Accumulation of FITC near stratum corneum-visualizing epidermal distribution of a strong sensitizer using two-photon microscopy
Journal article, 2009
Background The allergenic potency of a hapten is related to its skin penetration properties, but little is known about the distribution of haptens in the skin following topical application. Objectives The aim of this study was to investigate the diffusion and epidermal distribution using two-photon microscopy (TPM) of two fluorescent compounds. Methods Sensitizing capacities of fluorescein isothiocyanate (FITC) and fluorescein were investigated using the local lymph node assay. Chemical reactivity of the compounds was analysed, and their distribution in human epidermis was visualized using TPM and confocal microscopy. Also the in vitro diffusion through epidermis of FITC and fluorescein has been examined. Results FITC was classified as an extreme sensitizer, whereas fluorescein was non-sensitizing. TPM and confocal microscopy showed an accumulation of FITC in stratum corneum (SC), whereas fluorescein was more evenly distributed in epidermis. The diffusion of fluorescein through epidermis was three times higher than that of FITC. Conclusions TPM, which has never been used in this context before, is a promising tool for visualizing the distribution of fluorescent compounds of varying reactivity in intact skin. The strong allergen FITC is mainly retained in or adjacent to SC, whereas most fluorescein diffused through the epidermis.
local lymph node assay
microscopy
peptide reactivity
fluorescein isothiocyanate
two-photon
laser scanning confocal
allergic contact-dermatitis
contact allergy
sensitization
microscopy
phenylisothiocyanate
skin penetration
classification
in-vitro
fluorescent hapten
skin
hypersensitivity
FITC
dinitrochlorobenzene
lymph-node assay
Author
Kristin Samuelsson
University of Gothenburg
Carl Simonsson
University of Gothenburg
Charlotte A Jonsson
University of Gothenburg
Gunnar Westman
Chalmers, Chemical and Biological Engineering, Organic Chemistry
Marica B Ericson
University of Gothenburg
Ann-Therese Karlberg
University of Gothenburg
Contact Dermatitis
0105-1873 (ISSN) 1600-0536 (eISSN)
Vol. 61 2 91-100Subject Categories
Chemical Sciences
Organic Chemistry
DOI
10.1111/j.1600-0536.2009.01591.x