title: Colocalization of somatostatin- and HLA-DR-like immunoreactivity in dendritic cells of psoriatic skin.
abstract: This study presents an immunohistochemical characterization of somatostatin-positive dendritic cells in psoriatic lesions. Somatostatin is a neuropeptide with inhibitory action on several neuropeptides and hormones, but also with immunomodulating properties, and has been used in several studies as treatment for psoriasis. The number of somatostatin-positive dendritic cells was found to be larger in psoriatic lesions than in normal skin of psoriasis patients and healthy controls. Colocalization of somatostatin and HLA-DR immunoreactivity was demonstrated in a subgroup of dendritic cells of psoriatic skin, whereas double-labelled cells were not found in uninvolved skin. The somatostatin-positive cells in the epidermis and dermis did not co-express CD1a, CD35, CD45RB, CD45RO, CD68, factor XIIIa or S-100. On the basis of these findings, the somatostatin-positive cells seem to represent a specific population of dermal dendritic cells, distinct from Langerhans' cells and factor XIIIa-positive cells, which are found in elevated amounts in chronic plaque psoriasis.
authors.affiliation: Department of Dermatology, Huddinge University Hospital, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Talme
authors.forename: M
authors.initials: M
authors.lastname: Schultzberg
authors.forename: K G
authors.initials: KG
authors.lastname: Sundqvist
authors.forename: J A
authors.initials: JA
authors.lastname: Marcusson
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001706:Biopsy / Q000379:methods; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000737:chemistry*; D004311:Double-Blind Method; D005260:Female; D006684:HLA-DR Antigens / Q000032:analysis*; D006727:Hormone Antagonists / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000473:pathology*; D012867:Skin / Q000737:chemistry*; D013004:Somatostatin / Q000032:analysis*
chemical_list: D006684:HLA-DR Antigens; D006727:Hormone Antagonists; D013004:Somatostatin