Upregulation of ICOS on CD43+ CD4+ murine small intestinal intraepithelial lymphocytes during acute reovirus infection.
Murine intestinal intraepithelial lymphocytes (IELs) can be classified according to expression of a CD43 glycoform recognized by the S7 monoclonal antibody. In this study, we examined the response of S7+ and S7- IELs in mice during acute reovirus serotype 3 (Dearing strain) infection, which was confirmed by virus-specific real-time PCR. In vivo proliferation increased significantly for both S7- and S7+ IELs on day 4 post-infection as determined by BrdU incorporation; however, expression of the inducible costimulatory (ICOS) molecule, which peaked on day 7 post-infection, was upregulated on S7+ CD4+ T cells, most of which were CD4+8- IELs. In vitro ICOS stimulation by syngeneic peritoneal macrophages induced IFN-gamma secretion from IELs from day 7 infected mice, and was suppressed by treatment with anti-ICOS mAb. Additionally, IFN-gamma mRNA increased in CD4+ IELs on day 6 post-infection. These findings indicate that S7- and S7+ IELs are differentially mobilized during the immune response to reovirus infection; that the regulated expression of ICOS is associated with S7+ IELs; and that stimulation of IELs through ICOS enhances IFN-gamma synthesis during infection.
Montufar-Solis
Dina
D
Department of Diagnostic Sciences, Dental Branch, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
Garza
Tomas
T
Teng
Ba-Bie
BB
Klein
John R
JR
D000818:Animals; D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte / Q000378:metabolism*; D018122:B7-1 Antigen / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism*; D049109:Cell Proliferation; D004847:Epithelial Cells / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D005260:Female; D005434:Flow Cytometry; D060945:Inducible T-Cell Co-Stimulator Ligand; D060889:Inducible T-Cell Co-Stimulator Protein; D007371:Interferon-gamma / Q000096:biosynthesis; D007421:Intestine, Small / Q000166:cytology*; D017493:Leukocyte Common Antigens / Q000378:metabolism; D051917:Leukosialin / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D012088:Reoviridae Infections / Q000378:metabolism*; D015854:Up-Regulation / Q000235:genetics*
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D018122:B7-1 Antigen; C556694:Icos protein, mouse; D060945:Inducible T-Cell Co-Stimulator Ligand; D060889:Inducible T-Cell Co-Stimulator Protein; D051917:Leukosialin; D007371:Interferon-gamma; D017493:Leukocyte Common Antigens