title: Galectin-7, induced by cis-urocanic acid and ultraviolet B irradiation, down-modulates cytokine production by T lymphocytes.
abstract: Urocanic acid (UCA) is an epidermal chromophore that undergoes trans to cis isomerization after UVB irradiation. cis-UCA is a potent inhibitor of cutaneous acquired immunity. The aim of this study was to explore the genes, which are upregulated by cis-UCA in normal human epidermal keratinocytes (NHEK) and investigated its role in vitro using human T-lymphocyte cell line, Jurkat cells. DNA microarray analysis and real-time PCR investigation revealed that cis-UCA, not trans-UCA, increased the expression of a gene encoding a β-galactoside-binding lectin, galectin-7, LGALS7B. Immunohistochemical study demonstrated that galectin-7 was highly expressed in the epidermis in the patients with actinic keratosis. Galectin-7 administration upregulated apoptosis and inhibited the expression of interleukin-2 (IL2) and interferon-γ (IFNG) mRNA in Jurkat cells. Taken together, galectin-7 may play important roles in downregulating the functions of T lymphocytes after UVB irradiation and can be developed into novel immunosuppressive therapies for inflammatory skin diseases.
authors.affiliation: Department of Dermatology, University of Occupational and Environmental Health, Kitakyushu, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Kana
authors.initials: K
authors.lastname: Hiromasa
authors.forename: Rieko
authors.initials: R
authors.lastname: Kabashima-Kubo
authors.forename: Manabu
authors.initials: M
authors.lastname: Yoshioka
authors.forename: Motonobu
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis; D002241:Carbohydrates / Q000737:chemistry; D016022:Case-Control Studies; D002478:Cells, Cultured; D005260:Female; D037161:Galectins / Q000502:physiology*; D005786:Gene Expression Regulation; D006801:Humans; D007166:Immunosuppressive Agents / Q000737:chemistry; D007249:Inflammation; D007376:Interleukin-2 / Q000378:metabolism; D019169:Jurkat Cells; D055623:Keratosis, Actinic / Q000378:metabolism*; D008297:Male; D017434:Protein Structure, Tertiary; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000528:radiation effects; D014466:Ultraviolet Rays; D014560:Urocanic Acid / Q000737:chemistry*
chemical_list: D002241:Carbohydrates; D037161:Galectins; D007166:Immunosuppressive Agents; D007376:Interleukin-2; C092525:LGALS7 protein, human; D014560:Urocanic Acid
keywords: UVB; actinic keratosis; apoptosis; cis-urocanic acid; galectin-7