title: Expression of dipeptidyl-peptidase IV (CD26) on CD8+ T cells is significantly decreased in patients with psoriasis vulgaris and atopic dermatitis.
abstract: T cells play a major role in inflammatory skin disorders such as psoriasis vulgaris and atopic dermatitis. They are both active on the level of cell-to-cell interaction and by the secretion of pro-inflammatory mediators. CD26 is a lymphocyte membrane-associated dipeptidyl peptidase IV (DPP IV), which is able to inactivate chemokines such as RANTES or eotaxin by cleaving dipeptides from the NH2-terminus of proteins. We investigated the expression of CD26 on CD4+ and CD8+ peripheral blood T cells in patients with psoriasis and atopic dermatitis. In addition PASI and SCORAD as a measure of disease severity were determined in each patient at the time of blood drawing. Thirty patients with psoriasis, 15 with atopic dermatitis and 17 age- and sex-matched healthy persons were investigated by two-colour flow cytometry using epitope-specific monoclonal antibodies. Our results revealed, that there is a significant decrease (P<0.05) of CD26 expression on CD8+ T cells in both psoriasis (7.7%+/-3.3, mean and SD, n=30) and atopic dermatitis patients (7.9%+/-3.7, mean and SD, n=15) compared to the control population (11.58%+/-5.0, mean and SD, n=17). However, there was no correlation to disease severity as determined by PASI and SCORAD, respectively. Since CD26 can be regarded as an anti-inflammatory principle the decreased expression in psoriasis and atopic dermatitis patients may lead to a dysbalance in favour of pro-inflammatory mediators in both clinical conditions.
authors.affiliation: Department of Dermatology, Christian-Albrechts-University of Kiel, Schittenhelmstrasse 7, D-24105 Kiel, Germany. obock@dermatology.uni-kiel.de
authors.forename: O
authors.initials: O
authors.lastname: Bock
authors.forename: I
authors.initials: I
authors.lastname: Kreiselmeyer
authors.forename: U
authors.initials: U
authors.lastname: Mrowietz
mesh_terms: D000293:Adolescent; D000328:Adult; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism* / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D003876:Dermatitis, Atopic / Q000378:metabolism* / Q000503:physiopathology; D018819:Dipeptidyl Peptidase 4 / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000378:metabolism* / Q000503:physiopathology; D012720:Severity of Illness Index
chemical_list: D018819:Dipeptidyl Peptidase 4