Laberge S, Ghaffar O, Boguniewicz M, Center D M, Leung D Y, Hamid Q
Meakins-Christie Laboratories, Royal Victoria Hospital, McGill University, Montreal, Quebec, Canada.
J Allergy Clin Immunol. 1998 Oct;102(4 Pt 1):645-50. doi: 10.1016/s0091-6749(98)70282-9.
The mechanisms involved in the initiation and the maintenance of skin inflammation in atopic dermatitis (AD) are poorly understood. Previous studies have demonstrated increased numbers of infiltrating CD4+ T cells in acute lesions compared with normal control skin. IL-16 is a cytokine that has selective chemotactic activity for CD4+ cells.
We sought to examine whether IL-16 expression might be upregulated in acute versus chronic AD.
We investigated the expression of IL-16 mRNA in skin biopsy specimens from acute and chronic skin lesions, as well as from the uninvolved skin of patients with AD and normal skin. Cryostat sections from 4% paraformaldehyde-fixed skin biopsy specimens were processed for in situ hybridization by using cRNA coding for IL-16 mRNA. Numbers of infiltrating CD4+ and CD8+ cells were also determined by immunocytochemistry.
There were positive signals for IL-16 mRNA both in the basal layer of the epidermis and in the dermis of AD skin biopsy specimens from all subjects studied. The numbers of epidermal and dermal IL-16 mRNA+ cells were significantly increased in acute skin lesions compared with chronic (P <.01) and uninvolved (P <.001) skin lesions and compared with normal skin (P <.001). The number of CD4+ cells was significantly increased in acute skin lesions compared with chronic (P <.01) skin lesions and uninvolved skin (P <.01) and compared with normal skin (P <.01). Significant correlations were found between the numbers of CD4+ cells and the numbers of epidermal (r = 0.82, P <.001) and dermal (r = 0.71, P <.001) IL-16 mRNA+ cells.
The results demonstrate that upregulation of IL-16 mRNA expression in acute AD is associated with increased numbers of CD4+ cells, suggesting that IL-16 may play a role in the initiation of skin inflammation, presumably through recruitment of CD4+ cells.
特应性皮炎（AD）中皮肤炎症起始和维持所涉及的机制尚不清楚。既往研究表明，与正常对照皮肤相比，急性皮损中浸润的CD4 + T细胞数量增加。白细胞介素-16（IL-16）是一种对CD4 +细胞具有选择性趋化活性的细胞因子。
我们试图研究急性AD与慢性AD相比，IL-16表达是否上调。
我们调查了急性和慢性皮肤病变以及AD患者非病变皮肤和正常皮肤的皮肤活检标本中IL-16 mRNA的表达。使用编码IL-16 mRNA的cRNA对4％多聚甲醛固定的皮肤活检标本的低温切片进行原位杂交处理。还通过免疫细胞化学确定浸润的CD4 +和CD8 +细胞数量。
在所有研究对象的AD皮肤活检标本的表皮基底层和真皮层中均存在IL-16 mRNA的阳性信号。与慢性皮肤病变（P <.01）和非病变皮肤（P <.001）相比，以及与正常皮肤（P <.001）相比，急性皮肤病变中表皮和真皮IL-16 mRNA +细胞的数量显著增加。与慢性皮肤病变（P <.01）、非病变皮肤（P <.01）相比，以及与正常皮肤（P <.01）相比，急性皮肤病变中CD4 +细胞的数量显著增加。CD4 +细胞数量与表皮（r = 0.82，P <.001）和真皮（r = 0.71，P <.
