Department of Cellular and Molecular Immunology, Mie Graduate School of Medicine, Tsu, Mie, Japan.
Immunobiology. 2010;215(2):124-32. doi: 10.1016/j.imbio.2009.01.013. Epub 2009 May 17.
It is well documented that exposure to ultraviolet (UV) radiation in sunlight before immunization suppresses systemic as well as local immune responses. We have previously shown that administrating UV irradiation 7 days after immunization also suppresses Th1- and Th2-driven antibody (Ab) via generation of antigen (Ag)-specific CD4(+) regulatory T cells. In this study, we specifically show that IL-10, which is produced by CD4(+) regulatory T cells generated in mice that received UV irradiation after immunization, mediates the suppression of Ab responses by inhibiting Th cell activation. In addition, IL-10 produced upon Ag-specific activation by UV-induced regulatory T cells also mediates bystander suppression. Furthermore, because UV irradiation after immunization effectively dampens both Th1 and Th2 immune responses, we further demonstrated that mice receiving UV irradiation after allergen sensitization had reduced Th2-driven airway inflammation and airway hyperreactivity (AHR). These results suggest that UV irradiation in pre-sensitized individuals induces Ag-specific IL-10 producing regulatory T cells representing type 1 regulatory T cells that suppress Th2 immunity and may have therapeutic potential for asthmatic patients.
有充分的文献记载表明，在免疫接种前暴露于阳光中的紫外线（UV）辐射会抑制全身和局部免疫反应。我们之前已经表明，在免疫接种后 7 天给予 UV 照射也会通过产生抗原（Ag）特异性 CD4+调节性 T 细胞来抑制 Th1 和 Th2 驱动的抗体（Ab）。在这项研究中，我们特别表明，在接受免疫接种后接受 UV 照射的小鼠中产生的 IL-10 由 CD4+调节性 T 细胞产生，通过抑制 Th 细胞激活来介导 Ab 反应的抑制。此外，由 UV 诱导的调节性 T 细胞通过 Ag 特异性激活产生的 IL-10 也介导旁观者抑制。此外，由于免疫接种后接受 UV 照射可有效抑制 Th1 和 Th2 免疫反应，我们进一步证明，在过敏原致敏后接受 UV 照射的小鼠具有减少的 Th2 驱动的气道炎症和气道高反应性（AHR）。这些结果表明，在致敏个体中进行 UV 照射会诱导 Ag 特异性产生 IL-10 的调节性 T 细胞，代表 1 型调节性 T 细胞，可抑制 Th2 免疫，并且可能对哮喘患者具有治疗潜力。
