Serotonergic mechanisms in human allergic contact dermatitis

• Published in: Acta dermato-venereologica Vol. 87; no. 5; pp. 390 - 396
• Main Authors: EL-NOUR, Husameldin, LUNDEBERG, Lena, ABDEL-MAGID, Nada, LONNE-RAHM, Sol-Britt, AZMITIA, Efrain C, NORDLIND, Klas
• Format: Journal Article
• Language: English
• Published: Uppsala Acta dermato-venereologica 2007
• Subjects: Amphetamines - pharmacology; Biological and medical sciences; Blood Platelets - metabolism; Cell Line; Cell Proliferation; Citalopram - pharmacology; Dermatitis, Allergic Contact - immunology; Dermatitis, Allergic Contact - metabolism; Dermatology; Fluoxetine - pharmacology; Humans; Immunohistochemistry; Interleukin-1beta - metabolism; Interleukin-2 - metabolism; Irritants - adverse effects; Leukocytes, Mononuclear - metabolism; Medical sciences; Medicin och hälsovetenskap; Nickel - adverse effects; Receptor, Serotonin, 5-HT1A - metabolism; Receptor, Serotonin, 5-HT2A - metabolism; Serotonin - metabolism; Serotonin Plasma Membrane Transport Proteins - metabolism; Serotonin Receptor Agonists - pharmacology; Serotonin Uptake Inhibitors - pharmacology; Human; Immunopathology; Allergy; Skin disease; serotonin receptors; Serotonin; Dermatology; allergic contact dermatitis; serotonin transporter protein; Mechanism; Contact dermatitis; Neurotransmitter; Carrier protein
• ISSN: 0001-5555; 1651-2057
• DOI: 10.2340/00015555-0288

Expression of serotonin (5-hydroxytryptamine; 5-HT), 5-HT receptors 1A (5-HT1AR) and 2A, and serotonin transporter protein (SERT) was studied in positive epicutaneous reactions to nickel sulphate in nickel-allergic patients, at 72 h post-challenge with the antigen. In addition, the effects of 5-HT2AR agonist 2,5-dimethoxy-4-iodoamphetamine (DOI), and the selective serotonin reuptake inhibitors (SSRIs) citalopram and fluoxetine, were tested on nickel-stimulated peripheral blood mononuclear cells from nickel-allergic patients, regarding their proliferation and interleukin (IL)-2 production, as well as the effect of these SSRIs on a murine Langerhans' cell-like line (XS52), regarding its IL-1beta production. Serotonin-positive platelets were increased in the inflamed skin compared with control skin. A decrease (p <0.01) in 5-HT1AR-positive mononuclear cells was evident in the eczematous skin compared with control skin, whereas 5-HT2AR- and SERT-positive cells were increased (p <0.001 for both) in the eczematous skin. Treatment of nickel-stimulated peripheral blood mononuclear cells with 5x10(-5) mol/l of DOI inhibited (p <0.01) the proliferation of nickel-stimulated peripheral blood mononuclear cells, while no effect was found regarding IL-2 production. Citalopram at 10(-6) mol/l tended to inhibit the production of IL-1beta by the XS52 cell line. These results indicate the implication of the serotonergic system in the contact allergic reaction.