Localization of IL-8 and complement components in lesional skin of psoriasis vulgaris and pustulosis palmaris et plantaris.
BACKGROUND
Munro's microabscesses are a characteristic histopathologic feature of psoriasis vulgaris; however, the pathomechanisms underlying the migration of transepidermal leukocytes (PMNs) have not been fully elucidated yet.


OBJECTIVE
Since the lesional scale extracts contain potent chemoattractants, such as IL-8 and C5a fragments, we studied their location in the lesions of psoriasis vulgaris and PPP with immunohistochemical techniques.


RESULTS
Localization of IL-8 was not detected in the subcorneal keratinocytes but was demonstrated only in the basal keratinocytes together with migrating PMNs. In contrast, the presence of a complement fragment, C3b, was observed on the cell membranes of subcorneal keratinocytes, suggesting that these were the sites of complement activation.


CONCLUSIONS
Such distinct localization of IL-8 and complement components suggests that the intraepidermal migration of PMNs takes place first according to the concentration gradient of IL-8, and thereafter they are guided by complement components to the final destination, the subcorneal portion of the lesional skin.
Ozawa
Maki
M
Department of Dermatology, Tohoku University Graduate School of Medicine, Sendai, Japan. ozawam@gonryo.med.tohoku.ac.jp
Terui
Tadashi
T
Tagami
Hachiro
H
D002465:Cell Movement / Q000276:immunology; D002630:Chemotactic Factors / Q000276:immunology; D015936:Complement C5a / Q000276:immunology*; D006801:Humans; D016209:Interleukin-8 / Q000276:immunology*; D015603:Keratinocytes / Q000276:immunology; D009504:Neutrophils / Q000276:immunology; D011565:Psoriasis / Q000276:immunology* / Q000503:physiopathology; D012867:Skin / Q000276:immunology*
D002630:Chemotactic Factors; D016209:Interleukin-8; D015936:Complement C5a