences, v.v.i., Novy Hradek 54922, Czech Republic.
Hana
H
Potockova
Laboratory of Gnotobiology, Institute of Microbiology of the Czech Academy of Sciences, v.v.i., Novy Hradek 54922, Czech Republic.
Jana
J
Sinkorova
Laboratory of Gnotobiology, Institute of Microbiology of the Czech Academy of Sciences, v.v.i., Novy Hradek 54922, Czech Republic.
Kristyna
K
Karova
Laboratory of Gnotobiology, Institute of Microbiology of the Czech Academy of Sciences, v.v.i., Novy Hradek 54922, Czech Republic. Electronic address: Marek.Sinkora@worldonline.cz.
Marek
M
Sinkora
D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D016175:B-Lymphocyte Subsets / Q000276:immunology* / Q000382:microbiology; D001402:B-Lymphocytes / Q000276:immunology* / Q000382:microbiology; D001419:Bacteria / Q000254:growth & development / Q000276:immunology; D005856:Germ-Free Life / Q000276:immunology; D007082:Ileum / Q000276:immunology* / Q000382:microbiology; D017578:Immunoglobulin Class Switching; D007156:Immunologic Memory; D016130:Immunophenotyping; D008213:Lymphocyte Activation; D064307:Microbiota / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000378:metabolism; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000378:metabolism*; D034421:Sus scrofa / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000382:microbiology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology* / Q000382:microbiology
D015703:Antigens, CD; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta
Cell surface molecules; Differentiation; Gut development; Lymphocyte subpopulations; Mucosal immunity; Porcine immune system