Epidermal CD8+ T cells reactive with group A streptococcal antigens in chronic plaque psoriasis.
Chronic plaque psoriasis is a T cell mediated disease associated with group A streptococci (GAS). We have previously shown the presence of a psoriasis-specific dermal Th1 subset that recognizes GAS antigens. To assess whether GAS-reactive T cells are also present in lesional epidermis, fresh cell suspensions or T cell lines isolated from lesional epidermis of 33 psoriasis patients were stained for intracellular interferon-gamma after stimulation with GAS antigens. The patients were typed by PCR for HLA-DR7 and HLA-Cw6 expression. A subset of GAS-reactive CD8+ T cells (2.4% +/- 2.4) was found in 14/21 (67%) fresh cell suspensions. A smaller subset of GAS-reactive CD4+ T cells (0.9% +/- 0.9) was found in 13/21 (62%) fresh cell suspensions, which was expanded in the T cell lines. There was a significant inverse correlation between the proportions of GAS-reactive CD4+ and CD8+ T cells in the fresh suspensions (r = -0.48, P = 0.0277). The presence of GAS-reactive CD4+ or CD8+ T cells did not correlate with HLA-DR7 or HLA-Cw6 expression, respectively. This study has demonstrated GAS-reactive CD8+, and to a lesser extent CD4+, T cell subsets in psoriatic epidermis and provides further evidence that GAS antigens may play a role in the pathogenesis of chronic plaque psoriasis.
Ovigne
J-M
JM
Dermatology Research, Faculty of Medicine, Imperial College of Science Technology and Medicine, St. Mary's campus, London, UK.
Baker
B S
BS
Davison
S C
SC
Powles
A V
AV
Fry
L
L
D000328:Adult; D000368:Aged; D017951:Antigen Presentation; D000942:Antigens, Bacterial / Q000008:administration & dosage; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D016022:Case-Control Studies; D002460:Cell Line; D005260:Female; D015236:HLA-C Antigens / Q000378:metabolism; D015809:HLA-DR7 Antigen / Q000378:metabolism; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011565:Psoriasis / Q000209:etiology / Q000276:immunology*; D012867:Skin / Q000276:immunology; D013297:Streptococcus pyogenes / Q000276:immunology* / Q000472:pathogenicity; D016176:T-Lymphocyte Subsets / Q000276:immunology
D000942:Antigens, Bacterial; D015236:HLA-C Antigens; C528994:HLA-C*06 antigen; D015809:HLA-DR7 Antigen; D007371:Interferon-gamma