title: Epidermal cis-urocanic acid levels correlate with lower specific cellular immune responses after hepatitis B vaccination of ultraviolet B-exposed humans.
abstract: Urocanic acid (UCA) is a major UV-absorbing chromophore in the epidermis and has been suggested to act as one of the initiators of UV-induced immunosuppression. cis-UCA, the isomer from UCA that is formed upon UV exposure, has been shown to impair some cellular immune responses. cis-UCA levels were determined in a study in which the influence of ultraviolet B (UVB) exposure on immune responses after hepatitis B vaccination in human volunteers was established. A significant increase in cis-UCA levels was found in the skin of UVB-exposed volunteers compared with controls. cis-UCA levels, calculated as the percentage of the total UCA amount, in UVB-exposed volunteers correlated significantly with the cumulative UVB dose received in 5 consecutive days, i.e. the higher the UVB dose (J/m2), the higher the cis-UCA levels (until a cis-UCA plateau was reached in the so-called photostationary state). Correlations between skin cis-UCA levels and immune responses were determined, and they revealed no statistically significant correlations among lymphocyte proliferation responses after either mitogenic stimulation or stimulation with recall antigens. No correlation was found between cis-UCA levels and hepatitis B-specific antibody titers. However, we found a statistically significant negative correlation between cis-UCA levels and hepatitis B-specific lymphocyte proliferation responses when volunteers were irradiated with UVB before hepatitis B vaccination. In other words, volunteers with high cis-UCA levels caused by UVB exposure showed lower cellular immune responses against hepatitis B antigen after hepatitis B vaccination.
authors.affiliation: Laboratory for Pathology and Immunobiology, National Institute of Public Health and the Environment, Bilthoven, The Netherlands. annemarie.sleijffers@rivm.nl
authors.forename: Annemarie
authors.initials: A
authors.lastname: Sleijffers
authors.forename: Arthur
authors.initials: A
authors.lastname: Kammeyer
authors.forename: Frank R
authors.initials: FR
authors.lastname: de Gruijl
authors.forename: Greet J
authors.initials: GJ
authors.lastname: Boland
authors.forename: Jan
authors.initials: J
authors.lastname: van Hattum
authors.forename: Willem A
authors.initials: WA
authors.lastname: van Vloten
authors.forename: Henk
authors.initials: H
authors.lastname: van Loveren
authors.forename: Marcel B M
authors.initials: MB
authors.lastname: Teunissen
authors.forename: Johan
authors.initials: J
authors.lastname: Garssen
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D017325:Hepatitis B Vaccines / Q000008:administration & dosage; D006801:Humans; D007108:Immune Tolerance / Q000528:radiation effects; D007111:Immunity, Cellular / Q000528:radiation effects; D018462:Photobiology; D012867:Skin / Q000276:immunology / Q000378:metabolism / Q000528:radiation effects*; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014560:Urocanic Acid / Q000378:metabolism; D014614:Vaccines, Synthetic / Q000008:administration & dosage
chemical_list: C075654:Engerix-B; D017325:Hepatitis B Vaccines; D014614:Vaccines, Synthetic; D014560:Urocanic Acid