IL-4 expression by neutrophils in psoriasis lesional skin upon high-dose UVB exposure.
BACKGROUND
Upon a single high dose of UVB irradiation of psoriatic lesional skin, IFN-gamma expression is decreased, whereas IL-4 expression is enhanced. A similar type 1 to type 2 shift was found in dermal T cells derived from irradiated lesional skin as compared to unexposed lesional psoriatic skin. We have found recently that the IL-4 protein detected in situ upon UVB exposure of normal skin was not associated with T cells but with infiltrating neutrophils.


OBJECTIVE
To determine which cell types express IL-4 in psoriatic skin after UVB irradiation.


METHODS
Skin biopsies were obtained from healthy controls and psoriasis patients before and after local UVB exposure. Double immunohistochemical stainings were performed to determine the identity of IL-4-expressing cells.


RESULTS
In the irradiated skin of both healthy controls and patients, IL-4-positive cells coexpressed elastase and CD15, but not CD3.


CONCLUSIONS
IL-4-expressing cells found in psoriatic skin after a single high-dose UVB exposure appeared to be neutrophils.
Piskin
Gamze
G
Department of Dermatology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. g.piskin@amc.uva.nl
Tursen
Umit
U
Bos
Jan D
JD
Teunissen
Marcel B M
MB
D000328:Adult; D015415:Biomarkers / Q000032:analysis; D001707:Biopsy, Needle; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D015847:Interleukin-4 / Q000032:analysis* / Q000528:radiation effects; D008297:Male; D008875:Middle Aged; D020556:Neutrophil Infiltration / Q000528:radiation effects*; D011565:Psoriasis / Q000473:pathology* / Q000532:radiotherapy*; D011829:Radiation Dosage; D012016:Reference Values; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D014467:Ultraviolet Therapy / Q000379:methods*
D015415:Biomarkers; D015847:Interleukin-4