白及多糖通过调节免疫作用抑制结肠癌CT26荷瘤小鼠肿瘤生长

目的:研究白及多糖(BSP)对结肠癌CT26荷瘤小鼠的抗肿瘤及免疫调节作用.方法:从30只BALB/c小鼠中随机选取6只作为对照组(Control),剩余24只小鼠右前肢皮下接种CT26细胞构建CT26结肠癌小鼠模型,建模成功后将模型裸鼠分为荷瘤模型组(Model)、白及多糖低剂量组[BSP-L,100 mg/(kg·...     

马勃多糖对乳腺癌荷瘤小鼠肿瘤生长的抑制作用及可能机制

为探讨马勃多糖(Calvatia gigantea polysaccharide, CGP)对乳腺癌荷瘤小鼠肿瘤生长的抑制作用及潜在机制,给小鼠接种4T1细胞建立乳腺癌荷瘤模型,将建模成功的小鼠随机分为模型组、环磷酰胺组(25 mg/kg)和CGP高(200 mg/kg)、中(100 mg/kg)、低(50 mg/kg)剂量组,每组8只;另随机选取8只健康小鼠为对照组(给予生理盐水)。灌胃给药,1次/d,给药周期为14 d。给药结束后检测瘤重、脾脏指数、胸腺指数,血清细胞因子水平及PI3K/Akt/mTOR信号通路相关蛋白表达。结果发现,与模型组比较,CGP高、中、低剂量组小鼠瘤重均明显减轻(P0.05);与模型组比较,除CGP低剂量组小鼠胸腺指数外,各剂量组小鼠脾脏指数、胸腺指数、NK细胞增殖率、脾脏淋巴细胞增殖刺激指数及血清IFN-γ、IL-6、IL-2水平均明显增加(P0.05);与模型组比较,CGP高、中、低剂量组小鼠p-PI3K、p-Akt和p-mTOR的相对表达量均明显降低(P0.05)。以上结果提示CGP对乳腺癌荷瘤小鼠的肿瘤生长具有抑制作用,该作用与免疫调节及抑制PI3K/Akt/mTOR信号通路的激活有关。     

灵芝多糖抗肿瘤免疫调节机制的研究进展

灵芝多糖是灵芝水溶性提取物的主要生物活性成分.作为一种免疫调节剂对癌症患者具有明显的辅助治疗作用.灵芝多糖抗癌作用主要通过免疫调节、抗增殖、促凋亡、抗转移和抗血管生成的作用.本文综述了灵芝多糖调节机体固有免疫系统、T/B淋巴细胞及细胞因子等免疫机制发挥抗肿瘤作用.     

桑黄酸性多糖对D-半乳糖诱导小鼠的免疫调节作用研究

目的:探讨桑黄酸性多糖(PIP-A)对D-半乳糖(D-gal)诱导小鼠的免疫调节作用.方法:采取水提醇沉法提取桑黄总多糖(PIP),并利用DEAE-纤维素柱(7.5 cm×30 cm,CI型)进行分级,获得PIP-A并测定其单糖组成;采用D-gal(200 mg/kg)构建小鼠衰老模型,将小鼠随机分成4组,分别为空白组...     

白扁豆多糖对免疫抑制小鼠的免疫调节作用

目的探讨白扁豆多糖(polysaccharide from Dolichos lablab L.,DLP)对环磷酰胺(cyclophosphamide,CTX)所致的免疫抑制小鼠的免疫调节作用。方法小鼠随机分为正常对照组、模型组、香菇多糖(Lentinan,LNT,15 mg/kg)和白扁豆多糖低、中、高剂量组(75、150、300 mg/kg)。通过对小鼠连续3 d腹腔注射环磷酰胺(100 mg/kg)建立小鼠免疫抑制模型,造模后连续灌胃给药7 d,检测免疫器官重量指数、血清溶血素、脾淋巴细胞增殖、脾脏NK细胞活性及小鼠血清细胞因子IL-2、IL-4和INF-γ水平,观察白扁豆多糖的免疫调节作用。结果与正常对照组相比,模型组小鼠的免疫器官重量指数、血清溶血素、脾淋巴细胞增殖、脾脏NK细胞活性及小鼠血清细胞因子IL-2、IL-4和INF-γ水平均明显降低(P<0.05,P<0.01),而中、高剂量DLP和香菇多糖可明显减轻由环磷酰胺引起的上述各项指标的下降(P<0.05,P<0.01)。结论 DLP能改善环磷酰胺所致免疫抑制小鼠的免疫功能。     

海带硫酸多糖对小鼠腹腔巨噬细胞的免疫调节作用

近年来人们发现某些藻类多糖具有明显的抗肿瘤作用[1]。我们从海带中提取了一种天然生物大分子海带多糖(Ｌａｍｉｎａｒｉｎｓｕｌｆａｔｅ,ＬＡＳ),由Ｌ岩藻糖、Ｄ半乳糖等糖基组成的硫酸酯化多聚物,平均分子量为1.5×105。该多糖对小鼠肉瘤Ｓ180的抑制率可达86.5%。本研...     

黄芪及黄芪多糖对隐孢子虫感染小鼠的免疫调节作用

目的探讨黄芪及黄芪多糖对隐孢子虫感染的免疫抑制小鼠的免疫调节作用。结论 20日龄Balb/c小鼠连续8d灌服醋酸地赛米松后,于第9天经口接种1×106个隐孢子虫卵囊1次,建立隐孢子虫感染模型,再经黄芪水煎剂及黄芪多糖灌胃治疗10d,并设正常对照、模型对照和西药对照组。每日计数粪便隐孢子虫卵囊数量,组织切片HE染色后光学显微镜观察肠组织病理学改变,ELISA法检测血清IL-2、IL-4、IFN-γ水平,流式细胞仪检测T细胞亚群。结果与模型组比较,黄芪水煎剂组、黄芪多糖组和西药组小鼠卵囊排出数量减少,肠组织病理学改变较轻,免疫学检测发现CD4、CD4/CD8及IL-2、IL-4和IFN-γ水平明显升高（P〈0.05）。结论黄芪水煎剂及黄芪多糖通过增强免疫功能促进隐孢子虫感染小鼠恢复。     

分枝杆菌多糖免疫调节作用的研究

由非致病性分枝杆菌中提取出的多糖成分，命名为分枝杆菌多糖，动物实验表明，ＭＰＳ可增强小鼠巨噬细胞的吞噬杀伤活性；提高小鼠产生抗ＳＲｂｃ抗体能力；促进经环磷酰胺处理小鼠减少的白细胞迅速回升；回强小鼠造血祖细胞功能及提高其血清ＧＭ－ＣＳＦ水平。     

当归及其多糖对隐孢子虫感染小鼠的免疫调节作用

目的 探讨当归及当归多糖对隐孢子虫感染小鼠的免疫调节作用.方法 连续8 d灌服给小鼠醋酸地赛米松后,于第9 d经口接种1×10^6个隐孢子虫卵囊1次,建立隐孢子虫感染模型,再经当归水煎剂及当归多糖灌胃治疗10 d,计数粪便隐孢子虫卵囊,观察肠组织病理学改变,检测T细胞亚群和血清IL-2、IL-4、IFN-γ水平.并设正常对照、模型对照和西药对照组.结果 与模型组比较,西药组、当归水煎剂组和当归多糖组小鼠卵囊排除数量减少（第4天分别为300个、50个、238个和230个）,肠组织病理学改变较轻,免疫学检测发现CD4^＋T细胞[分别为（38.85±8.16）%、（47.98±11.90）%、（55.85±6.63）%、（51.43±8.42）%]CD4^＋/CD8^＋[分别为1.98±0.47、2.25±0.53、2.51±0.55、2.42±0.23）]及IL-2的水平[分别为（28.75 4±1.93）pg/ml、（69.02±10.47）ps/ml、（42.91±4.48）pg/ml、（40.90±0.79）pg/ml]IL-4的水平[分别为（42.00±6.79）pg/ml、（64.26±6.07）pg/ml、（58.31±9.13）ps/ml、（54.95±8.99）pg/ml]和IFN-γ的水平[分别为（28.73±8.71）ps/ml、（45.40±6.11）pg/ml、（84.40±7.63）pg/ml、（78.40±6.32）pg/ml]明显升高（F值分别为13.58、19.37、24.22、54.36和35.74 P值均小于0.05）.结论 当归水煎剂和当归多糖通过增强机体免疫功能促进隐孢子虫感染的免疫抑制小鼠的恢复.     

Prosaposin基因对TLR3信号途径的调节

目的 研究prosaposin基因对转录活性因子和免疫细胞表面分子表达的影响,分析该基因在各种Toll-like re-ceptor不同途径中的作用,初步探讨prosaposin基凼在免疫系统中的功能.方法 克隆prosaposin基因并建立prosaposin基因稳定转染的细胞系,通过检测报告基凶化学发光和用不同Toll-like receptor配体刺激后比较细胞表面分子的表达水平的方法 来探讨不同途径中该基因发挥的作用.结果 在TLR3配体PolyI:C刺激条件下,prosaposin基因能够明显促进对NF-IcB以及AP-1的活性,而且明显抑制细胞表面分子B7H1和PD1的表达.结论 prosaposin基因能够影响TLR3信号途径作用于免疫细胞,调节免疫相关细胞分子,可能在免疫系统方面起作用.     

云芝糖肽对人PBMC中TLR5信号通路调控机制的研究

目的:研究云芝糖肽(PSP)对人外周血单个核细胞(PBMC)中TLR5信号通路的调控作用,探索PSP对Toll样通路的免疫调节机制。方法:体外分离、培养人PBMC,分为对照组和PSP处理组,采用实时荧光定量PCR(Q-PCR)技术对PSP处理人PBMC前后,PBMC中的TLR5信号通路中相关基因的表达差异情况进行定量分析。结果:PSP处理的实验组与对照组相比较,TLR5信号通路中的TLR5、IRAK4、TRAF6、IRF5和NF-κB基因的表达水平均显著增高(P<0.05),但AP-1基因的表达降低(P<0.05)。结论:PSP对PBMC中TLR通路的调控可能主要通过NF-κB和IRF5调控终端效应因子来发挥免疫调节作用,这些为进一步探讨PSP的免疫调节作用机理提供了实验依据。     

Potential role of the TLR4/IRAK-4 signaling pathway in the pathophysiology of acute pancreatitis in mice

Objective and design  

Toll-like receptor 4 (TLR4) is potentially associated with acute pancreatitis (AP), but its exact role remains controversial. IL-1 receptor-associated kinase 4 (IRAK-4) is a common mediator of Toll-like receptors pathways, with an essential role in transducing downstream signals. This study investigates the potential role of the TLR4 pathway, in particular IRAK-4, in a murine model of AP.     

Immunomodulatory activity of butanol extract from Solanum lyratum in tumor-bearing mice

Solanum lyratum Thunb (Solanaceae) has been widely used for cancer as a folk remedy in Chinese traditional medicine. In this study, the main active fraction n-butanol extract from S. lyratum (BESL) was evaluated for the therapeutic efficacies on mice transplantable tumor and immunomodulatory potentials on the immune response in tumor-bearing mice. The effects of BESL on the growth of mouse transplantable S180 sarcoma, splenocyte proliferation, the activity of natural killer (NK) cells and cytotoxic T lymphocytes (CTL), production of cytokines from splenocytes, and serum antigen-specific antibody levels in S180-bearing mice were measured. BESL could not only significantly inhibit the growth of S180 sarcoma transplanted in mice, but also remarkably promote splenocytes proliferation, NK cell and CTL activity, interleukin-2 and interferon-γ production from splenocytes, and serum antigen-specific antibody levels in tumor-bearing mice (P?<?0.05, P?<?0.01, or P <0.001). The results suggested that BESL might exhibit antitumor activity by improving immune response, and it could act as antitumor agent with immunomodulatory activity. This study provided evidence to understand the therapeutic effects of S. lyratum for treatment of cancer and a natural product to further researches to be developed as a cancer chemopreventive agent.     

Immunomopharmacological effects of polysaccharides from Acanthopanax senticosus on experimental animals.

Polysaccharides PES isolated from a common Oriental herb Acanthopanax senticosus were found to have a wide spectrum of immunomodulatory activities on experimental animals. The potential usefulness of these polysaccharides is suggested in the observations that PES inhibited transplanted tumor growths and ameliorated toxicities of the toxic substances in experimental animals. Of most interest is the observations that they suppressed human TB propagation in mice and guinea pigs, as evaluated by lymph node responses and OT skin tests in the guinea pig model, and the quantitation of the TB in the lungs in the mouse model.     

A glycoprotein from Porphyra yezoensis produces anti-inflammatory effects in liposaccharide-stimulated macrophages via the TLR4 signaling pathway

The purpose of this study was to investigate the antioxidant and anti-inflammatory effects of a glycoprotein isolated from the alga Porphyra yezoensis in LPS-stimulated RAW 264.7 mouse macrophages. First, we extracted a novel material with antioxidant activity from P. yezoensis, confirmed by SDS-PAGE to be a glycoprotein, which we named P. yezoensis glycoprotein (PGP). PGP inhibited the production of NO and ROS and expression of iNOS, COX-2, TNF-α and IL-1β, which are involved in the pathogenesis of many inflammation-associated human diseases, including septic shock, hemorrhagic shock and rheumatoid arthritis. Next, we determined the mechanisms behind the antioxidant and anti-inflammatory activities of PGP. We focused on the Toll-like receptor 4 (TLR4) signaling pathway because it is well-known to induce the pro-inflammatory proteins that trigger MAPK and NF-κB activation in lipopolysaccharide (LPS)-induced oxidative events. PGP treatment reduced the formation of the TLR4-IRAK4 and TLR4-TRIF binding complexes in response to LPS. Moreover, it inhibited LPS-induced activation and nuclear translocation of NF-κB by abrogating IκB phosphorylation. PGP also suppressed the phosphorylation of ERK1/2 and JNK in a dose-dependent manner. These results suggest that PGP exerts its anti-inflammatory effects by modulating TLR4 signaling and thus inhibiting the activation of NF-κB and MAP kinases.     

锌指蛋白A20对Toll样受体信号途径的负反馈调控及其对机体的保护作用

Toll-like receptors (TLRs) recognize pathogens and initiate innate immune responses at the early stage of virus invasion, promoting the maturation and differentiation of immune cells, regulating immune respon-ses,and triggering inflammatory responses. Lipopolysaccharide (LPS) activates the TLR4 signaling pathways which result in the activation of NFκB and JNK/SAPK and the expression of large amounts of inflammatory fac-tors,leading to systemic inflammatory response and multiple organ failure. A20, a NFκB-dependant cytosolic protein, via a negative feedback loop blocks NFκB activation and participates in the regulation of inflammatory responses and the inhibition of apptosis;therefore, it provides protective effect on the body.