title: Differential requirement of CD28 costimulation for activation of murine CD8+ intestinal intraepithelial lymphocyte subsets and lymph node cells.
abstract: The CD8+CD4- (CD8+) murine small intestinal intraepithelial lymphocytes (IELs) contain two subpopulations, one expressing alpha alpha-CD8 homodimers and another alpha beta-CD8 heterodimers. In this study, plate-bound anti-TCR beta-chain (TCR-beta) mAb alone or combined with anti-CD28 mAb is used as a model system to study activation requirement of these two CD8+ IEL subsets. In contrast to CD8+ lymph node (LN) cells that require both TCR and CD28 triggering for activation, alpha beta-CD8+ IELs proliferate and produce IL-2 and IFN-gamma when stimulated with anti-TCR-beta mAb alone, and soluble CTLA-4 Ig has no effect on their responses. On the other hand, alpha alpha-CD8+ IELs neither make IL-2 or IFN-gamma nor proliferate even when both stimuli are provided. However, alpha alpha-CD8+ IELs are capable of proliferation in both CD8+ IEL subsets is lower than in CD8+ LN cells, which contributes to the weaker and delayed response of CD8+ IELs.
authors.affiliation: Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, 2epublic of China.
authors.forename: V
authors.initials: V
authors.lastname: Gelfanov
authors.forename: Y G
authors.initials: YG
authors.lastname: Lai
authors.forename: V
authors.initials: V
authors.lastname: Gelfanova
authors.forename: J Y
authors.initials: JY
authors.lastname: Dong
authors.forename: J P
authors.initials: JP
authors.lastname: Su
authors.forename: N S
authors.initials: NS
authors.lastname: Liao
mesh_terms: D000818:Animals; D018106:CD28 Antigens / Q000096:biosynthesis / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D005260:Female; D007371:Interferon-gamma / Q000032:analysis; D007376:Interleukin-2 / Q000032:analysis; D007413:Intestinal Mucosa / Q000166:cytology; D008198:Lymph Nodes / Q000166:cytology; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology; D015375:Receptors, Interleukin-2 / Q000502:physiology; D015398:Signal Transduction / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D018106:CD28 Antigens; D007376:Interleukin-2; D016693:Receptors, Antigen, T-Cell, alpha-beta; D015375:Receptors, Interleukin-2; D007371:Interferon-gamma