title: Increased interleukin-7 levels in the sera of psoriatic patients: lack of correlations with interleukin-6 levels and disease intensity.
abstract: Interleukin (IL)-7 is a multifunctional cytokine which is involved in the regulation of keratinocyte-T lymphocyte interactions; the latter is an important factor in the pathogenesis of psoriasis. In vitro, IL-7 is able to induce release of cytokines, including IL-6; IL-6 expression is known to be enhanced in psoriatic patients. Serum levels of IL-7 and IL-6 were measured by ELISA in 40 psoriatic patients and compared with cytokine levels in 18 healthy individuals. Serum levels of IL-7 were also evaluated in 24 psoriatic patients during the remission of the disease after effective treatment. The IL-7 and IL-6 serum levels were significantly higher in psoriatic patients than in healthy subjects and the IL-7 serum levels did not significantly decrease after treatment. Serum levels of IL-7 did not correlate with PASI scores; however, a significant positive relationship was observed between IL-6 levels and PASI scores. There was no correlation between increased levels of IL-7 and IL-6 in the sera of psoriatic patients, suggesting the lack of a direct link between these two cytokines in the psoriatic process. In conclusion, increased IL-7 serum levels suggest that IL-7, like IL-6, may be involved in the pathogenesis of psoriasis, but in contrast with IL-6, serum IL-7 levels could not be used as a marker of disease activity in psoriatic patients.
authors.affiliation: Department of Dermatology, University of Medicine, Wroclaw, Poland. jszepiet@derm.am.wroc.pl
authors.forename: J C
authors.initials: JC
authors.lastname: Szepietowski
authors.forename: E
authors.initials: E
authors.lastname: Bielicka
authors.forename: P
authors.initials: P
authors.lastname: Nockowski
authors.forename: A
authors.initials: A
authors.lastname: Noworolska
authors.forename: F
authors.initials: F
authors.lastname: Wasik
mesh_terms: D000287:Administration, Topical; D000293:Adolescent; D000328:Adult; D000368:Aged; D000875:Anthralin / Q000627:therapeutic use; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D015851:Interleukin-7 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011701:PUVA Therapy / Q000379:methods; D011565:Psoriasis / Q000097:blood* / Q000188:drug therapy
chemical_list: D000893:Anti-Inflammatory Agents; D015850:Interleukin-6; D015851:Interleukin-7; D000875:Anthralin