Analysis for a role of dectin-2 in ultraviolet-light-induced immune tolerance

Dectin-2在紫外线诱导的免疫耐受中的作用分析

• 批准号: 14370263
• 负责人: ARAGANE Yoshinori
• 金额: $ 4.35万
• 依托单位: Kinki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14370263/
• 关键词: ultraviolet B light; contact hypersensitivity; immune tolerance; regulatory T cells; トレランス; UVB; マウス; Dectin-2; 可溶性Dectin-2; 免疫調節型T細胞

It is known that ultraviolet B light(UV) impairs the induction phase of contact hypersensitivity responses(CHS) and subsequently induces tolerance. Although this phenomenon has been appreciated for decades to be a major biological importance, immunological mechanisms underlying this event are not completely clear yet Dectin-2 is a new member of c-type lectin, which is selectively expressed on epidermal langerhans cells(LC). Here we examined roles of dectin-2 in UVB-induced immune tolerance of CHS. To do so, we first generated a soluble form of dectin-2(sDec2). sDec2 was generated by use of recombinant technology. Briefly, an extracellular domain of dectin-2 cDNA was subcloned to an expression vector, which was then transfected to and expressed in E.cli. Soluble recombinant protein was recovered from lysates of coli, purified and its inhibitory activity to cognate dectin-2 was ascertained in in vitro assays. To address the initial questions, sDec2 was injected to mice before either the … More induction or the elicitation of CHS. However, CHS was not affected regardless of the injection, indicating that dectin-2-mediated pathways are not involved in this event By contrast, if dectin-2 was injected to mice which was already UV exposed at 1,000J/m^2 for 4 consecutive days. Those mice were then hapten sensitized and challenged, leading to full outcome of CHS, while UV significantly suppressed CHS when those were only sensitized and challenged but not sDec2-injected. This indicates that dectin-2 is involved in the UV-mediated impairment of CHS. To check for its involvement in UV-induced tolerance, mice whose CHS were impaired by UV were left untreated for 14 days and then resensitized and rechallenged, resulting that CHS was significantly suppressed as compared to unexposed animals, indicating that tolerance was induced. However, sDec2-injection before the first sensitization restored CHS and did not lead to tolerance. Based on the fact that tolerance is mediated via generation of T suppressor cells(Ts), the above mentioned results indicate that dectin-2 mediates the induction of hapten specific Ts. This was further confirmed as sDec2-bound, but not unbound T cells impaired the induction of CHS upon transfer to naive recipients. To phenotypically characterize sDec2-bound Ts, FACS analysis was conducted, demonstrating that UV-induced Ts express CD4 and CD25 on their surface resembling currently hightlighted regulatory T cells(Ir). Tr are the re-nomenclatured Ts, which possess the ability to prevent the onset of autoimmune disorders, including type I diabetes mellitus or multiple sclerosis of murine models. Together, our study disclosed that UV-induced tolerance is mediated via generation of Tr, Less

已知紫外线B光（UV）损害接触性超敏反应（CHS）的诱导期，随后诱导耐受。虽然这种现象几十年来一直被认为是一个重要的生物学意义，但这一事件背后的免疫学机制尚不完全清楚，Dectin-2是c型凝集素的新成员，它选择性地表达在表皮朗格汉斯细胞（LC）上。我们研究了dectin-2在UVB诱导的CHS免疫耐受中的作用。为此，我们首先生成了可溶性形式的dectin-2（sDec 2）。通过使用重组技术产生sDec 2。简言之，将dectin-2 cDNA的胞外结构域亚克隆到表达载体中，然后将其转染到大肠杆菌中并在其中表达。从大肠杆菌裂解液中回收可溶性重组蛋白，纯化并在体外测定中确定其对同源dectin-2的抑制活性。为了解决最初的问题，sDec 2被注射到小鼠体内， ...更多信息 诱导或诱发CHS。然而，无论注射与否，CHS都没有受到影响，表明dectin-2介导的途径不参与该事件。相反，如果将dectin-2注射到已经在1，000 J/m^2下连续4天UV暴露的小鼠中。然后将这些小鼠半抗原致敏和激发，导致CHS的完全结果，而当仅致敏和激发但不注射sDec 2时，UV显著抑制CHS。这表明dectin-2参与了UV介导的CHS损伤。为了检查其参与UV诱导的耐受性，将CHS被UV损伤的小鼠保持未处理14天，然后再致敏和再激发，结果与未暴露的动物相比，CHS被显著抑制，表明耐受性被诱导。然而，在第一次致敏之前注射sDec 2恢复了CHS，并且没有导致耐受性。基于耐受性是通过产生T抑制细胞（Ts）介导的事实，上述结果表明dectin-2介导半抗原特异性Ts的诱导。这被进一步证实为sDec 2结合的T细胞而不是未结合的T细胞在转移至初始受体后损害CHS的诱导。为了表型表征sDec 2结合的Ts，进行了FACS分析，证明UV诱导的Ts在其表面上表达CD 4和CD 25，类似于目前突出显示的调节性T细胞（Ir）。Tr是重新命名的Ts，其具有预防自身免疫性疾病（包括鼠模型的I型糖尿病或多发性硬化症）发作的能力。总之，我们的研究表明，紫外线诱导的耐受性是通过产生Tr，Less

项目成果

Maeda A, Matsushita K, Yamazaki F, Kawada A, Tezuka T, Aragane Y.: "Terfenadine antagonism against interleukin-4-modulated gene expression of T cell cytokines."J Invest Dermatol. 121. 490-495 (2003)

Maeda A、Matsushita K、Yamazaki F、Kawada A、Tezuka T、Aragane Y.：“特非那定对抗白细胞介素 4 调节的 T 细胞因子基因表达的拮抗作用。”J Invest Dermatol。

Schwarz A, Aragane Y, et al.: "Ultraviolet radiatibh-induced regulatory T cells hot only inhibit the induction but can suppress the effector phase of contact hypersensitivity"J Immunol. 172. 1036-1043 (2004)

Schwarz A、Aragane Y 等人：“紫外线辐射诱导的调节性 T 细胞热仅抑制诱导，但可以抑制接触性超敏反应的效应期”JImmunol。

Aragane Y, Maeda A, Schwarz T, Tezuka T, Ariizumi K, Schwarz T.: "Involvement of dectin-2 in ultraviolet radiation-induced tolerance."J Immunol. 171. 3801-3807 (2003)

Aragane Y、Maeda A、Schwarz T、Tezuka T、Ariizumi K、Schwarz T.：“dectin-2 参与紫外线辐射诱导的耐受性。”J 免疫学杂志。

Schwarz A, Maeda A, Wild MK, Kernebeck K, Gross N, Aragane Y, Beissert S, Vestweber D, Schwarz T.: "Ultraviolet radiation-induced regulatory T cells not only inhibit the induction but can suppress the effector phase of contact hypersensitivity."J Immunol.

Schwarz A、Maeda A、Wild MK、Kernebeck K、Gross N、Aragane Y、Beissert S、Vestweber D、Schwarz T.：“紫外线辐射诱导的调节性 T 细胞不仅抑制诱导，还可以抑制接触超敏反应的效应期

Yamazaki F, Aragane Y, et al.: "Overactivation of IL-4-induced activator protein-1 in atopic dermatitis"J Dermatol Sci. 28. 227-233 (2002)

Yamazaki F、Aragane Y 等人：“特应性皮炎中 IL-4 诱导的激活蛋白 1 的过度激活”J Dermatol Sci。