【摘要】：[背景]白假絲酵母菌(Candida albicans, C.albicans,白色念珠菌)是臨床上最常見(jiàn)的致病性真菌,可引起各種念珠菌病。深入研究抗C.albicans感染免疫,意義重大。C.albicans可因環(huán)境條件改變由一種形態(tài)轉(zhuǎn)變?yōu)榱硪环N形態(tài),為二態(tài)性真菌。C.albicans由酵母相(Yeast form, Y)向菌絲相(Hyphal form, H)轉(zhuǎn)化是其感染性轉(zhuǎn)變的關(guān)鍵因素。 甘露聚糖結(jié)合凝集素(mannan-binding lectin, MBL)是由肝細(xì)胞分泌的血漿蛋白,被稱(chēng)為“天然免疫系統(tǒng)中的關(guān)鍵分子”,目前,已經(jīng)報(bào)道的有關(guān)MBL抗C.albicans作用主要是通過(guò)激活補(bǔ)體發(fā)揮調(diào)理吞噬作用。但是,作為天然免疫關(guān)鍵分子,MBL除了通過(guò)激活補(bǔ)體促進(jìn)對(duì)C.albicans的調(diào)理吞噬外,是否還有其他作用?是否可通過(guò)調(diào)節(jié)C.albicans相態(tài)轉(zhuǎn)化和其誘導(dǎo)免疫反應(yīng),從而發(fā)揮抗C.albicans感染的作用?至今無(wú)相關(guān)報(bào)道,但潛在研究意義重大。 [目的]1.分析不同濃度MBL對(duì)C.albicans二相性轉(zhuǎn)化的影響；2.揭示MBL調(diào)節(jié)C.albicans相態(tài)轉(zhuǎn)化的機(jī)制；3.初步探討MBL對(duì)C.albicans刺激外周血單個(gè)核細(xì)胞(Peripheral blood mononuclear cell, PBMC)產(chǎn)生免疫反應(yīng)的調(diào)節(jié)作用。 [方法]1.用親和層析法,分離純化人血漿MBL;2.倒置顯微鏡觀(guān)察不同濃度的MBL對(duì)C.albicans相態(tài)轉(zhuǎn)化的影響；3.用RealTime RT-PCR分析MBL對(duì)C.albicans相態(tài)轉(zhuǎn)化過(guò)程中關(guān)鍵調(diào)控基因表達(dá)情況；4.Ficoll密度梯度離心法分離PBMC;5.ELSIA檢測(cè)MBL對(duì)C.albicans刺激PBMC產(chǎn)生細(xì)胞因子的影響。 [結(jié)果]1.MBL能夠抑制C.albicans由酵母相向菌絲相轉(zhuǎn)化;2.MBL能夠抑制C.albicans相態(tài)轉(zhuǎn)化過(guò)程中關(guān)鍵調(diào)控基因HWP1的表達(dá)；3.低濃度MBL(生理濃度)對(duì)C.albicans刺激PBMC分泌IFN-γ、TNF-α及IL-6具有促進(jìn)作用,高濃度MBL(超生理濃度)則對(duì)上述細(xì)胞因子的分泌有抑制作用。 [結(jié)論]1.MBL能夠通過(guò)調(diào)節(jié)HWP1基因的表達(dá)抑制C.albicans由酵母相向菌絲相轉(zhuǎn)化；2.MBL能夠以濃度依賴(lài)方式雙向調(diào)節(jié)C.albicans誘導(dǎo)的細(xì)胞因子分泌。提示MBL作為天然免疫的關(guān)鍵分子在C.albicans相態(tài)轉(zhuǎn)化及其誘導(dǎo)的免疫反應(yīng)中均具有作用。
[Abstract]:[background] Candida albicans (Candida albicans, C.albicans) is the most common pathogenic fungus in clinic, which can cause various Candida albicans. It is of great significance to study the immunity against C.albicans infection. C.albicans can be changed from one form to another form because of the change of environmental conditions. C.albicans can be transformed from yeast to hyphae from (Yeast form, Y) to (Hyphal form,. H) transformation is the key factor of its infectious transformation. Mannan-binding lectin (mannan-binding lectin, MBL), a plasma protein secreted by hepatocytes, is known as a "key molecule in the innate immune system". It has been reported that the anti-C.albicans effect of MBL is mainly by activating complement to regulate phagocytosis. However, as a key molecule of innate immunity, does MBL have other functions besides activating complement to promote the regulation and phagocytosis of C.albicans? Can the effect of C.albicans infection be played by regulating the phase transformation of C.albicans and its induction of immune response? No relevant reports have been reported so far, but the potential research is of great significance. [objective] 1. The effects of different concentrations of MBL on the two-phase transformation of C.albicans were analyzed. 2. The mechanism of MBL regulating C.albicans phase transition was revealed. 3. To investigate the effect of MBL on the immune response of peripheral blood mononuclear cells (Peripheral blood mononuclear cell, PBMC) stimulated by C.albicans. [methods] 1. Purification of human plasma MBL;2. by affinity chromatography The effects of different concentrations of MBL on the phase transition of C.albicans were observed by inverted microscope. RealTime RT-PCR was used to analyze the expression of key regulatory genes in the phase transformation of C.albicans by MBL and PBMC;5.ELSIA was separated by 4.Ficoll density gradient centrifugation to detect the effect of MBL on the cytokines produced by C.albicans stimulated PBMC. [results] 1.MBL could inhibit the transformation of C.albicans from yeast to hyphae, 2.MBL could inhibit the expression of key regulatory gene HWP1 in the process of C.albicans phase transformation. Low concentration of MBL (physiological concentration) promoted the secretion of IFN- 緯, TNF- 偽 and IL-6 by PBMC stimulated by C.albicans, and high concentration of MBL (superphysiological concentration) inhibited the secretion of these cytokines. [conclusion] 1.MBL can inhibit the transformation of C.albicans from yeast to hyphae by regulating the expression of HWP1 gene, and 2.MBL can regulate cytokine secretion induced by C.albicans in a concentration-dependent manner. It is suggested that MBL, as a key molecule of innate immunity, plays an important role in the phase transformation of C.albicans and its induced immune response.
【學(xué)位授予單位】：新鄉(xiāng)醫(yī)學(xué)院
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2013
【分類(lèi)號(hào)】：R379.4

【參考文獻(xiàn)】

中國(guó)期刊全文數(shù)據(jù)庫(kù) 前2條

1 郭明衛(wèi);彭文娟;;常見(jiàn)深部真菌感染性疾病的研究進(jìn)展[J];河北醫(yī)藥;2009年01期

2 蘇惠春;程波;;白念珠菌雙形態(tài)性的分子調(diào)節(jié)機(jī)制[J];中國(guó)真菌學(xué)雜志;2006年04期

，

本文編號(hào)：2305353