本文選題：殼聚糖衍生物 + 不同構(gòu)型　； 參考：《中國(guó)科學(xué)院研究生院(海洋研究所)》2015年碩士論文

【摘要】：新城疫是由新城疫病毒(NDV)引起的禽類(lèi)的一種以呼吸道、消化道黏膜出血為典型癥狀的高度接觸性、急性敗血性傳染病。目前防治雞新城疫的手段主要以預(yù)防為主,多采用疫苗方法。近年來(lái)大量研究表明,海洋生物多糖具有抗病毒和提高機(jī)體免疫力的活性。殼聚糖作為天然存在的唯一帶正電荷的多糖,具有調(diào)節(jié)免疫、抗腫瘤、抗菌、降脂、保濕等非常好的生物活性。且研究發(fā)現(xiàn),殼聚糖及其衍生物可抑制幾十種植物病毒、類(lèi)病毒的侵染,但其是否具有抗新城疫病毒活性,國(guó)內(nèi)外還未見(jiàn)報(bào)道。本文首次以不同分子量、不同結(jié)構(gòu)類(lèi)型、不同基團(tuán)修飾的α-殼聚糖、β-殼聚糖和6-胺取代-6-脫氧殼聚糖衍生物為原料,以雞胚尿囊液中血凝效價(jià)的降低作為指標(biāo),針對(duì)不同樣品抗雞新城疫病毒活性進(jìn)行了篩選;同時(shí),采用熒光定量PCR技術(shù),測(cè)定免疫因子基因表達(dá)的變化,研究殼聚糖衍生物對(duì)于免疫系統(tǒng)的激活與調(diào)控作用,從而確定殼聚糖衍生物對(duì)于機(jī)體免疫系統(tǒng)的影響及藥效作用機(jī)制。具體結(jié)果如下:測(cè)試樣品均具有抗新城疫病毒活性,分子量、分子結(jié)構(gòu)、修飾基團(tuán)、樣品濃度和接種時(shí)間的差異對(duì)活性影響顯著。1)α-殼聚糖和β-殼聚糖的抗新城疫病毒活性因分子量和濃度的不同而不同,最佳分子量分別為4513 Da和5743 Da,具有劑量依賴(lài)關(guān)系;2)β-殼聚糖的抗新城疫病毒活性明顯優(yōu)于α-殼聚糖,β-殼聚糖在分子量為3 kDa-6 kDa時(shí),效果非常顯著,可有效降低病毒血凝效價(jià)至0;3)6-脫氧-N-鄰苯二甲�；鶜ぞ厶呛�6-脫氧-6-溴代-N-鄰苯二甲�；鶜ぞ厶悄軌蝻@著抑制新城疫病毒,可有效降低血凝效價(jià)至0,且效果好于低分子量α-殼聚糖及β-殼聚糖。熒光定量PCR測(cè)定結(jié)果表明:低分子量α-殼聚糖、β-殼聚糖能有效增強(qiáng)IL-2、IFN-α、IFN-β、TNF-α等免疫因子的基因表達(dá),病毒RNA基因表達(dá)無(wú)明顯變化。而經(jīng)胺取代修飾的殼聚糖衍生物具有顯著的抗新城疫病毒活性,同時(shí)有效調(diào)節(jié)免疫因子的基因表達(dá),減少病毒RNA基因表達(dá)。本研究為獲得一種綠色低毒、治療有效的抗新城疫病毒類(lèi)藥物提供了可能。同時(shí),也為我們系統(tǒng)性研究治療其它免疫損傷性疾病奠定了基礎(chǔ)。
[Abstract]:Newcastle disease (NDV) is a highly contact and acute septic infectious disease caused by Newcastle disease virus (NDV) in poultry with respiratory tract and gastrointestinal bleeding as typical symptoms. At present, the prevention and treatment of Newcastle disease are mainly based on prevention and vaccine. In recent years, a large number of studies have shown that marine polysaccharides have antiviral and immune activities. Chitosan, as the only positively charged polysaccharide, has very good biological activities such as immune regulation, anti-tumor, antibacterial, lipid-lowering, moisturizing and so on. It was found that chitosan and its derivatives could inhibit the infection of dozens of plant viruses and viroids, but whether they had the activity of resisting Newcastle disease virus had not been reported at home and abroad. In this paper, 偽 -chitosan, 尾 -chitosan and 6-amine substituted -6-deoxychitosan derivatives modified with different molecular weight, different structural types and different groups were used as raw materials for the first time. The reduction of hemagglutination titer in chicken embryo allantoic fluid was used as an index. The activity of different samples against Newcastle disease virus (NDV) was screened, and the changes of gene expression of immune factors were determined by fluorescence quantitative PCR, and the activation and regulation of chitosan derivatives on immune system were studied. The effects of chitosan derivatives on the immune system and the mechanism of pharmacodynamics were determined. The results are as follows: the tested samples have anti-Newcastle disease virus activity, molecular weight, molecular structure, modified group, The difference of sample concentration and inoculation time had a significant effect on the activity of 偽 -chitosan and 尾 -chitosan. The activity of anti-Newcastle disease virus was different with the molecular weight and concentration of 偽 -chitosan and 尾 -chitosan. The optimum molecular weight was 4513 Da and 5743 Da, respectively. The anti-Newcastle disease virus activity of 尾 -chitosan in a dose-dependent manner was significantly better than that of 偽 -chitosan. When the molecular weight of 尾 -chitosan was 3 kDa-6 kDa, the effect of 尾 -chitosan was very significant. The hemagglutination titer of the virus was reduced to 0 ~ (3) ~ (3) -deoxy-N-phthalyl chitosan and 6-deoxy-6-bromo-N-phthalyl chitosan, which could significantly inhibit Newcastle disease virus. The hemagglutination titer was reduced to 0, and the effect was better than that of low molecular weight 偽 -chitosan and 尾 -chitosan. The results of fluorescence quantitative PCR showed that low molecular weight 偽 -chitosan and 尾 -chitosan could effectively enhance the expression of IFN- 偽, IFN- 尾, TNF- 偽 and other immune factors, but the expression of virus RNA gene had no significant change. The chitosan derivatives modified by amines have significant anti-Newcastle disease virus activity and can effectively regulate the gene expression of immune factors and reduce the RNA gene expression of the virus. In this study, it is possible to obtain a green low-toxicity and effective anti-Newcastle disease virus drugs. At the same time, it also lays the foundation for systematic research on other immune damage diseases.
【學(xué)位授予單位】：中國(guó)科學(xué)院研究生院(海洋研究所)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類(lèi)號(hào)】：R943;R96

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 高煥;韓立秋;胡林;張亞寧;王德云;;硫酸化人參皂苷體外抗新城疫病毒作用[J];中草藥;2011年12期

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本文編號(hào)：1987369