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.
['Potockova|Hana|H|', 'Sinkorova|Jana|J|', 'Karova|Kristyna|K|', 'Sinkora|Marek|M|']
D000818:Animals D015703:Antigens, CD D016175:B-Lymphocyte Subsets D001402:B-Lymphocytes D001419:Bacteria D005856:Germ-Free Life D007082:Ileum D017578:Immunoglobulin Class Switching D007156:Immunologic Memory D016130:Immunophenotyping D008213:Lymphocyte Activation D064307:Microbiota D016693:Receptors, Antigen, T-Cell, alpha-beta D016692:Receptors, Antigen, T-Cell, gamma-delta D034421:Sus scrofa D013602:T-Lymphocytes, Cytotoxic D006377:T-Lymphocytes, Helper-Inducer
Differentiation Cell surface molecules Gut development Lymphocyte subpopulations Mucosal immunity Porcine immune system