Molleculor Biological Analysis of the role of B71BB1 in contact dermatitis

最近，已经在活化的B细胞上鉴定了另一种CD 28配体，CD 86（B70/B7-2）。还发现，CD 86可能在初级免疫应答中对T细胞的共刺激起重要作用（Nature：366，76 - 79，1993）。本实验首先用抗CD 80（L307）、抗CD 86（IT 2）单克隆抗体对体外培养的人皮肤EC表面CD 80、CD 86的表达进行了检测。角质形成细胞（KC）表面CD 80、CD 86分子表达较少，而郎格罕细胞（LC）表面CD 80、CD 86分子表达较强。CD 86和CD 86分子在接触性皮炎、特应性皮炎和银屑病中均被检测到。在这些情况下，主要诱导CD 86的表达。免疫印迹法检测IT 2是否与LC上70 KD糖蛋白发生反应。本实验还观察了抗CD_（80）和抗CD_（86）单克隆抗体对EC刺激异基因外周血单个核细胞（PBMC）增殖的影响。抗CD 80和抗CD 86单抗均能有效抑制混合表皮细胞-淋巴细胞反应，提示LC表面表达的CD 86（B70/B7-2）抗原可能在接触性皮炎这一原发性免疫反应中起重要的T细胞共刺激作用。

Recently, an alternative CD28 ligand, CD86 (B70/B7-2) has been identified on activated B cells. It has been also found that CD86 may play an important role for costimulation of T cells in a primary immune response (Nature : 366,76-79,1993). These finding led us to determine whether CD80 and CD86 antigens express on Langerhans cells (LC) and costimulatory molecules transduced signals play a role in T cell activation in contact hypersensitivity.We first examined CD80, CD86 expression on EC of organ cultured human skin, by staining with the monoclonal anti CD80 (L307), anti CD86Ab (IT2). Keratinocyte (KC) expressed little CD80, CD86, but both CD80 and CD86 molecules on Langerhans cell (LC) have been expressed extensively strongly after culturing. Both CD86 and CD 86 molecules have been detected in contact ddermatitis, atopic dermatitis and psoriasis. In these cases, expression of CD86 was predominantly induced. To determine whether IT2 react with 70KD glycoprotein on LC,immunoblotting method was conducted. IT2 was reacted mainly with the 70KD peptide of LC.We also examined the effect of mAb anti-CD80 or mAb anti-CD86 on the capacity of cultured EC to stimulate proliferation of allogeneic peripheral blood mononuclear cellc (PBMC). Both anti CD80 mAb and anti CD86 mAb efficiently inhibited the mixed epidermal cell-lymphocyte reaction.These data indicate that CD86 (B70/B7-2) antigen expressed on LC may play an important role for costimulation of T cells in a primary immune response ; contact dermatitis.