The serotonin transporter protein is expressed in psoriasis, where it may play a role in regulating apoptosis.
Since the symptoms of psoriasis may be changed by treatment with selective serotonin reuptake inhibitors (SSRIs), the expression of serotonin (5-HT) and its transporter protein (SERT) in the skin of patients with psoriasis were examined employing a biotinylated-streptavidine procedure. In biopsies of such skin staining for 5-HT was limited to platelets; the expression of SERT in the keratinocytes of involved regions was redistributed; the numbers of SERT-positive dendritic or round mononuclear cells in the epidermis of involved psoriatic skin were higher than in normal healthy control skin; and the dermis of the involved skin contained higher numbers of round inflammatory cells immunostained for SERT than either non-involved psoriatic skin or normal skin. Double-immunostaining indicated that the skin cells expressing SERT also expressed CD1a, CD3 or tryptase. In addition, SERT immunostaining was co localized with caspase-3, a key regulator of apoptosis, but not with TUNEL staining. The present findings indicate that SERT might play a role in regulating apoptosis in inflammatory cells associated with psoriasis, in which case this protein might constitute a valuable therapeutic target.
Thorslund
Kristofer
K
Unit of Dermatology and Venereology, Department of Medicine, Karolinska University Hospital, Solna, Stockholm 171 76, Sweden. kristofer.thorslund@karolinska.se
El-Nour
Husameldin
H
Nordlind
Klas
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018949:Antigens, CD1; D017209:Apoptosis / Q000276:immunology; D001792:Blood Platelets / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D017252:CD3 Complex; D053148:Caspase 3 / Q000276:immunology / Q000378:metabolism; D020405:Dermis / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D004817:Epidermis / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D015603:Keratinocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D007801:Langerhans Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D012701:Serotonin / Q000276:immunology / Q000378:metabolism*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000276:immunology / Q000378:metabolism*
D018949:Antigens, CD1; C419393:CD1a antigen; D017252:CD3 Complex; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D012701:Serotonin; D053148:Caspase 3