畜牧兽医学报  2022, Vol. 53 Issue (7): 2066-2073. DOI: 10.11843/j.issn.0366-6964.2022.07.004    PDF    
中药多糖作为免疫增强剂及其对肠道黏膜影响的研究进展
伯若楠1,2, 王晶1, 刘晓盼1, 刘明江1,2, 李金贵1,2     
1. 扬州大学兽医学院, 扬州 225009;
2. 江苏省高校动物重要疫病与人兽共患病 防控协同创新中心, 扬州 225009
摘要:黏膜是机体免疫的第一道防线,口服、滴鼻、点眼等黏膜免疫途径可有效诱导保护性黏膜免疫反应。但目前绝大多数的黏膜免疫疫苗仍未开发,且缺乏安全有效的免疫增强剂。中药多糖已被证实是一类具有促进黏膜免疫效应的生物活性大分子。本文对近年来不同类型的中药多糖作为免疫增强剂及其对肠道黏膜的影响进行综述,旨在为中药多糖作为黏膜免疫增强剂的开发利用提供新思路。
关键词中药多糖    肠道黏膜免疫    免疫增强剂    
Research Progress of Chinese Herbal Polysaccharides as Immunopotentiator and Its Effect on Intestinal Mucosa
BO Ruonan1,2, WANG Jing1, LIU Xiaopan1, LIU Mingjiang1,2, LI Jingui1,2     
1. College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China;
2. Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
Abstract: Mucosa is the frontline of body immune defense. Protective mucosal immune response can be effectively induced by oral administration, nose drop, ocular routes and other mucosal routes. However, most mucosal immune vaccines have not been developed, and there is a lack of safe and effective immunopotentiator. Chinese herbal polysaccharides have been proved as biologically-active macromolecules to promote mucosal immune response. This paper reviews different mucosal immunopotentiator of Chinese herbal polysaccharides and its effect on intestinal mucosa in recent years, in order to provide new ideas for the development and utilization of Chinese herbal polysaccharides as mucosal immune immunopotentiator.
Key words: Chinese herbal polysaccharides    intestinal mucosal immunity    immunopotentiator    

随着我国畜禽养殖业的快速发展,规模化、集约化养殖程度的不断提高,动物疫病暴发的风险也越来越大。大多数病原微生物主要是通过黏膜途径入侵动物机体的,如大肠杆菌、沙门菌、猪流行性腹泻病毒、轮状病毒等[1-3]。肠道是动物体腔与外界环境的最大接触面,易被肠道病原体定植和入侵,而肠道黏膜就构成了保护动物机体免受外来病原微生物侵扰的第一道重要防线。通过黏膜途径接种疫苗能更容易、更有效地诱导保护性黏膜免疫反应,切断病原体的感染途径[4]。研究与实践证明消化道黏膜免疫不仅在局部和其他黏膜组织产生免疫应答,还可激发全身性体液免疫应答[5]。然而,传统的活疫苗和弱毒活疫苗,虽然可以增强体液和细胞免疫反应,但安全性较差。亚单位抗原、重组蛋白的新型疫苗和灭活疫苗虽然更加安全,但免疫原性较差,且目前使用的大多数疫苗都是肌肉或皮下注射接种,无法直接作用于黏膜来激发黏膜免疫反应[6]。一种成功的黏膜疫苗需要同时激活先天免疫系统和适应性免疫系统,以实现最佳的保护作用和持续时间[7],但目前所应用的抗原通常会受到肠消化液的降解,诱导的反应相对较弱。因此,为诱导有效的黏膜免疫应答,适当的免疫增强剂是必要的[8]

针对肠道复杂的环境,人们一直努力探索潜在的新型黏膜免疫增强剂[9-10]。多糖是生物体中广泛存在的物质。现今植物多糖研究日益受到关注,国际科学界甚至提出21世纪是多糖的世纪。许多研究表明,中药多糖安全低毒,具有抗炎、抗癌、免疫调节等多种生物活性,是一种优良的免疫增强剂[11]。中药多糖通过激活树突状细胞并促进其成熟、激活巨噬细胞功能、促进T/B淋巴细胞的增殖和活化、抑制Tregs的功能,增加转录因子NOD样受体蛋白3(NLRP3)的表达等多种作用机制发挥免疫增强效应[12]。但中药多糖通常作为系统免疫增强剂使用[13-16],应用于黏膜免疫的相对较少,且它们的黏膜免疫效力尚未得到系统性评价。因此,本文对近年来应用于黏膜免疫的不同类型的中药多糖免疫增强剂,以及中药多糖对肠道黏膜的影响进行了综述,以期为开发安全有效的新型黏膜免疫增强剂提供更多新思路。

1 不同类型的中药多糖黏膜免疫增强剂

研究表明,多种中药多糖具有增强黏膜免疫的作用,如地黄多糖[17]、黄芪多糖[18]、香菇多糖[19]、黑灵芝多糖[20]、淫羊藿多糖[21]等,可以作为黏膜免疫增强剂的候选药物。然而,受自身结构或理化性质的影响,中药多糖存在临床用量大、靶向性差的问题。为了进一步提高中药多糖的生物活性或者改变药物剂型,研究者们对中药多糖进行了不同类型的修饰与利用,如化学修饰、物理装载和微生物发酵等,制备出比天然中药多糖效果更佳的免疫增强剂,以期提高中药多糖的生物利用度和靶向性。

1.1 化学方法修饰中药多糖

对多糖进行化学修饰是开发多糖类药物的重要途径之一。对于多糖的化学修饰,最常见的方法是硒化、硫酸化、磷酸化、羧甲基化、乙酰化等[22]。通过化学方式来改变或重建多糖结构,可得到具有更全面生物活性的多糖衍生物,从而产生不一样的生理活性,进一步拓宽其临床应用范围[23]。其中硒化多糖较为常见,硒多糖是多糖和硒相结合的产物,不仅兼有硒和多糖各自的生物活性,还具有硒多糖所特有的生物活性[24]。之前的研究证明,硒化修饰大蒜多糖(sGPS)是一种安全有效的潜在黏膜免疫增强剂,与疫苗免疫对照组相比,sGPS可显著提高鸡新城疫血凝抑制(HI)的抗体滴度,促进空肠和气管冲洗液分泌型IgA(sIgA)、IFN-γ、IL-2的分泌[25]。金清[26]将黄芪多糖协同硫酸化淫羊藿多糖灌喂仔猪后发现,明显改善了仔猪小肠肠道的形态,提高了仔猪十二指肠、空肠、回肠sIgA的含量,激活了肠道TLR4/NF-κB介导的IRF-3依赖信号通路来调节宿主免疫功能。两种多糖的协同作用显著改善仔猪肠道的组织结构发育和物理屏障功能。研究表明多糖衍生物可作为黏膜免疫增强剂被更为广泛的应用。

1.2 利用递送载体装载中药多糖

将中药多糖直接用于黏膜免疫增强剂不能突破黏膜系统复杂结构的限制以及免受酸性环境的破坏,而药物递送载体可有效改善这一情况[27]。脂质体、PLGA、壳聚糖等药物递送载体装载多糖后,不仅可以抵抗外界物质的破坏,还能对载体表面进行适当修饰,增加其靶向性。因此,中药多糖通过药物递送载体的装载,可以提高多糖口服的生物利用度,诱导机体获得更佳的免疫应答效应。

脂质体可以被抗原递呈细胞(APC)内吞,可有效地作为黏膜疫苗传递系统发挥作用。Kaneko等[28]发现将药物包入脂质体后口服给药,药物可靶向并被摄入到派伊尔小结(Peyer结)中,诱导黏膜免疫反应。周兆海等[29]研究发现,玉屏风多糖脂质体能够促进雏鸡接种禽流感疫苗的免疫效果,增强机体肠黏膜免疫功能,作用效果优于玉屏风多糖。玉屏风多糖脂质体显著增加小肠绒毛长度、小肠上皮内和固有层淋巴细胞数量,并促进盲肠扁桃体淋巴细胞的成熟和增殖,高剂量玉屏风多糖脂质体比天然玉屏风多糖的效果更佳[30]。另外,壳聚糖纳米粒子具有低毒性、良好的生物降解性和黏附性等特性,作为口服疫苗载体可以保持缓慢和持续的抗原释放,有效防止抗原在到达黏膜组织诱导部位之前被降解,激活全身黏膜和系统免疫应答[31-34]。此外,PLGA[35]、微胶囊等药物递送载体也具有一定的开发潜力被用于中药多糖装载。

1.3 其他类型的中药多糖黏膜免疫增强剂

1.3.1 微生物发酵中药多糖   发酵是中药炮制的重要方法之一,是利用微生物发酵中草药来提高其有效成分的提取率和药效。这样能最大限度地保护中药活性物质免遭破坏,还能将许多大分子活性物质降解为可直接吸收利用的小分子活性物质。另外,微生物可分解中药内有毒成分,降低中药的毒副作用[36]。梁子敬[37]使用鸡盲肠内容物分离得到的非解乳糖链球菌FGM发酵处理黄芪(FAPS),发现多糖的提取率显著提高,且多糖结构无明显改变。连续灌胃后,FAPS有效缓解了环磷酰胺(CY)造成的肠道黏膜损伤以及肠道上皮细胞黏附连接损伤。因此,发酵多糖可以被开发作为黏膜免疫增强剂。

1.3.2 离子辐射修饰中药多糖   离子辐射是通过射线断裂天然多糖中糖苷键的一种物理修饰方法。与其他改性方法(如酸水解和酶处理)相比,使用离子辐射拥有更高的重复性和产率,对环境友好。与黄芪多糖(APS)相比,γ-辐射黄芪多糖(IAPS)分子量和黏度降低,溶解度增加,更容易通过肠道M细胞穿透屏障,刺激黏膜免疫反应[38]。口服IAPS后,免疫抑制鸡的空肠杯状细胞计数和十二指肠上皮内淋巴细胞、IgA+浆细胞计数比黄芪多糖组相关指标更高。因而,离子辐射修饰中药多糖可以作为一种潜在的替代方法被用于开发新型黏膜免疫增强剂。

2 中药多糖作为免疫增强剂对肠道黏膜的影响

不同类型的中药多糖被开发作为免疫增强剂,有研究表明中药多糖具有修复肠道黏膜损伤和促进肠道黏膜免疫的作用。而且它们在肠道黏膜中发挥作用的方式是多样的,主要通过以下几种方式:影响肠道黏膜机械屏障和免疫细胞、影响肠道sIgA和细胞因子的分泌、影响肠道共生菌群等。

2.1 对肠道黏膜机械屏障的影响

肠道机械屏障由肠上皮细胞和细胞间的紧密连接蛋白组成,是保护肠道免受外部环境中病原体或有害物质侵入肠黏膜的关键,也是维持肠上皮选择性通透性及其屏障功能的结构基础[39]。紧密连接蛋白是由跨膜蛋白occludin、claudin-1及胞内蛋白ZO-1组成[40],而肠道上皮细胞(IEC)主要有柱状上皮细胞、M细胞、杯状细胞、潘氏细胞、内分泌细胞和未分化细胞等,其细胞具有快速增殖和再生能力,以维持肠黏膜机械屏障功能[41]。M细胞在黏膜免疫应答中起重要的作用,缺乏M细胞的小鼠,其浆细胞发育迟缓[42]。靶向M细胞的抗原递送是增强黏膜免疫应答的上佳策略[43-45]。口服香菇多糖后,免疫抑制小鼠的Peyer结中的M细胞数量部分恢复[46],并且由于进入胃肠道的中药多糖具有高亲水性和大尺寸的特点,无法被机体直接消化吸收,也难以被肠上皮细胞转运,但它可以被肠内Peyer结吸收,靶向于M细胞转运,从而影响肠黏膜免疫系统。此外,Xie等[47]的研究结果表明,霍山石斛多糖可上调紧密连接蛋白的表达,改善肠道物理屏障功能。灵芝菌丝多糖通过上调occludin的表达、降低肠道通透性来改善大鼠肠道机械屏障功能[48]。杯状细胞的缺失会导致黏液层缺陷,最终使细菌与表面上皮的黏附增加,增加病原微生物入侵的风险。黑灵芝多糖通过增加杯状细胞数量和上调紧密连接蛋白表达量,可恢复小鼠因CY导致受损的黏膜屏障[49]

2.2 对肠道sIgA、细胞因子分泌的影响

中药多糖除了有助于保护肠道机械屏障的完整性之外,对肠道黏膜抗体和细胞因子分泌也有促进作用。sIgA是黏膜免疫的主效因子,占黏膜相关组织产生的所有抗体的80%以上[50],是黏膜免疫反应的标志。sIgA能与相应病原微生物结合,阻止病原体黏附到细胞表面,而使其丧失感染能力,在保护黏膜屏障方面发挥着重要作用[51]。此外,sIgA主要是由黏膜固有层IgA+浆细胞合成分泌,IgA+浆细胞的形成是产生大量sIgA的关键[52]。而固有层浆细胞分泌的二聚体IgA需与上皮膜上的多聚免疫球蛋白受体(pIgR)结合才可刺激细胞转运,每个sIgA的转运都需消耗一个pIgR分子,pIgR的大量产生也是sIgA跨细胞发挥作用的关键[53-55]。口服黄芪多糖能增加空肠中IgA+细胞的数量,导致分泌更多的sIgA,有利于增强肠黏膜免疫功能[56]。此外,黄芪多糖也显著升高了鸡空肠中NDV特异性sIgA水平,显著增强了鸡黏膜对NDV疫苗的免疫应答。龙眼肉多糖通过改善IgA浆细胞的生成和迁移、增加pIgR的表达,从而加强sIgA的肠道分泌[57]

受抗原刺激后,肠道黏膜免疫细胞可产生大量细胞因子。细胞因子间相互促进或拮抗,共同参与肠道黏膜免疫调节。目前研究较多的是炎性细胞因子(IL-2、IFN-γ、TNF-α)和抗炎性因子(IL-4、IL-5、IL-10)等[58]。IL-4是一种Th2细胞因子,可促进T淋巴细胞、B淋巴细胞和肥大细胞的增殖和分化,并在sIgA的形成中起重要作用。丘富安等[59]研究表明,参芪多糖口服液可增加CY免疫抑制鸡空肠黏膜中IL-4的浓度。此外,IFN-γ、TNF-α、IL-1及IL-4存在协同作用上调pIgR的表达,IL-17也被证明可增强黏膜上皮细胞中pIgR的表达,而pIgR的高效表达可促进sIgA的分泌。

2.3 对肠道黏膜免疫细胞的影响

研究表明,肠黏膜分布着大量的免疫细胞群,如巨噬细胞、树突状细胞和淋巴细胞等,在协调特异性黏膜免疫反应中起着关键作用[60]。为维持肠道黏膜完整性,肠道黏膜免疫细胞须对外源性和内源性潜在病原体作出适当且有效的免疫反应。肠黏膜中大量的淋巴细胞主要集中于三个重要区域,上皮层、黏膜固有层和黏膜淋巴样滤泡[61]。上皮内淋巴细胞的数量是评估小肠局部黏膜免疫屏障结构和功能完整性的良好指标[62],太子参茎叶多糖在一定程度提高了肠道黏膜上皮内淋巴细胞数量[63]。松花粉多糖有效缓解环磷酰胺导致的肠道Peyer结中CD3+T以及CD3+CD8+T比例的升高,同时可以使CD4+/CD8+T细胞比例恢复到正常水平[64]。研究表明松花粉多糖还通过TLR4/MAPK/NF-κB信号通路激活鸡巨噬细胞HD11细胞产生免疫应答[65]

此外,树突状细胞活化后,可促进效应T细胞分化,并诱导活化T细胞的迁移和B细胞的免疫反应[66-68]。鹿秀云等[69]证明,黄芪多糖通过调节结肠炎小鼠树突状细胞表面共刺激分子表达水平,影响肠道健康。另外,黄芪多糖还可通过诱导Peyer结中Tregs分化成熟和抑制IL-17分泌来对结肠炎起到保护作用[70]。经黄芪多糖治疗后,增加了结肠组织中CD4+CD25+T细胞和CD4+ CD25+ Foxp3+ T细胞的数量,并降低了IL-17的水平。

2.4 对肠道共生菌群的影响

肠道内存在着大量共生菌群,肠道菌群具有影响肠黏膜免疫系统的正常发育与成熟和调控肠黏膜屏障与免疫功能的双重作用[71]。Chen等[72]发现,黄连多糖可动态调节肠道菌群的多样性、组成和分布。Ying等[73]也证明,冬虫夏草多糖改善了微生物群落多样性,增加了益生菌(乳酸杆菌、双歧杆菌、类杆菌)的丰度,减少了病原菌(梭状芽胞杆菌、弯曲螺旋体)。术苦芩总多糖可抑制常见肠道致病菌生长,改变腹泻仔猪肠道微生物群的丰富度和多样性,提高乳酸杆菌属的相对丰度,并改善菌群结构(芽胞杆菌纲、乳酸杆菌属相对丰度显著上升,梭菌纲相对丰度极显著下降)[74]。此外,部分中药多糖还可通过抗氧化作用对肠道微环境产生影响。川芎多糖显著促进主要抗氧化酶(超氧化物歧化酶1、超氧化物歧化酶2、过氧化氢酶、谷胱甘肽硫转移酶1、谷胱甘肽硫转移酶M1)的表达,空肠和盲肠的抗氧化能力也显著增加,可有效对肠道的氧化应激产生保护作用[75]。上述研究表明,部分中药多糖可直接或间接诱导肠道菌群的变化,影响宿主肠道菌群的丰度、种类和比例。

3 小结与展望

目前,现代养殖业向集约化、规模化方向发展,以往的免疫接种方式如肌肉注射、皮下注射,不仅耗时费力、造成动物应激,且无法激发黏膜免疫应答,不能满足未来大规模养殖的发展趋势。因此,气雾、滴鼻、点眼、饮水等简单易行的黏膜免疫途径越来越受到关注,而开发安全有效的黏膜免疫增强剂就成为黏膜免疫的研究重点之一。中药多糖因其天然、低毒、无残留等优点成为研究热点。由化学修饰、物理装载和微生物发酵等方式获得的不同类型的中药多糖也各具优势。有研究表明中药多糖具有修复肠道黏膜损伤和促进肠道黏膜免疫的作用。然而,中药多糖的提取方式繁琐,中药材品种、来源、年份不同,导致提取率较低、不稳定,提取过程也对原材料造成大量浪费,无法大规模推广应用于临床。此外,关于中药多糖作为免疫增强剂的应用主要集中于全身系统免疫,对局部黏膜免疫影响的研究甚少,对肠道黏膜免疫机理的研究更少,这限制了中药多糖在黏膜免疫增强剂方面的应用。随着对中药多糖相关领域科学技术的日趋完善和提高,相信中药多糖的开发和利用在畜牧业将具有更加广阔的发展空间和应用前景。

参考文献
[1]
RICHARDS A F, TORRES-VELEZ F J, MANTIS N J. Salmonella uptake into gut-associated lymphoid tissues: implications for targeted mucosal vaccine design and delivery[J]. Methods Mol Biol, 2022, 2410: 305-324.
[2]
PEREZ-LOPEZ A, BEHNSEN J, NUCCIO S P, et al. Mucosal immunity to pathogenic intestinal bacteria[J]. Nat Rev Immunol, 2016, 16(3): 135-148. DOI:10.1038/nri.2015.17
[3]
CARVALHO M F, GILL D. Rotavirus vaccine efficacy: current status and areas for improvement[J]. Hum Vaccin Immunother, 2019, 15(6): 1237-1250. DOI:10.1080/21645515.2018.1520583
[4]
LI M, WANG Y, SUN Y, et al. Mucosal vaccines: strategies and challenges[J]. Immunol Lett, 2020, 217: 116-125. DOI:10.1016/j.imlet.2019.10.013
[5]
CRISCUOLO E, CAPUTO V, DIOTTI R A, et al. Alternative methods of vaccine delivery: an overview of edible and intradermal vaccines[J]. J Immunol Res, 2019, 2019: 8303648.
[6]
SHAKYA A K, CHOWDHURY M Y E, TAO W Q, et al. Mucosal vaccine delivery: current state and a pediatric perspective[J]. J Control Release, 2016, 240: 394-413. DOI:10.1016/j.jconrel.2016.02.014
[7]
FUJIMOTO K, UEMATSU S. Development of prime-boost-type next-generation mucosal vaccines[J]. Int Immunol, 2020, 32(9): 597-603. DOI:10.1093/intimm/dxz085
[8]
LONGET S, LUNDAHL M L E, LAVELLE E C. Targeted strategies for mucosal vaccination[J]. Bioconjugate Chem, 2018, 29(3): 613-623. DOI:10.1021/acs.bioconjchem.7b00738
[9]
MIQUEL-CLOPÉS A, BENTLEY E G, STEWART J P, et al. Mucosal vaccines and technology[J]. Clin Exp Immunol, 2019, 196(2): 205-214. DOI:10.1111/cei.13285
[10]
AOSHI T. Modes of action for mucosal vaccine adjuvants[J]. Viral Immunol, 2017, 30(6): 463-470. DOI:10.1089/vim.2017.0026
[11]
SUN B N, YU S, ZHAO D Y, et al. Polysaccharides as vaccine adjuvants[J]. Vaccine, 2018, 36(35): 5226-5234. DOI:10.1016/j.vaccine.2018.07.040
[12]
WAN X H, YIN Y M, ZHOU C Z, et al. Polysaccharides derived from Chinese medicinal herbs: a promising choice of vaccine adjuvants[J]. Carbohydr Polym, 2022, 276: 118739. DOI:10.1016/j.carbpol.2021.118739
[13]
徐书雯. 胞内pH敏感型黄芪多糖PLGA纳米粒作为抗原佐剂的研究[D]. 南京: 南京农业大学, 2019.
XU S W. Study on the intracellular pH-responsive astragalus polysaccharide-encapsulated PLGA nanoparticles as adjuvant for antigens[D]. Nanjing: Nanjing Agricultural University, 2019. (in Chinese)
[14]
刘振广. 灵芝多糖脂质体和脂质立方液晶纳米粒免疫增强作用的研究[D]. 南京: 南京农业大学, 2018.
LIU Z G. Study on immunological enhancement activity of ganoderma lucidum polysaccharide liposome and cubosome[D]. Nanjing: Nanjing Agricultural University, 2018. (in Chinese)
[15]
罗莉. 山药多糖PLGA纳米粒的制备及其免疫增强作用的研究[D]. 南京: 南京农业大学, 2017.
LUO L. Study on preparation and immunological enhancement activity of Chinese Yam polysaccharide PLGA nanoparticles[D]. Nanjing: Nanjing Agricultural University, 2017. (in Chinese)
[16]
CHEN X Y, HAN W W, WANG G X, et al. Application prospect of polysaccharides in the development of anti-novel coronavirus drugs and vaccines[J]. Int J Biol Macromol, 2020, 164: 331-343. DOI:10.1016/j.ijbiomac.2020.07.106
[17]
KWAK M, YU K, LEE P C W, et al. Rehmannia glutinosa polysaccharide functions as a mucosal adjuvant to induce dendritic cell activation in mediastinal lymph node[J]. Int J Biol Macromol, 2018, 120: 1618-1623. DOI:10.1016/j.ijbiomac.2018.09.187
[18]
LIAO L Y, LI J, LI J, et al. Effects of Astragalus polysaccharides on intestinal morphology and intestinal immune cells of Muscovy ducklings infected with Muscovy duck reovirus[J]. Poult Sci, 2021, 100(1): 64-72. DOI:10.1016/j.psj.2020.10.021
[19]
任广明. 香菇多糖的硒化及其对慢性胰腺炎小鼠肠道菌群的影响[D]. 哈尔滨: 东北农业大学, 2016.
REN G M. Research on selenylation of lentinan and it's effects on gut microbiota in chronic pancreatitis mice[D]. Harbin: Northeast Agricultural University, 2016. (in Chinese)
[20]
赵明明. 黑灵芝多糖对小鼠肠道黏膜免疫及黏膜损伤的影响[D]. 南昌: 南昌大学, 2018.
ZHAO M M. Effect of polysaccharide from Ganoderma atrum on intestinal mucosal immunity and mucosal injury in mice[D]. Nanchang: Nanchang University, 2018. (in Chinese)
[21]
LIU C, LUO J, XUE R Y, et al. The mucosal adjuvant effect of plant polysaccharides for induction of protective immunity against Helicobacter pylori infection[J]. Vaccine, 2019, 37(8): 1053-1061. DOI:10.1016/j.vaccine.2018.12.066
[22]
谭西, 周欣, 陈华国. 多糖结构修饰研究进展[J]. 食品工业科技, 2019, 40(4): 341-349, 356.
TAN X, ZHOU X, CHEN H G. Research progress on structural modification of polysaccharides[J]. Science and Technology of Food Industry, 2019, 40(4): 341-349, 356. (in Chinese)
[23]
HUANG G L, HUANG H L. The derivatization and antitumor mechanisms of polysaccharides[J]. Future Med Chem, 2017, 9(16): 1931-1938. DOI:10.4155/fmc-2017-0132
[24]
CHENG L Z, WANG Y F, HE X X, et al. Preparation, structural characterization and bioactivities of Se-containing polysaccharide: a review[J]. Int J Biol Macromol, 2018, 120: 82-92. DOI:10.1016/j.ijbiomac.2018.07.106
[25]
BO R N, JI X, YANG H F, et al. The characterization of optimal selenized garlic polysaccharides and its immune and antioxidant activity in chickens[J]. Int J Biol Macromol, 2021, 182: 136-143. DOI:10.1016/j.ijbiomac.2021.03.197
[26]
金清. 黄芪多糖协同硫酸化淫羊藿多糖增强仔猪免疫的作用研究[D]. 荆州: 长江大学, 2020.
JIN Q. Astragalus polysaccharides synergize sulfated epimedium polysaccharides to enhance piglet immunity[D]. Jingzhou: Yangtze University, 2020. (in Chinese)
[27]
DEWANGAN H K. Rational application of nanoadjuvant for mucosal vaccine delivery system[J]. J Immunol Methods, 2020, 481-482: 112791. DOI:10.1016/j.jim.2020.112791
[28]
KANEKO K, MCDOWELL A, ISHII Y, et al. Liposomal α-galactosylceramide is taken up by gut-associated lymphoid tissue and stimulates local and systemic immune responses[J]. J Pharm Pharmacol, 2017, 69(12): 1724-1735. DOI:10.1111/jphp.12814
[29]
周兆海, 梁浩钊, 陈刚, 等. 玉屏风多糖脂质体对雏鸡黏膜免疫的影响[J]. 动物医学进展, 2019, 40(10): 54-59.
ZHOU Z H, LIANG H Z, CHEN G, et al. Effect of Yupingfeng polysaccharide liposomes on mucosal immunity of chicks[J]. Progress in Veterinary Medicine, 2019, 40(10): 54-59. DOI:10.3969/j.issn.1007-5038.2019.10.011 (in Chinese)
[30]
梁浩钊, 吴春琼, 李樵锋, 等. 玉屏风多糖脂质体对雏鸡肠黏膜及淋巴组织形态结构的影响[J]. 动物医学进展, 2020, 41(11): 84-89.
LIANG H Z, WU C Q, LI Q F, et al. Effect of yupingfeng polysaccharides liposomes on morphology and structure of intestinal mucosa-associated lymphoid tissue in chicks[J]. Progress in Veterinary Medicine, 2020, 41(11): 84-89. DOI:10.3969/j.issn.1007-5038.2020.11.016 (in Chinese)
[31]
SINGH B, MAHARJAN S, CHO K H, et al. Chitosan-based particulate systems for the delivery of mucosal vaccines against infectious diseases[J]. Int J Biol Macromol, 2018, 110: 54-64. DOI:10.1016/j.ijbiomac.2017.10.101
[32]
MEHRABI M, MONTAZERI H, DOUNIGHI N M, et al. Chitosan-based nanoparticles in mucosal vaccine delivery[J]. Arch Razi Inst, 2018, 73(3): 165-176.
[33]
LI D, FU D W, KANG H, et al. Advances and potential applications of chitosan nanoparticles as a delivery carrier for the mucosal immunity of vaccine[J]. Curr Drug Deliv, 2017, 14(1): 27-35. DOI:10.2174/1567201813666160804121123
[34]
KUMAR A, VIMAL A, KUMAR A. Why Chitosan?From properties to perspective of mucosal drug delivery[J]. Int J Biol Macromol, 2016, 91: 615-622. DOI:10.1016/j.ijbiomac.2016.05.054
[35]
KOUR P, RATH G, SHARMA G, et al. Recent advancement in nanocarriers for oral vaccination[J]. Artif Cells, Nanomed, Biotechnol, 2018, 46(S3): S1102-S1114.
[36]
史同瑞, 刘宇, 王爽, 等. 现代中药发酵技术及其优势[J]. 中兽医学杂志, 2014(1): 51-54.
SHI T R, LIU Y, WANG S, et al. Modern Chinese medicine fermentation technology and its advantages[J]. Chinese Journal of Traditional Veterinary Science, 2014(1): 51-54. DOI:10.3969/j.issn.1003-8655.2014.01.029 (in Chinese)
[37]
梁子敬. 发酵黄芪多糖的结构表征及其对小鼠肠道黏膜免疫的改善作用[D]. 北京: 中国农业科学院, 2019.
LIANG Z J. Structural characterization of fermented Astragalus membranaceus polysaccharides and its improvement effect on intestinal mucosal immunity in mice[D]. Beijing: Chinese Academy of Agricultural Sciences, 2019. (in Chinese)
[38]
LI S, WANG X F, REN L N, et al. Protective effects of γ-irradiated Astragalus polysaccharides on intestinal development and mucosal immune function of immunosuppressed broilers[J]. Poult Sci, 2019, 98(12): 6400-6410. DOI:10.3382/ps/pez478
[39]
CAMILLERI M, MADSEN K, SPILLER R, et al. Intestinal barrier function in health and gastrointestinal disease[J]. Neurogastroenterol Motil, 2012, 24(6): 503-512. DOI:10.1111/j.1365-2982.2012.01921.x
[40]
李任军, 王海梅, 胡松华. 补益类中药对动物肠黏膜免疫的调节作用[J]. 中兽医医药杂志, 2019, 38(4): 26-28.
LI R J, WANG H M, HU S H. Reviewed on immunoregulation of traditional Chinese medicine with tonifying effect on animal intestinal mucosal immune[J]. Journal of Traditional Chinese Veterinary Medicine, 2019, 38(4): 26-28. (in Chinese)
[41]
GEHART H, CLEVERS H. Tales from the crypt: new insights into intestinal stem cells[J]. Nat Rev Gastroenterol Hepatol, 2019, 16(1): 19-34. DOI:10.1038/s41575-018-0081-y
[42]
SEIKRIT C, PABST O. The immune landscape of IgA induction in the gut[J]. Semin Immunopathol, 2021, 43(5): 627-637. DOI:10.1007/s00281-021-00879-4
[43]
王翌, 李淼, 孙元, 等. 靶向M细胞的抗原递送——增强黏膜免疫应答的关键策略[J]. 生物工程学报, 2019, 35(2): 216-225.
WANG Y, LI M, SUN Y, et al. Microfold cells-targeting antigen delivery: a promising strategy to enhance the efficacy of mucosal vaccines[J]. Chinese Journal of Biotechnology, 2019, 35(2): 216-225. (in Chinese)
[44]
OH S H, KIM S H, JEON J H, et al. Cytoplasmic expression of a model antigen with M Cell-Targeting moiety in lactic acid bacteria and implication of the mechanism as a mucosal vaccine via oral route[J]. Vaccine, 2021, 39(30): 4072-4081. DOI:10.1016/j.vaccine.2021.06.010
[45]
KOMBAN R J, STRÖMBERG A, BIRAM A, et al. Activated Peyer's patch B cells sample antigen directly from M cells in the subepithelial dome[J]. Nat Commun, 2019, 10(1): 2423. DOI:10.1038/s41467-019-10144-w
[46]
JIANG Y P, LI X L, WU Y, et al. Effect of Lentinan on Peyer's patch structure and function in an immunosuppressed mouse model[J]. Int J Biol Macromol, 2019, 137: 169-176. DOI:10.1016/j.ijbiomac.2019.06.206
[47]
XIE S Z, LIU B, YE H Y, et al. Dendrobium huoshanense polysaccharide regionally regulates intestinal mucosal barrier function and intestinal microbiota in mice[J]. Carbohydr Polym, 2019, 206: 149-162. DOI:10.1016/j.carbpol.2018.11.002
[48]
JIN M L, ZHU Y M, SHAO D Y, et al. Effects of polysaccharide from mycelia of Ganoderma lucidum on intestinal barrier functions of rats[J]. Int J Biol Macromol, 2017, 94: 1-9. DOI:10.1016/j.ijbiomac.2016.09.099
[49]
YING M X, ZHENG B, YU Q, et al. Ganoderma atrum polysaccharide ameliorates intestinal mucosal dysfunction associated with autophagy in immunosuppressed mice[J]. Food Chem Toxicol, 2020, 138: 111244. DOI:10.1016/j.fct.2020.111244
[50]
PIETRZAK B, TOMELA K, OLEJNIK-SCHMIDT A, et al. Secretory IgA in intestinal mucosal secretions as an adaptive barrier against microbial cells[J]. Int J Mol Sci, 2020, 21(23): 9254. DOI:10.3390/ijms21239254
[51]
LI Y, JIN L, CHEN T X. The effects of secretory IgA in the mucosal immune system[J]. Biomed Res Int, 2020, 2020: 2032057.
[52]
GOMMERMAN J L, ROJAS O L, FRITZ J H. Re-thinking the functions of IgA+ plasma cells[J]. Gut Microbes, 2014, 5(5): 652-662. DOI:10.4161/19490976.2014.969977
[53]
KAETZEL C S. The polymeric immunoglobulin receptor: bridging innate and adaptive immune responses at mucosal surfaces[J]. Immunol Rev, 2005, 206(1): 83-99. DOI:10.1111/j.0105-2896.2005.00278.x
[54]
JOHANSEN F E, KAETZEL C S. Regulation of the polymeric immunoglobulin receptor and IgA transport: new advances in environmental factors that stimulate pIgR expression and its role in mucosal immunity[J]. Mucosal Immunol, 2011, 4(6): 598-602. DOI:10.1038/mi.2011.37
[55]
TURULA H, WOBUS C E. The role of the polymeric immunoglobulin receptor and secretory immunoglobulins during mucosal infection and immunity[J]. Viruses, 2018, 10(5): 237. DOI:10.3390/v10050237
[56]
SHAN C L, SUN B D, DALLOUL R A, et al. Effect of the oral administration of astragalus polysaccharides on jejunum mucosal immunity in chickens vaccinated against Newcastle disease[J]. Microb Pathog, 2019, 135: 103621. DOI:10.1016/j.micpath.2019.103621
[57]
BAI Y J, HUANG F, ZHANG R F, et al. Longan pulp polysaccharide protects against cyclophosphamide-induced immunosuppression in mice by promoting intestinal secretory IgA synthesis[J]. Food Funct, 2020, 11(3): 2738-2748. DOI:10.1039/C9FO02780G
[58]
谢天宇, 胡红莲, 高民. 肠黏膜免疫屏障及其保护措施[J]. 动物营养学报, 2014, 26(5): 1157-1163.
XIE T Y, HU H L, GAO M. Gut mucosal immune barrier and the protective measures[J]. Chinese Journal of Animal Nutrition, 2014, 26(5): 1157-1163. DOI:10.3969/j.issn.1006-267x.2014.05.005 (in Chinese)
[59]
丘富安, 任喆, 郑纪元, 等. 参芪多糖口服液对鸡空肠黏膜免疫功能的保护作用[J]. 中国兽医科学, 2017, 47(11): 1441-1449.
QIU F A, REN Z, ZHENG J Y, et al. Protective effects of Shenqi polysaccharide oral liquid on jejunal mucosal immunity in chickens[J]. Chinese Veterinary Science, 2017, 47(11): 1441-1449. (in Chinese)
[60]
NEURATH M F, FINOTTO S, GLIMCHER L H. The role of Th1/Th2 polarization in mucosal immunity[J]. Nat Med, 2002, 8(6): 567-573. DOI:10.1038/nm0602-567
[61]
VAN WIJK F, CHEROUTRE H. Intestinal T cells: facing the mucosal immune dilemma with synergy and diversity[J]. Semin Immunol, 2009, 21(3): 130-138. DOI:10.1016/j.smim.2009.03.003
[62]
OLIVARES-VILLAGÓMEZ D, VAN KAER L. Intestinal intraepithelial lymphocytes: sentinels of the mucosal barrier[J]. Trends Immunol, 2018, 39(4): 264-275. DOI:10.1016/j.it.2017.11.003
[63]
陈凌锋, 蔡旭滨, 檀新珠, 等. 太子参茎叶多糖对断奶仔猪肠道免疫功能、肠黏膜形态结构及盲肠内容物菌群的影响[J]. 动物营养学报, 2017, 29(3): 1012-1020.
CHEN L F, CAI X B, TAN X Z, et al. Effects of Radix pseudostellariae stem and leaf polysaccharide on intestinal immune function, intestinal mucosal morphology and cecum contents flora of weaned piglets[J]. Chinese Journal of Animal Nutrition, 2017, 29(3): 1012-1020. DOI:10.3969/j.issn.1006-267x.2017.03.035 (in Chinese)
[64]
牛祥云. 松花粉多糖对小鼠肠道微环境及溃疡性结肠炎的作用研究[D]. 泰安: 山东农业大学, 2021.
NIU X Y. Effects of Pinus Pollen Polysaccharides on Intestinal Microenvironment and Colitis in Mice[D]. Taian: Shandong Agricultural University, 2021. (in Chinese)
[65]
沙洲. 松花粉多糖对鸡肠道黏膜免疫的影响及巨噬细胞的免疫调节作用[D]. 泰安: 山东农业大学, 2021.
SHA Z. Effects of pine pollen polysaccharides on intestinal mucosal immunity of chickens and immunomodulatory of macrophages[D]. Taian: Shandong Agricultural University, 2021. (in Chinese)
[66]
BEKIARIS V, PERSSON E K, AGACE W W. Intestinal dendritic cells in the regulation of mucosal immunity[J]. Immunol Rev, 2014, 260(1): 86-101. DOI:10.1111/imr.12194
[67]
IWASAKI A. Mucosal dendritic cells[J]. Annu Rev Immunol, 2007, 25: 381-418. DOI:10.1146/annurev.immunol.25.022106.141634
[68]
SOLOFF A C, BARRATT-BOYES S M. Enemy at the gates: dendritic cells and immunity to mucosal pathogens[J]. Cell Res, 2010, 20(8): 872-885. DOI:10.1038/cr.2010.94
[69]
鹿秀云, 岳海洋, 刘億, 等. 黄芪多糖对结肠炎小鼠树突状细胞表面共刺激分子表达的调节作用[J]. 中成药, 2018, 40(10): 2296-2298.
LU X Y, YUE H Y, LIU Y, et al. Effects of Astragalus polysaccharide on the expression of costimulatory molecules in dendritic cells of colitis mice[J]. Chinese Traditional Patent Medicine, 2018, 40(10): 2296-2298. DOI:10.3969/j.issn.1001-1528.2018.10.037 (in Chinese)
[70]
ZHAO H M, WANG Y, HUANG X Y, et al. Astragalus polysaccharide attenuates rat experimental colitis by inducing regulatory T cells in intestinal Peyer's patches[J]. World J Gastroenterol, 2016, 22(11): 3175-3185. DOI:10.3748/wjg.v22.i11.3175
[71]
CHEN K, MAGRI G, GRASSET E K, et al. Rethinking mucosal antibody responses: IgM, IgG and IgD join IgA[J]. Nat Rev Immunol, 2020, 20(7): 427-441. DOI:10.1038/s41577-019-0261-1
[72]
CHEN Q Q, REN R R, ZHANG Q Q, et al. Coptis chinensis Franch polysaccharides provide a dynamically regulation on intestinal microenvironment, based on the intestinal flora and mucosal immunity[J]. J Ethnopharmacol, 2021, 267: 113542. DOI:10.1016/j.jep.2020.113542
[73]
YING M X, YU Q, ZHENG B, et al. Cultured Cordyceps sinensis polysaccharides modulate intestinal mucosal immunity and gut microbiota in cyclophosphamide-treated mice[J]. Carbohydr Polym, 2020, 235: 115957. DOI:10.1016/j.carbpol.2020.115957
[74]
陶未来, 刘佳, 刘琼丹, 等. 术苦芩总多糖对湿热泄泻仔猪肠道菌群和免疫功能的影响[J]. 畜牧兽医学报, 2022, 53(3): 913-924.
TAO W L, LIU J, LIU Q D, et al. Effects of total polysaccharides from Zhukuqin on intestinal flora and immune function in piglets with dampness-heat diarrhea[J]. Acta Veterinaria et Zootechnica Sinica, 2022, 53(3): 913-924. (in Chinese)
[75]
HUANG C, CAO X Y, CHEN X F, et al. A pectic polysaccharide from Ligusticum chuanxiong promotes intestine antioxidant defense in aged mice[J]. Carbohydr Polym, 2017, 174: 915-922. DOI:10.1016/j.carbpol.2017.06.122

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