title: Increased expression of plasma and CD4+ T lymphocyte costimulatory molecule CD26 in adult patients with allergic asthma.
abstract: CD26, which is a costimulatory molecule and peptidase, is responsible for the degradation of interferon (IFN)-gamma-induced chemokines. To elucidate the immunopathological role of CD26 in allergic asthma, we investigated plasma soluble CD26 (sCD26) concentration and its cell surface expression on lymphocytes, monocytes, CD4+ T helper, CD8+ T suppressor plus cytotoxic T, invariant natural killer T (iNKT), and CD19+ B lymphocytes in allergic asthmatic patients. Plasma sCD26 was significantly elevated in asthmatic patients regardless of inhaled corticosteroid treatment (all P < 0.05). Cell surface expression of CD26 was significantly up-regulated on lymphocytes, especially on CD4+ and iNKT lymphocytes (all P < 0.05), but not on other cell types. Significant positive correlations were found between sCD26 and the percentage of eosinophils, Th2-related chemokines CCL5 and CCL22, and costimulatory molecule sCTLA-4 (all P < 0.05). In conclusion, the aberrant expression of CD26 may contribute to the inflammatory process and Th2 predominance in the immunopathogenesis of allergic asthma.
authors.affiliation: Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
authors.forename: Samantha W M
authors.initials: SW
authors.lastname: Lun
authors.forename: C K
authors.initials: CK
authors.lastname: Wong
authors.forename: Fanny W S
authors.initials: FW
authors.lastname: Ko
authors.forename: David S C
authors.initials: DS
authors.lastname: Hui
authors.forename: Christopher W K
authors.initials: CW
authors.lastname: Lam
mesh_terms: D000328:Adult; D000368:Aged; D001249:Asthma / Q000097:blood / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002681:China; D018819:Dipeptidyl Peptidase 4 / Q000097:blood / Q000378:metabolism*; D005260:Female; D006801:Humans; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D015854:Up-Regulation
chemical_list: D018819:Dipeptidyl Peptidase 4