An immune response study of oakmoss absolute and its constituents atranol and chloroatranol.
BACKGROUND
Atranol and chloroatranol are the main allergens of oakmoss absolute. However, the immune responses induced by these substances are poorly characterized.


OBJECTIVE
To characterize immune responses induced by atranol, chloroatranol and oakmoss absolute in mice.


METHODS
Mice were sensitized and challenged with various concentrations of atranol, chloroatranol, and oakmoss absolute. The immune responses were analysed as B cell infiltration, T cell proliferation in the draining lymph nodes, and expression of interleukin (IL)-18, IL-1β and tumour necrosis factor-α in skin. The cytotoxicity of atranol and chloroatranol against keratinocytes was determined.


RESULTS
Sensitization experiments showed that atranol, chloroatranol and oakmoss induced sensitization when applied in high concentrations. Challenge experiments showed that even low concentrations of atranol and chloroatranol induced sensitization. In parallel, atranol and chloroatranol elicited challenge reactions following sensitization with oakmoss. The magnitude of the immune response to the three allergens increased in the following order: atranol, chloroatranol, and oakmoss. The expression of proinflammatory cytokines was induced by chloroatranol and oakmoss, but not by atranol. Chloroatranol was found to be more cytotoxic than atranol against keratinocytes.


CONCLUSIONS
Atranol and chloroatranol can elicit both sensitization and challenge reactions, but the mixture of allergens in oakmoss absolute is more potent than atranol and chloroatranol alone.
Department of International Health, Immunology and Microbiology, University of Copenhagen, DK-2200 Copenhagen, Denmark.
Charlotte Menné
CM
Bonefeld
Morten Milek
MM
Nielsen
Elena
E
Gimenéz-Arnau
Matthieu
M
Lang
Marie Torp
MT
Vennegaard
Carsten
C
Geisler
Jeanne Duus
JD
Johansen
Jean-Pierre
JP
Lepoittevin
D000818:Animals; D018941:Antigens, CD19 / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D001547:Benzaldehydes / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002460:Cell Line; D049109:Cell Proliferation; D017449:Dermatitis, Allergic Contact / Q000276:immunology*; D020382:Interleukin-18 / Q000276:immunology; D053583:Interleukin-1beta / Q000276:immunology; D015603:Keratinocytes; D051379:Mice; D008808:Mice, Inbred CBA; D010328:Patch Tests; D012116:Resins, Plant / Q000737:chemistry*; D013729:Terpenes / Q000737:chemistry* / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
D018941:Antigens, CD19; D001547:Benzaldehydes; D020382:Interleukin-18; D053583:Interleukin-1beta; D012116:Resins, Plant; D013729:Terpenes; D014409:Tumor Necrosis Factor-alpha; C493895:atranol; C487450:chloroatranol; C044724:oakmoss
atranol; chloroatranol; oakmoss