枸杞多糖免疫调节作用的实验研究

枸杞子主产于我国宁夏、甘肃、青海等地,是传统的名贵中药,具有滋补肝肾、益精明目和强壮机体的作用。枸杞多糖作为枸杞子的主要成分,具有抗肿瘤、抗衰老、抗疲劳等多种作用〔1〕。本文采用小鼠碳粒廓清实验,刀豆蛋白A(ConA)诱导小鼠脾淋巴细胞转化试验、溶血素实验对广夏枸杞汁的免疫调节功能进行了检测。报告如下。1　材料与方法1.1　材料1.1.1　雌性昆明种小鼠　体重18～22g。湖北省医学科学院实验动物中心提供(动物批准号:鄂动医管字19-007号)。1.1.2　枸杞多糖　由武汉广夏枸杞开发有限公司提供的广夏枸杞汁,内含枸杞多糖15g/L。1.1.…     

板蓝根多糖作为疫苗佐剂的初步研究进展

板蓝根是清热解毒的常用中药,临床常用于治疗病毒及细菌感染,其多糖是重要的活性成分之一.研究表明,板蓝根多糖具有显著的佐剂作用,并且不良反应少,有望成为未来疫苗佐剂的较佳选择.本文介绍了板蓝根多糖的提取和纯化方法、结构与组成的研究进展,并对板蓝根多糖的佐剂机制和作为疫苗佐剂的动物实验研究方面进行综述,为未来新型多糖佐剂的...     

黄芪多糖的抗肿瘤作用及其机制研究进展

黄芪多糖(Astragalus Polysaccharide,APS)是一种具有多重功效的天然提取物,具有抗肿瘤功效,研究价值和经济价值很高。本文就黄芪多糖的抗肿瘤功效及抗肿瘤机制的最新研究进展进行综述,可望对黄芪多糖在临床抗肿瘤方面的应用提供理论依据。     

中药多糖的免疫调节与抗肿瘤作用研究进展

肿瘤依然是严重威胁人类生命健康的一类常见病和多发病,目前尚无通用和特异的肿瘤治疗方法。恶性肿瘤治疗方法的探索依然是医学及其相关领域研究的热点。上世纪50年代发现中药多糖具有免疫作用以来,国内外学者就中药多糖免疫调节及其抗肿瘤作用开展了大量研究。本文着重从中药多糖对细胞免疫、体液免疫和免疫细胞因子的影响等方面综述了中药多糖的免疫及其抗肿瘤作用的研究。     

黄芪多糖对LAK细胞毒的增强作用

本文采用乳酸脱氢酶(LDH释放法研究了黄芪多糖(APS)对淋巴因子活化的杀伤细胞(LAK)的增强作用。结果表明:APS具有明显的增强LAK细胞毒作用,有效剂量范围为0.001mg/ml～0.01mg/ml,在0.01mg/ml呈最大的增强作用,为原LAK细胞毒性的3倍。同时也证实黄芪水煎剂本身也具有一定的增强作用。     

伤寒Vi多糖疫苗在我国的研究与应用现状

伤寒是严重影响我国人民健康的常见肠道传染病,研究和使用疫苗无疑是预防伤寒的有效手段。伤寒Vi多糖疫苗是一种目前被国内外公认为安全、有效的疫苗,并被WHO推荐使用。本文就我国在伤寒Vi多糖疫苗的稳定性、安全性与免疫效果等方面的研究与应用现状进行综述。     

肺炎链球菌多糖疫苗在高风险成人中的应用

肺炎链球菌多糖疫苗(PPV)用于肺炎链球菌性疾病发病风险较高的2岁及以上儿童和成人预防肺炎链球菌性疾病。肺炎链球菌性疾病已经成为严重威胁人类健康的疾病之一,肺炎链球菌耐药性增加和耐药菌株的广泛传播,加大了肺炎链球菌性疾病的治疗难度,因此在高风险人群中推广接种肺炎链球菌疫苗具有重大的公共卫生意义。2012年中华预防医学会发布了《肺炎链球菌性疾病相关疫苗应用技术指南(2012版)》,将疫苗防治对象扩大到成人和老人。在我国,肺炎链球菌疫苗为第二类疫苗,尚未进入国家免疫规划,肺炎链球菌多糖疫苗在高风险成人中的应用才刚起步。本文就肺炎链球菌多糖疫苗在高风险成人中的应用现状进行综述,以供今后推进相关工作参考。     

黄芪多糖毒性实验研究

[目的]对黄芪多糖的急性毒性、致突变性及30 d喂养进行研究. [方法]按<品安全性毒理学评价程序和方法>小鼠的急性毒性、小鼠骨髓细胞微核试验、小鼠精子畸形试验、大鼠30 d喂养试验及Ames试验进行了检测. [结果]小鼠MTD>15 000 mg/kg.bw,小鼠骨髓细胞微核试验和小鼠精子畸形试验测试组和对照组间均无统计学差异,Ames试验中不同剂量组在加S9和不加S9条件下的回变菌落数均未超过空白对照组回变菌落数的2倍.大鼠30 d喂养试验显示,各剂量组动物生长发育良好,血液及生化指标均在正常范围内,各试验组与对照组相比无统计学差异,病理学检查肝、肾、胃、肠均正常. [结论]黄芪多糖属无毒物,致突变试验及30 d喂养试验均为阴性.     

西洋参多糖对钴-60辐照小鼠的免疫调节作用

目的探讨西洋参多糖对钴-60γ射线照射致小鼠免疫抑制模型的免疫调节作用,并初步探讨其作用机制。方法将180只6～8周龄、18～22 g的雌性BALB/c小鼠随机分为5组:空白对照组、模型对照组和3个西洋参多糖剂量组(50mg/kg BW、100mg/kg BW和200mg/kg BW)。除空白对照组外,其余4组于d45,一次性接受全身照射(γ射线总剂量为4Gy)。3 d后,测定脾脏T淋巴细胞增殖能力、迟发型变态反应程度和碳粒廓清实验,测定血清丙二醛水平、超氧化物歧化酶活性和谷胱甘肽过氧化物酶活性。结果西洋参多糖在3个剂量组均能明显升高小鼠T淋巴细胞的增殖能力和迟发型变态反应程度,在100mg/kg BW和200mg/kg BW组能明显增高小鼠碳粒廓清指数,在3个剂量组均能明显降低小鼠血清中MDA水平,在50mg/kg BW组能明显增高小鼠血清SOD活性,小鼠血清GSH-Px活性差异无统计学意义。结论西洋参多糖能增强钴-60γ射线照射致免疫抑制小鼠免疫功能,可能通过减轻氧化应激对免疫系统的损害来实现。     

肺炎球菌多糖结合疫苗研究进展

人类为降低肺炎球菌感染导致的健康和经济双重负担已经奋斗了两个世纪.肺炎球菌导致的侵袭性肺炎球菌疾病(Invasive pneumococcal disease,IPD)、脑膜炎和急性中耳炎等,在全球范围内可发生,而且以婴幼儿和老年人高发.肺炎球菌对多数抗生素耐药,疫苗是控制肺炎球菌流行的最有效措施.科学家们从20世纪初...     

Artesunate enhances the immune response of rabies vaccine as an adjuvant

Rabies is an ancient zoonosis that continues to be an important health problem worldwide. Vaccination with rabies vaccine is the most important strategy to prevent rabies. Adjuvants contribute to the immune response of viral vaccine. The aim of this study was to investigate whether artemisinin derivatives artesunate and dihydroartemisinin could enhance the immunogenicity of inactivated rabies virus in mice. Administration of artesunate or dihydroartemisinin by intramuscular injection at a dose of 5 mg/kg did not cause body weight loss and unusual symptoms in mice. Mice were immunized with inactivated CVS-11 or inactivated rHEP-dG together with either artesunate or dihydroartemisinin through intramuscular injection. Blood samples were collected to investigate the virus-neutralizing antibody (VNA) titers, and challenge assays were then conducted. The results showed that the rabies VNA titers in mice co-treated with artesunate rather than dihydroartemisinin were significantly higher than in the control animals treated with the phosphate buffered saline (PBS). In addition, mice co-treated with artesunate survived from lethal rabies virus challenge compared with those treated with PBS. In contrast, co-treatment with dihydroartemisinin did not improve the survival rate of the challenged mice. The findings indicate that artesunate could be used as a new candidate adjuvant for rabies vaccination.     

Delta inulin polysaccharide adjuvant enhances the ability of split-virion H5N1 vaccine to protect against lethal challenge in ferrets

Background

The reduced immunogenicity of the H5 hemagglutinin (HA), compared to seasonal HA serotypes, has stimulated searches for effective adjuvants to improve H5 vaccine efficacy. This study examined the immunogenicity and protective efficacy in ferrets immunized with a split-virion H5N1 vaccine combined with Advax™, a novel delta inulin-based polysaccharide adjuvant technology that has previously demonstrated ability to augment humoral and cellular immunity to co-administered antigens.

Methods

Ferrets were vaccinated twice 21 days apart with 7.5 μg or 22.5 μg of a split-virion preparation of A/Vietnam/1203/2004 with or without adjuvant. An additional group received just one immunization with 22.5 μg HA plus adjuvant. Serum antibodies were measured by hemagglutination inhibition and microneutralization assays. Vaccinated animals were challenged intranasally 21 days after the last immunization with 10⁶ EID₅₀ of the homologous strain. Morbidity was assessed by observed behavior, weight loss, temperature, cytopenias, histopathology, and viral load.

Results

No serum neutralization antibody was detected after two immunizations with unadjuvanted vaccine. Two immunizations with high or low dose adjuvanted vaccine stimulated high neutralizing antibody titers. Survival was 100% in all groups receiving adjuvanted-vaccine including the single dose group, compared to 67% survival with unadjuvanted vaccine, and 0% survival in saline or adjuvant-alone controls. Minimal morbidity was seen in all animals receiving adjuvanted vaccine, and was limited to rhinorrhea and mild thrombocytopenia, without fever, weight loss, or reduced activity. H5N1 virus was cleared from the nasal wash by day 4 post-challenge only in animals receiving adjuvanted vaccine which also prevented viral invasion of the brain in most animals.

Conclusions

In this initial study, Advax™ adjuvant formulations improved the protective efficacy of a split-virion H5N1vaccine as measured by significantly enhanced immunogenicity, survival, and reduced morbidity.     

Bovine immune response to leptospira antigen in different novel adjuvants and vaccine delivery platforms

Leptospirosis is a global zoonosis causing significant economic losses for cattle production. Current cattle vaccines against leptospirosis need improvement to provide efficacy against multiple serovars, reduce shedding in urine, and to induce earlier and more robust immune responses. In this study, Leptospira borgpetersenii serovar Hardjo strain 203 antigen was combined with novel adjuvants (a biodegradable polyanhydride compressed rod implant (VPEAR), poly(diaminosulfide) microparticles, a water-oil-water emulsion adjuvant, and aluminum hydroxide) to develop novel vaccines. Cattle were immunized twice, at a 4 week interval, with inoculums containing adjuvants alone or leptospira antigens and immune responses were compared to responses of cattle receiving a commercial monovalent leptospirosis vaccine (Spirovac). All animals were inoculated with a single dose of Spirovac at 20 weeks to assess antigen recall responses. Serum antibody responses were increased (P > 0.05) at 8 and 20 weeks after vaccination in cattle receiving inoculums containing leptospira antigens combined with water-oil-emulsion, poly(diaminosulfide) microparticles (PNSN-MP), or aluminum hydroxide and in cattle vaccinated with Spirovac. Humoral responses were predominantly IgG1 isotypes. Antigen-specific proliferative responses were detected after initial vaccination in cattle vaccinated with Spirovac, PNSN-MP and water-oil-water treatments. Most proliferative responses occurring within CD4+ and gamma delta T cell populations expressing CD45RO and CD25 markers, a response consistent with an effector memory phenotype. Antigen-specific immune responses were not detected in cattle vaccinated with VPEAR after initial inoculation, but were detected in the antigen recall responses. PBMCs from cattle vaccinated with Spirovac, oil-water-oil, or PNSN-MP treatments had increased (P < 0.05) IL-17A release after in vitro stimulation with leptospirosis antigens, whereas all groups produced IFN-γ and IL-17A after in vitro stimulation during the antigen recall response. Our data demonstrates that combining leptospirosis antigens with these adjuvants enhances immunogenicity in cattle.Interpretative Summary: Vaccination of livestock is a key mechanism for minimizing transmission of leptospirosis, a zoonotic disease. Leptospirosis vaccines for cattle need to be improved to provide greater levels of protection from kidney colonization, better immune responses, and protection against multiple serovars. This could be accomplished using new vaccine adjuvants. In this study, several novel adjuvants were evaluated for their ability to induce effective immune responses in cattle to leptospira antigens as compared to currently available vaccines. Data suggested that vaccines containing biodegradable polymer microparticles and oil-emulsion adjuvants induced similar or greater immune responses as compared to a commercial vaccine. Our data suggest these new vaccine formulations warrant further investigation as new vaccine formulations for cattle and other livestock.     

Enhanced immune responses of foot-and-mouth disease vaccine using new oil/gel adjuvant mixtures in pigs and goats

The immunity and protective capability produced by vaccines can vary remarkably according to the kinds of adjuvants being used. In the case of foot-and-mouth disease (FMD) vaccines in pigs, only oil-adjuvant vaccines have been used, and these tend to show lower immunity in pigs than in cattle. New adjuvants for these vaccines are therefore needed. We made different experimental FMD vaccines using new adjuvants (ISA 201, Carbigen, Emulsigen-D) and well-known adjuvants (ISA 206, aluminum hydroxide gel) and then conducted tests to compare the enhancement in pig immunity. More effective immune responses and protection against challenge were observed with the new adjuvants Emulsigen-D and ISA 201 compared to existing adjuvants. In the case of dairy goats, a mixture of Emulsigen-D and aluminum hydroxide gel produced rapid neutralizing antibody responses that were similar to results from tests conducted with pigs.     

CpG oligodeoxynucleotides containing GACGTT motifs enhance the immune responses elicited by a goose parvovirus vaccine in ducks

Recombinant parvovirus VP2 (rVP2) was formulated with different types of adjuvant, including aluminum adjuvant and CpG oligodeoxynucleotides (ODNs), and the immunological responses after vaccination in ducks were examined. In comparison with the control group, production of rVP2-specific antibodies, expression of cytokines in peripheral blood mononuclear cells (PBMC) stimulated by rVP2, and percentage of CD4(+)/CD8(+) cells in PBMC were significantly increased in ducks immunized with rVP2 formulated with CpG ODNs containing 3 copies of GACGTT motif. CpG ODNs with GACGTT motifs might be used to improve the efficacy of vaccines for ducks.     

Flagellin enhances tumor-specific CD8 T cell immune responses through TLR5 stimulation in a therapeutic cancer vaccine model

Tumor antigen (TA)-specific immunotherapy is an emerging approach for cancer treatment. Potent adjuvants are prerequisites to the immunotherapy for overcoming the low immunogenicity of TAs. We previously demonstrated that a bacterial flagellin, Vibrio vulnificus FlaB, has potent adjuvant activity in various vaccination models. In this study, we investigated whether the FlaB protein could be a potent adjuvant for a human papillomavirus 16 E6 and E7 (E6/E7) peptide-based anticancer immunotherapy. We used an E6/E7-expressing TC-1 carcinoma implantation animal model and tested TA-specific immunomodulation by FlaB. We co-administered the E6/E7 peptide either with or without FlaB into TC-1 tumor-bearing mice and then analyzed the antitumor activity of the peptide. FlaB significantly potentiated specific antitumor immune responses elicited by the peptide immunization, as evidenced by retarded in vivo tumor growth and significantly prolonged survival. We noticed that TC-1 cells do not express Toll-like receptor 5 (TLR5) on their surface and the TLR5 signaling pathway in TC-1 cells was not responsible for the antitumor effect of FlaB. FlaB potentiated the CTL activity and Ag-specific IFN-γ production of CD8⁺ T cells from the draining lymph node and spleen. In addition, this antitumor activity was abrogated following the in vivo depletion of CD8⁺ T cells and in TLR5 knockout (KO) or MyD88 KO mice. These results suggest that flagellin could enhance TA-specific CD8⁺ CTL immune responses through TLR5 stimulation in cancer immunotherapy.     

Effects of astragalus polysaccharides on immunologic function of erythrocyte in chickens infected with infectious bursa disease virus

160 Haline white chickens at 25 days old, negative for antibody to infectious bursa disease virus (IBDV), were randomly allocated into four groups. Chickens in groups 2–4 were infected with 0.3 ml IBDV at 26 days old. Chickens in groups 3 and 4 were injected respectively with 5 and 10 mg astragalus polysaccharide (APS) for 6 consecutive days from the first day of infection. At 21, 29, 32, 35 and 38 days old, the blood samples were taken from heart, and erythrocyte-C_3b receptor rosette rate (E-C_3bRR), erythrocyte-C_3b immune complex rosette rate (E-ICRR), erythrocyte rosette forming enhancing rate (ERER) and erythrocyte rosette forming inhibitory rate (ERIR) were measured. The results showed that E-C_3bRR and ERER significantly declined in chicken infected with IBDV (p < 0.01); E-C_3bRR, E-ICRR and ERER in groups 3 and 4 treated with APS were higher than that in groups 1 and 2 (p < 0.01), the ERIR in groups 3 and 4 is similar to that in group 1. The results suggest that the immunological function of chicken erythrocytes declines after infected with IBDV and APS obviously enhances the immunological function of chicken erythrocytes.     

Frequencies of peripheral immune cells in older adults following seasonal influenza vaccination with an adjuvanted vaccine

As age increases, immune responses and consequently protection following vaccination to seasonal influenza is commonly believed to decrease. Possible drivers of this immune dysfunction include immunosenescence, repeated exposure to the same seasonal influenza antigens, and prior infection with cytomegalovirus (CMV). Here, to determine immune parameters distinguishing vaccine humoral responders (R) from non-responders (NR) following vaccination, we surveyed broad peripheral blood “cellular immune correlates” of older adults vaccinated with Fluad® (an adjuvanted subunit influenza vaccine containing strains H1N1, H3N2 and B). Phenotyping included αβ-T-cells, γδ-T-cells, B-cells and myeloid cells. The frequencies of most of these lymphocyte phenotypes were found to be similar in R and NR, although perhaps counterintuitively, one of the few differences seen between the two groups was higher frequencies of regulatory T-cells in R. These differences were more prominent for responses to the vaccine strains H1N1 and H3N2 than to the B strain, and in CMV-seropositive than CMV-seronegative elderly. Further, frequencies of early-differentiated CD4+ T-cells tended to be higher and frequencies of memory CD4+ T-cells tended to be lower in R than NR. There were also differences in B-cells, with higher frequencies in R compared to NR. To the best of our knowledge, these results are the first to report such differences in elderly people responding or failing to respond to adjuvanted seasonal influenza vaccination.