Elevated serum L-selectin levels and abnormal regulation of L-selectin expression on leukocytes in atopic dermatitis: soluble L-selectin levels indicate disease severity.
BACKGROUND
L-selectin mediates leukocyte rolling on endothelium at sites of inflammation, suggesting that L-selectin may be involved in the development of cutaneous lesions of atopic dermatitis (AD). After leukocyte activation, L-selectin is rapidly shed from the cell surface.


OBJECTIVE
The purpose of this study was to assess leukocyte L-selectin expression and quantitate levels of serum soluble L-selectin (sL-selectin) in patients with AD.


METHODS
Serum sL-selectin levels in patients with AD (n = 70), contact dermatitis (n = 18), and psoriasis (n = 23), as well as normal control subjects (n = 30), were examined by using an ELISA. The L-selectin expression on leukocytes in heparinized blood samples from patients with AD (n = 18) and normal control subjects (n = 10) was also examined by flow cytometry.


RESULTS
Serum levels of sL-selectin in patients with AD were significantly higher than those found in normal control subjects. Furthermore, sL-selectin levels correlated positively with disease severity and total serum IgE levels in AD. The expression of L-selectin on B cells, monocytes, and neutrophils was significantly decreased in patients with AD compared with normal control subjects, although those on CD4(+) or CD8(+) T cells from patients with AD were similar to those from normal control subjects.


CONCLUSIONS
Elevated sL-selectin levels and the abnormal expression of L-selectin on some leukocyte subsets in patients with AD may correlate with inflammation associated with AD. Furthermore, the level of sL-selectin may be a useful immunologic indicator for disease activity in AD.
Department of Dermatology, Kanazawa University School of Medicine, Kanazawa, Japan.
Y
Y
Shimada
S
S
Sato
M
M
Hasegawa
T F
TF
Tedder
K
K
Takehara
D000293:Adolescent; D000328:Adult; D018951:Antigens, CD20 / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000737:chemistry; D018414:CD8-Positive T-Lymphocytes / Q000737:chemistry; D002648:Child; D002675:Child, Preschool; D003876:Dermatitis, Atopic / Q000097:blood*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology; D019041:L-Selectin / Q000097:blood*; D007962:Leukocytes / Q000737:chemistry*; D018950:Lipopolysaccharide Receptors / Q000032:analysis; D008297:Male; D009000:Monocytes / Q000276:immunology; D017452:Receptors, IgG / Q000097:blood; D012720:Severity of Illness Index; D012995:Solubility
D018951:Antigens, CD20; D018950:Lipopolysaccharide Receptors; D017452:Receptors, IgG; D019041:L-Selectin