title: Increase of intestinal intraepithelial lymphocytes expressing CD8 antigen following challenge infection with Eimeria acervulina.
abstract: Eimerian infection-induced changes in the intestinal intraepithelial lymphocyte (IEL) subpopulations expressing CD8 antigen (cytotoxic/suppressor T cells) or antigen-specific T cell receptor (TCR) heterodimer alpha beta (TCR2) or gamma delta (TCR1) were investigated in F2 crosses of 15I5 B-congenic chickens differing for the major histocompatibility complex (MHC). Duodenum TCR2+ IEL were increased in B2 B2 and B5 B5 chickens 7 days following secondary infection. Two-color immunofluorescence revealed that the majority of CD8+ cells in the duodenum intraepithelium of immune chickens expressed TCR2. A significant increase in the duodenum TCR2+CD8+ and TCR1+CD8+ IEL occurred in B2 B2 chickens, which developed significantly less oocyst production than the B5 B5 chickens following challenge infection. The results suggest that a significant increase in the duodenum CD8+ IEL may reflect an enhanced acquired immunity of B2 B2 chickens.
authors.affiliation: Livestock and Poultry Sciences Institute, U.S. Department of Agriculture, Beltsville, Maryland 20705.
authors.forename: H S
authors.initials: HS
authors.lastname: Lillehoj
authors.forename: L D
authors.initials: LD
authors.lastname: Bacon
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D016827:CD8 Antigens; D002645:Chickens / Q000469:parasitology*; D003048:Coccidiosis / Q000276:immunology / Q000662:veterinary*; D004386:Duodenum / Q000276:immunology*; D004539:Eimeria / Q000276:immunology; D011201:Poultry Diseases / Q000276:immunology*; D013047:Specific Pathogen-Free Organisms; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D016827:CD8 Antigens