title: Differential susceptibility to staphylococcal superantigen (SsAg)-induced apoptosis of CD4+ T cells from atopic dermatitis patients and healthy subjects: the inhibitory effect of IL-4 on SsAg-induced apoptosis.
abstract: This study had two aims: 1) to determine whether there are differences between atopic dermatitis (AD) patients and healthy subjects in staphylococcal superantigen (SsAg)-induced CD4(+) T cell activation, cytokine production, chemokine receptor expression, and apoptosis; and 2) to investigate the effect of IL-4 on SsAg-induced apoptosis. By using immunofluorescence and annexin V staining, we analyzed PBMC with or without staphylococcal enterotoxin B (SEB) stimulation in the presence or absence of rIL-4 or anti-IL-4-neutralizing Abs in 15 healthy subjects and 27 AD patients. We found that SEB preferentially induced production of Th1 cytokine in SEB-reactive (TCRVbeta3(+) or Vbeta12(+) or Vbeta17(+)) CD4(+) T cells from healthy subjects and Th2 cytokine in those from AD patients. SEB induced up-regulation of CXCR3(+) cells in SEB-reactive CD4(+) T cells from healthy subjects and CCR4(+) cells in those from AD patients. SEB-reactive CD4(+) T cells from AD patients were more resistant to SEB-induced apoptosis than those from healthy subjects. There was no significant difference between AD and healthy subjects in SEB-induced activation of CD4(+) T cells. CXCR3(+) CD4(+) T cells were more susceptible to SEB-induced apoptosis than CCR4(+) CD4(+) T cells in healthy subjects. Exogenously added IL-4 inhibited SEB-induced apoptosis of SEB-reactive CD4(+) and CXCR3(+) CD4(+) T cells but not of CCR4(+) CD4(+) T cells in healthy subjects. Inhibition of endogenous IL-4 increased SEB-induced apoptosis of SEB-reactive CD4(+) T cells from AD patients. These results might provide new clues to the mechanism that SsAgs contribute to the persistence and exacerbation of allergic skin inflammation in AD.
authors.affiliation: Department of Pediatrics, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Yu-Tsan
authors.initials: YT
authors.lastname: Lin
authors.forename: Chen-Ti
authors.initials: CT
authors.lastname: Wang
authors.forename: Chen-Tong
authors.initials: CT
authors.lastname: Hsu
authors.forename: Li-Fang
authors.initials: LF
authors.lastname: Wang
authors.forename: Wen-Yi
authors.initials: WY
authors.lastname: Shau
authors.forename: Yao-Hsu
authors.initials: YH
authors.lastname: Yang
authors.forename: Bor-Luen
authors.initials: BL
authors.lastname: Chiang
mesh_terms: D000293:Adolescent; D000328:Adult; D000918:Antibody Specificity; D017209:Apoptosis / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000382:microbiology; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis; D003876:Dermatitis, Atopic / Q000276:immunology* / Q000473:pathology; D004768:Enterotoxins / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007113:Immunity, Innate; D007073:Immunoglobulin E / Q000096:biosynthesis / Q000097:blood; D015847:Interleukin-4 / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D008213:Lymphocyte Activation; D008297:Male; D054398:Receptors, CCR4; D054367:Receptors, CXCR3; D019707:Receptors, Chemokine / Q000096:biosynthesis; D013211:Staphylococcus aureus / Q000276:immunology*; D018089:Superantigens / Q000494:pharmacology*; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D015854:Up-Regulation / Q000276:immunology
chemical_list: C515354:CCR4 protein, human; C515187:CXCR3 protein, human; D016207:Cytokines; D004768:Enterotoxins; D054398:Receptors, CCR4; D054367:Receptors, CXCR3; D019707:Receptors, Chemokine; D018089:Superantigens; D015847:Interleukin-4; D007073:Immunoglobulin E; C031818:enterotoxin B, staphylococcal