title: Serotonergic mechanisms in human allergic contact dermatitis.
abstract: 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.
authors.affiliation: Unit of Dermatology and Venereology, Department of Medicine, Karolinska Hospital, Solna, Stockholm, Sweden. Husameldin.elnour@ki.se
authors.forename: Husameldin
authors.initials: H
authors.lastname: El-Nour
authors.forename: Lena
authors.initials: L
authors.lastname: Lundeberg
authors.forename: Nada
authors.initials: N
authors.lastname: Abdel-Magid
authors.forename: Sol-Britt
authors.initials: SB
authors.lastname: Lonne-Rahm
authors.forename: Efrain C
authors.initials: EC
authors.lastname: Azmitia
authors.forename: Klas
authors.initials: K
authors.lastname: Nordlind
mesh_terms: D000662:Amphetamines / Q000494:pharmacology; D001792:Blood Platelets / Q000378:metabolism; D002460:Cell Line; D049109:Cell Proliferation; D015283:Citalopram / Q000494:pharmacology; D017449:Dermatitis, Allergic Contact / Q000276:immunology / Q000378:metabolism*; D005473:Fluoxetine / Q000494:pharmacology; D006801:Humans; D007150:Immunohistochemistry; D053583:Interleukin-1beta / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D007509:Irritants / Q000009:adverse effects; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D009532:Nickel / Q000009:adverse effects; D044282:Receptor, Serotonin, 5-HT1A / Q000378:metabolism*; D044402:Receptor, Serotonin, 5-HT2A / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology
chemical_list: D000662:Amphetamines; D015283:Citalopram; D005473:Fluoxetine; D053583:Interleukin-1beta; D007376:Interleukin-2; D007509:Irritants; D009532:Nickel; D044282:Receptor, Serotonin, 5-HT1A; D044402:Receptor, Serotonin, 5-HT2A; D012701:Serotonin; D050486:Serotonin Plasma Membrane Transport Proteins; D017366:Serotonin Receptor Agonists; D017367:Selective Serotonin Reuptake Inhibitors; C029938:nickel sulfate; C015952:4-iodo-2,5-dimethoxyphenylisopropylamine