- 學位論文
探討ketotifen對骨髓樹突細胞 的免疫調節作用
Study on the modulatory effect of ketotifen on murine bone marrow- derived dendritic cell
摘要
前言：Ketotifen是一種組織胺H1接受器的反向激動劑，應用於預防氣喘與過敏疾病。樹突細胞表面會表現四種組織胺接受器H1~H4，且會受到組織胺的影響。但是，ketotifen對樹突細胞的影響並不清楚。 實驗方法：利用GM-CSF加上IL-4或是只有GM-CSF培養骨髓樹突細胞，再以ketotifen處理骨髓樹突細胞後，分析上清液中細胞激素的表現量，且觀察ketotifen對骨髓樹突細胞的成熟度以及刺激T細胞增生的影響。 結果：我們的結果顯示，隨著ketotifen濃度的增加，抑制了骨髓樹突細胞分泌發炎性細胞激素TNF-?悀呰L-6。在LPS存在的情況下，ketotifen可抑制骨髓樹突細胞表現IL-12及IL-6；而在poly IC刺激下，ketotifen可降低IL-6的表現量。在成熟度方面，ketotifen並不會改變骨髓樹突細胞表面分子如：MHC class II，CD86，CD40的表現情形。此外，ketotifen處理過的骨髓樹突細胞會促進T細胞的增生。 結論：我們證實了無論有無LPS或Poly IC的刺激，ketotifen皆可抑制樹突細胞分泌與發炎相關的細胞激素，我們的研究幫助了解ketotifen在過敏性疾病之治療機制。
並列摘要
Background: Histamine has been demonstrated to affect allergic inflammatory responses. Dendritic cells can synthesize histamine and express all four histamine H1 to H4 receptors. Ketotifen is a H1-receptor inverse agonist and used for the management of asthma and allergic disorders. We examined the effect of ketotifen on murine bone marrow-derived DCs (BM-DCs) in vitro. Methods: Murine BM-DCs were pre-treated with ketotifen following 24-hour lipopolysaccharide (LPS) stimulation. The phenotypic analysis of treated BM-DCs was examined by flow cytometry, cytokine secretion was assayed by multiplex immunoassay and T-cell proliferative response was determined by mixed lymphocyte reaction. Results: We observed that ketotifen significantly inhibited BM-DCs to secrete TNF-?? and IL-6 in dose-dependent manner without stimulus (LPS or poly IC). Moreover, ketotifen significantly inhibited IL-12 and IL-6 production from LPS-stimulated BM-DCs and IL-6 secretion from poly IC-treated BM-DCs. In addition, ketotifen induced the ability of BM-DCs to stimulate CD4+ T-cell proliferation in mixed lymphocyte reaction. Conclusions: We demonstrated that ketotifen can inhibit the pro-inflammatory cytokine secretion from BM-DCs with or without TLR4 and TLR3 stimulation in vitro. Our study facilitates the understanding of therapeutic mechanism of ketotifen in allergic inflammation.