Adhesion molecule profiles in atopic dermatitis vs. allergic contact dermatitis: pharmacological modulation by cetirizine.
BACKGROUND
Experimental data suggest that there is an imbalance between Th1 and Th2 cells in atopic dermatitis (AD) skin compared to allergic contact dermatitis (ACD). This imbalance (Th2 and Th1 predominance, respectively) implies the production of different cytokines in these two conditions leading to different expression of adhesion molecules on skin endothelial cells.


OBJECTIVE
The expression of VCAM-1 (IL-4/Th2-dependent) and ICAM-1 (INF-gamma/IL-1) on dermal vessels was compared in six patients with AD and six patients with ACD. The effect of cetirizine, a highly selective H1-receptor antagonist on the expressions was studied.


METHODS
Six patients with AD were challenged with Dermatophagoides pteronyssimus (DPT patch tests applied to clinically normal skin) and six patients with ACD challenged in the same way with allergens of the European standard series. Skin biopsies at challenged sites were performed before and 6, 24 and 48 h after challenge. The experiment was carried out under double-blind cross-over conditions during a 4-day treatment with a placebo and cetirizine.


RESULTS
In AD patients, the scores for both VCAM-1 and ICAM-1 were high before and after challenge. In ACD patients, the ICAM-1 score was high at each experimental time, but the VCAM-1 score, which was significantly lower before challenge, increased at 6, 24 and 48 h after challenge. The administration of cetirizine significantly reduced the VCAM-1 expression in AD patients at each experimental time.


CONCLUSIONS
It is concluded that the increased VCAM-1 expression in AD patients compared to ACD may reflect greater IL-4 and/or IL-13 production in situ. The study also confirms the existence of a modulating effect of cetirizine in vivo on adhesion molecule expression.
Boone
M
M
Department of Dermatology, University Hospital Brugmann, Brussels, Belgium. dr.boone@pi.be
Lespagnard
L
L
Renard
N
N
Song
M
M
Rihoux
J P
JP
D000328:Adult; D018926:Anti-Allergic Agents / Q000494:pharmacology*; D001706:Biopsy; D017332:Cetirizine / Q000494:pharmacology*; D018592:Cross-Over Studies; D017449:Dermatitis, Allergic Contact / Q000378:metabolism*; D003876:Dermatitis, Atopic / Q000378:metabolism*; D004311:Double-Blind Method; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000187:drug effects* / Q000378:metabolism*; D019010:Vascular Cell Adhesion Molecule-1 / Q000187:drug effects* / Q000378:metabolism*
D018926:Anti-Allergic Agents; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D017332:Cetirizine