蛋白体佐剂及用于鼠疫F1-Ⅴ抗原的免疫效果

目的以蛋白体(proteosomes)佐剂,非共价结合鼠疫F1-V重组蛋白为免疫原,探讨滴鼻免疫BALB/c小鼠后诱导的免疫应答和免疫保护效果。方法佐剂与鼠疫F1-V重组蛋白为免疫原非共价结合,滴鼻免疫BALB/c小鼠4次后,采用间接ELISA检测血清特异性抗F1-V的IgG和IgA抗体及抗体亚型分类,并检测鼻咽、肺、小肠及阴道灌洗液中特异性抗F1-V的黏液分泌型IgA;并用流式细胞术检测鼻相关淋巴组织淋巴细胞、脾淋巴细胞、肠系膜淋巴结及小肠PP结T淋巴细胞表型的变化。第4次免疫后7d,用100 LD_(50)的鼠疫141强毒株进行腹腔攻毒。结果(1)以蛋白体为佐剂的鼠疫F1-V抗原与单纯的F1-V组相比,蛋白体疫苗组诱导血清IgG、IgA抗体显著升高(P<0.01),同时蛋白体疫苗组能诱导鼻咽、肺、小肠和阴道内多个黏膜部位特异性IgA抗体的产生,尤其是肺和生殖道冲冼液内抗体升高极为显著(P<0.01);(2)蛋白体疫苗组主要引起IgG1型抗体,主要诱导T_H2型免疫反应;(3)蛋白体疫苗组NALT和SP中CD4~ /CD8~ 比值比PBS对照有显著增高(P<0.01),MLN和PP中CD4~ /CD8~ 比值与PBS对照差异无统计学意义(P>0.05)。(4)小鼠在100 LD_(50)的鼠疫141强毒株腹腔攻毒后鼠疫F1-V重组蛋白组小鼠免疫保护率为0,而蛋白体佐剂疫苗组小鼠免疫保护率为67%。结论以自制的蛋白体为鼠疫F1-V抗原的佐剂滴鼻免疫小鼠,蛋白体不仅提高鼠疫F1-V抗原的系统免疫应答,而且能诱导小鼠呼吸道、消化道和生殖道局部黏膜免疫应答。蛋白体佐剂鼠疫疫苗对100 LD_(50)的鼠疫141强毒株腹腔攻毒具有一定的免疫保护作用,这为鼠疫黏膜疫苗的研制提供候选材料,也为鼠疫黏膜疫苗深入研究奠定了基础。     

不同佐剂与鼠疫F1-V融合重组蛋白抗原滴鼻免疫效果的研究

目的 研究不同佐剂与鼠疫F1-V融合重组蛋白抗原滴鼻免疫Balb/c小鼠,观察机体产生体液免疫和局部粘膜免疫反应的效果,为发展黏膜疫苗提供理论基础.方法 鼠疫F1-V融合重组蛋白抗原按比例分别与PorB(2类外膜蛋白)重组蛋白、蛋白体佐剂制备黏膜疫苗,滴鼻免疫Balb/c小鼠3次,取尾静脉血,采用ELISA检测血清IgG及抗体亚型分类,并检测鼻咽、肺、小肠及阴道灌洗液sIsA;采用FAC检测脾淋巴细胞表型的变化.结果 PorB重组蛋白佐剂疫苗组和蛋白体佐剂疫苗组较无佐剂组体液免疫抗体水平高、蛋白体佐剂疫苗组好于PorB重组蛋白佐剂疫苗组,但无显著性差异.结论 PorB重组蛋白佐剂疫苗和蛋白体佐剂疫苗均能诱导较强的系统免疫和黏膜免疫应答,且PorB重组蛋白佐剂疫苗免疫效果可与蛋白体佐剂疫苗相媲美,可进一步论证是否可用PorB重组蛋白佐剂替代蛋白体佐剂,这为鼠疫粘膜疫苗的研制奠定了基础.     

重组幽门螺杆菌尿素酶B亚单位疫苗鼻腔免疫的实验研究

目的:探讨基因工程疫苗Hp重组尿素酶B亚单位(rUreB)鼻腔接种的免疫效果。方法:以rUreB不同剂量或加不同佐剂滴鼻免疫BALB/c小鼠。末次免疫7 d后,收集血清及胃黏膜、小肠黏膜、鼻黏膜及气管黏膜冲洗液,用ELISA法检测抗rUreB特异性抗体。结果:rUreB鼻腔免疫后各实验组血清特异性IgG及各黏膜冲洗液中特异性IgA的水平均明显增高,与对照组相比较差异显著(P<0.01)。20μg剂量组与10μg剂量组相比较,仅血清特异性IgG水平增高,其它黏膜特异性IgA的水平未见增高。大肠杆菌不耐热肠毒素B亚单位(LTB)的佐剂效果较霍乱毒素B亚单位(CTB)强,卡泊波可增强鼻腔接种疫苗在胃黏膜洗液中的抗体应答水平。结论:CTB、LTB、卡泊波均可作为rUreB鼻腔黏膜接种的佐剂。HprUreB鼻黏膜接种,不仅可诱导血清特异性抗体反应,而且能引起多个黏膜部位的免疫应答,是一种方便、有效、廉价的免疫途径。     

空肠弯曲菌PEB1-LTB DNA疫苗构建及其对小鼠免疫保护性的研究

目的:研究粘膜佐剂大肠埃希菌不耐热肠毒素B亚单位(LTB)辅助的空肠弯曲菌(C.jejuni)外膜蛋白PEB1基因重组DNA疫苗诱导小鼠免疫应答水平。方法:构建pcDNA3.1(-)-PEB1-LTB真核重组表达载体,转染Hela细胞,Westernblot鉴定蛋白表达。滴鼻免疫BALB/c小鼠,末次免疫后2周,测定小鼠血清中IgG、IgA及气管、小肠粘膜冲洗液sIgA抗体;脾细胞培养上清中IFN-γ、IL-4水平。末次免疫后4周,采用空肠弯曲菌重复攻击的方式进行灌胃攻击,攻击后,根据动物疾病指数评价疫苗临床保护率。结果:构建的重组表达质粒能在Hela细胞内表达,重组蛋白。疫苗免疫小鼠后,不仅诱导了高水平血清IgG、IgA抗体,而且诱导了高水平粘膜sIgA抗体。其诱导的特异性免疫应答能有效保护免疫后小鼠免遭空肠弯曲菌的感染攻击。结论:构建的DNA疫苗经粘膜免疫能诱导小鼠产生较高水平的特异性免疫应答,能有效预防空肠弯曲菌感染。     

人轮状病毒抗原非复制型重组腺病毒黏膜免疫效果的研究

目的：对人轮状病毒抗原非复制型重组腺病毒诱导黏膜免疫的效果进行初步评价。方法：用表达轮状病毒VP7、VP6基因的3株重组腺病毒rvAdG1VP7(G)、rvAdG1VF7和rvAdVP6，分别通过灌胃和滴鼻两种途径对BALB／C小鼠进行2次免疫后，对肺灌洗液和肺、肠粘膜组织匀浆液中轮状病毒特异性的分泌型IgA(secretory IgA，SIgA)和local-IgG进行检测。结果：对肺灌洗液中特异性SIgA进行检测，发现滴鼻组的免疫学效果明显优于灌胃组。对肺、肠组织匀浆液中特异性IgA的分析表明，灌胃途径刺激异位粘膜组织产生免疫应答的能力较弱。对rvAdVP6滴鼻组小鼠肺灌洗液(1：20)特异性local-IgG和SIgA的阳转率进行比较，发现特异性local-IgG的应答水平明显高于特异性SIgA。结论：重组腺病毒可有效诱导针对轮状病毒的黏膜免疫。此研究为轮状病毒基因工程疫苗的免疫方案、免疫途径及免疫保护作用等的进一步研究莫定了基础。     

鼠疫菌重组质粒pcDNATE/F1-V的构建及其免疫效果的研究

目的 获得含有鼠疫F1和V抗原编码基因的重组质粒pcDNATE／E1-V,并测定其诱导特异性免疫应答的能力。方法PCR扩增鼠疫菌F1和V编码基因,分别与pGEM-T连接测序,构建pcDNATE／F1-V融合重组质粒,转染COS-7细胞,用Western blot方法鉴定目的蛋白的表达,重组质粒pcDNATE／E1-V加集落刺激因子(GM-CSF)免疫Balb／c小鼠,观察免疫效果。结果pcDNATE／F11-V在COS-7细胞中表达,免疫鼠体内产生特异性抗体,抗体亚型分析、细胞因子等指标的测定结果表明所构建DNA疫苗以诱发Th1型免疫为主。结论成功构建重组真核表达质粒pcDNATE／F1-V,其具有诱导特异性细胞免疫和体液免疫应答的能力,为鼠疫菌新型疫苗研制奠定了基础。     

高致病性人禽流感H5N1疫苗滴鼻免疫应答效果的初步研究

目的 通过高致病性人禽流感H5N1全病毒-MF59佐剂疫苗滴鼻免疫Balb/c小鼠,评价该疫苗所诱导的系统免疫与黏膜免疫应答效果.方法 以不同剂量抗原按比例与MF59佐剂配伍制成粘膜疫苗,滴鼻免疫Balb/c小鼠,二免2周采血检测血清IgG、IgM效价及血清中HAI(HA inhibitor)的中和抗体效价,同时收集鼻、肺灌洗液,检测其lgG和slgA抗体效价.结果 H5NI+MF59组血清抗体效价较H5NI组有显著升高(P＜0.01);在各剂量组中,随着剂量的增加抗体效价呈上升趋势.12μg腭后抗体效价呈下降趋势,以HSNI+MF59(12μg)组效价最高;肺鼻灌洗液中,均可检测到特异性分泌型IrA、IsG,其中特异性分泌型IgA效价略高于IgG;抗体亚型的分布以IgG1、IgG2b为主.结论 灭活高致病性禽流感全病毒H5N1在佐剂MF59作用下可诱导机体产生体液免疫应答,同时还可以在黏膜局部产生特异性分泌型IgA、IsG,为高致病人禽流感病毒I-15N1黏膜疫苗的研制奠定了基础.     

鼠疫组分疫苗诱导小鼠体液免疫应答研究

目的通过检测鼠疫组分疫苗免疫小鼠诱导的体液免疫应答,对其免疫原性进行评价。方法将小鼠随机分成4个实验组,免疫后5周内眦采血,检测血清中抗F1抗原和rV抗原IgG及IgA抗体;充分暴露气管,沿气管上端剪一楔形口,用PBS冲洗肺泡制备肺冲洗液,检测肺冲洗液中抗F1抗原和rv抗原IgG及IgA抗体。结果血清中可产生较高效价的抗F1抗原和rV抗原IgG抗体以及较低效价的抗F1抗原IgA抗体。肺冲洗液中可检测到抗F1抗原和rV抗原的IgG抗体,但无特异性IgA产生。结论鼠疫组分疫苗能诱导小鼠产生较强的血清抗体应答,肺冲洗液可检测到一定的IgG抗体,该疫苗有希望成为我国新一代鼠疫疫苗。     

免疫途径及侵袭蛋白表达对痢疾疫苗免疫效果影响的实验研究

目的探讨免疫途径及侵袭蛋白表达对2株痢疾疫苗免疫效果的影响.方法FSM-2117或FS-5416以4×107CFU/只分别经滴鼻、灌胃、肠内注射3种途径免疫小鼠,三免后7?d收集血清、小肠、鼻咽、肺、阴道冲洗液,ELISA法检测其中特异性福氏、宋内LPSIgA和IgG抗体(Ab)水平.结果滴鼻和肠内免疫都能够诱生血清中双价IgA、IgGAb显著升高,但仅滴鼻免疫组Ipa+株较Ipa-株升高显著(P＜0.01).滴鼻免疫组同时诱生鼻咽、肺、小肠内特异性抗体升高,尤其是生殖道冲洗液内抗体升高极为明显;而肠内免疫组诱生小肠、肺冲洗液内特异性抗体升高,但鼻咽及生殖道冲洗液内抗体未见明显升高.结论鼻粘膜免疫不仅诱导多个粘膜部位(特别是生殖道)的抗体反应,且能诱导系统免疫反应.是一个安全有效的免疫途径.研究中发现侵袭蛋白表达在鼻粘膜部位能够显著加强系统特异性抗体生成,但在胃肠粘膜却无此作用.     

HIV-1CN54 DNA疫苗滴鼻免疫小鼠诱发系统和黏膜免疫应答

目的：探讨重组痘苗病毒rVVsyngp120或rVVmCN54gp120候选疫苗是否增强HIV-1CN54合成gp120基因(syngp120)DNA疫苗的免疫原性。方法：第0、7、14、21天用DNA疫苗滴鼻免疫小鼠,第28、35、42天再滴鼻接种rVVsyngp120或rVVmCN54gp120。体外测脾和肠系膜淋巴结(MLN)淋巴细胞增殖应答与CD8^ CTL应答。测血清和黏膜洗液特异的IgG和IgA,并测其是否中和实验室适应株HIV-1SF33。结果：单纯DNA免疫后,脾和MLN淋巴细胞在体外发生增殖应答和CTL应答,且测出血清特异的IgG和黏膜洗液特异的IgA。重组痘苗病毒末次免疫后第2周(第56天),发现rVVmCN54gp120增强MLN淋巴细胞增殖应答和CTL应答,脾CTL应答也增强。rVVsyngp120则增强MLN CTL应答。同时发现：2组重组痘苗病毒免疫的动物其血清中特异IgG抗体滴度均有所增高,但黏膜(粪便和阴道)洗液特异IgA抗体滴度却未增高,未测出血清特异IgA和黏膜洗液特异IgG。免疫血清可中和HIV-1SF33,而阴道洗液却不能。结论：单纯DNA疫苗滴鼻免疫可诱发较弱的系统和黏膜体液免疫与细胞免疫,但维持时间短。重组痘苗病毒主要增强局部黏膜的细胞免疫应答,且稍增强系统体液免疫应答,未增强黏膜的IgA应答。免疫血清有中和作用。     

Biology and mucosal immunity to myxozoans

Myxozoans are among the most abundant parasites in nature. Their life cycles involve two hosts: an invertebrate, usually an annelid, and a vertebrate, usually a fish. They affect fish species in their natural habitats but also constitute a menace for fish aquaculture. Using different strategies they are able to parasitize and cause damage in multiple organs, including mucosal tissues, which they use also as portals of entry. In fish, the main mucosal sites include the intestine, skin and gills. Recently the finding of a specific mucosal immunoglobulin in teleost (IgT), analogous to mammalian IgA, and the capacity of fish to develop a specific mucosal immune response against different pathogens, has highlighted the importance of studying immune responses at mucosal sites. In this review, we describe the major biological characteristics of myxozoan parasites and present the data available regarding immune responses for species that infect mucosal sites. As models for mucosal immunity we review the responses to Enteromyxum spp. and Ceratomyxa shasta, both of which parasitize the intestine. The immune response at the skin and gills is also described, as these mucosal tissues are used by myxozoans as attaching surfaces and portal of entry, and some species also parasitize these sites. Finally, the development of immunoprophylactic strategies is discussed.     

Mucosal vaccines: a paradigm shift in the development of mucosal adjuvants and delivery vehicles

Mucosal immune responses are the first‐line defensive mechanisms against a variety of infections. Therefore, immunizations of mucosal surfaces from which majority of infectious agents make their entry, helps to protect the body against infections. Hence, vaccinization of mucosal surfaces by using mucosal vaccines provides the basis for generating protective immunity both in the mucosal and systemic immune compartments. Mucosal vaccines offer several advantages over parenteral immunization. For example, (i) ease of administration; (ii) non‐invasiveness; (iii) high‐patient compliance; and (iv) suitability for mass vaccination. Despite these benefits, to date, only very few mucosal vaccines have been developed using whole microorganisms and approved for use in humans. This is due to various challenges associated with the development of an effective mucosal vaccine that can work against a variety of infections, and various problems concerned with the safe delivery of developed vaccine. For instance, protein antigen alone is not just sufficient enough for the optimal delivery of antigen(s) mucosally. Hence, efforts have been made to develop better prophylactic and therapeutic vaccines for improved mucosal Th1 and Th2 immune responses using an efficient and safe immunostimulatory molecule and novel delivery carriers. Therefore, in this review, we have made an attempt to cover the recent advancements in the development of adjuvants and delivery carriers for safe and effective mucosal vaccine production.     

Modulation of mucosal immunity in a murine model of food-induced intestinal inflammation

Background Hypersensitivity or uncontrolled responses against dietary antigens can lead to inflammatory disorders like food allergy and current models reflect a variety of causes but do not reveal the detailed modulation of gut immunity in response to food antigens after breakdown in mucosal tolerance. Objective To develop and characterize a murine model for food‐induced intestinal inflammation and to demonstrate the modulation of gut immune response by dietary allergenic antigens. Methods C57BL/6 mice were sensitized with peanut proteins, challenged with peanut seeds and their sera and gut segments were collected for subsequent analyses. Results Sensitization and challenged with peanut seeds led to alterations in gut architecture with inflammatory response characterized by oedema in lamina propria and cell infiltrate composed mainly by eosinophils, mast cells, phagocytes, natural killer and plasma cells, together with low percentage of γδ⁺ and CD4⁺CD25⁺Foxp3⁺ cells in Peyer's patches. These animals also presented high levels of specific IgE and IgG1 in sera and modulation of mucosal immunity was mediated by increased expression of GATA‐3, IL‐4, IL‐13 and TNF‐α in contrast to low IFN‐γ in the gut. Conclusion A murine model for food‐induced intestinal inflammation was characterized in which modulation of gut immunity occurs by peanut antigens in consequence of T‐helper type 2 (Th2) allergic response and failure of regulatory mechanisms necessary for mucosa homeostasis, resembling food allergy. This work shed some light on the understanding of the pathogenesis of gastrointestinal disorders and intolerance in the gut and supports the development of therapies for food‐related enteropathies like food allergy, focusing on gut‐specific immune response.     

慢性粘膜免疫应答诱导的小鼠自身免疫综合征

空弯菌(CJ-S131)慢性感染小鼠具有SLE样自身免疫综合征。本文进一步用甲醛化空弯菌(CJ-S131菌苗)经口免疫BALB/c小鼠,每周两次,持续14周.模拟慢性感染时的慢性肠道粘膜免疫应答.发现免疫小鼠也具有SLE样自身免疫综合征,且较该菌慢性感染小鼠更显著。主要表现有:(1)全身免疫系统的淋巴组织显著增生;(2)B淋巴细胞多克隆激活;(3)多种自身抗体(包括抗ds-DNA.ss-DNA和组蛋白抗体)显著升高;(4)免疫复合物性肾小球肾炎;(5)多器官性(如肝、肠等组织)慢性炎症;(6)血管炎和血管周围炎。在体外自身免疫应答诱导实验中,免疫小鼠的脾细胞培养上清中,免疫球蛋白(总Ig)和抗DNA抗体显著高于非免疫小鼠。上述结果证实.空肠弯菌慢性感染所致的自身免疫综合征.和该菌抗原诱导的慢性肠道粘膜免疫应答有关。本实验为研究感染和自身免疫的关系提供了实用的动物模型。     

Effect of long-term continuous consumption of fermented milk containing probiotic bacteria on mucosal immunity and the activity of peritoneal macrophages

The effect of the long-term administration of commercial fermented milk containing probiotic bacteria in the mucosal immune response and peritoneal macrophages was analyzed. BALB/c mice were fed with fermented milk for 98 consecutive days. Small and large intestines were removed for histology; IgA, CD4, CD8 cells and cytokines-producing cells were counted. The influence on the immune cells associated with bronchus and mammary glands as well as on peritoneal macrophages was also analyzed. Continuous oral administration of fermented milk increased IgA+ cells in both parts of the intestine (small and large intestine). IL-10, a regulatory cytokine, increased in the intestinal cells in most samples. TNFalpha, IFNgamma and IL-2 producing cells were also enhanced. Values for CD4 and CD8(+) cell populations in lamina propria of the intestine were increased in relation to the control throughout the assay. No modifications in the histology of intestines were observed. Long-term consumption of fermented milk enhanced intestinal mucosa immunity, mediated by IgA+ cells and by cytokine production. This improvement of gut immunity was maintained and down-regulated by cytokines such as IL-10, preventing gut inflammatory immune response. The effect of this fermented milk on mucosal sites distant to the gut, such as bronchus and mammary glands, showed that in both tissues the increase in IgA+ cells was only observed at the beginning of the continuous consumption and no modifications in the number of cytokine positive cells were found. Similar observations were found when phagocytic activity of peritoneal macrophages was measured. It was demonstrated that the most evident effect of long-term consumption of fermented milk was observed in the intestine. Immunodulatory effects and the maintenance of intestinal homeostasis without secondary effects after long-term administration of fermented milk were also observed.     

Rabbit model for mucosal immunity in the bowel: I. Establishment of virus-infected ileal loops

An animal model was designed for use in studies of initial cellular immune responses to virus infection of the intestinal mucosa. The animal chosen was the New Zealand White rabbit and the mucosal site the subterminal ileum, isolated in a Thirty-Vella loop. The antigen used was parainfluenzavirus type 3, which would normally be destroyed by bile salts if ingested. Loops approximately 20 cm in length, each containing at least one Peyer's patch, were exteriorised through left paramedian stomata. Atrophic changes began to appear in the loops by 7 days, but no observable diminution in their associated lymphoid tissues was evident. The genesis of parainfluenzavirus type 3 infection in the loops was monitored by assay of sequential loop washings for infectious virus and in fluorescent antibody studies of cells from infected loop epithelia. Infectious virus was recovered for up to 13 days after inoculation and specific intracytoplasmic immunofluorescence was detected in loop epithelial cells. There was little serological evidence of systemic spread of the virus. A localised cellular immune response against parainfluenzavirus type 3 was mounted in the lymphoid tissues associated with the infected loops by day 14, but was not detected in systemic lymphoid tissues. No reactivity was detected in rabbits given inactivated virus via their loops or in those receiving infectious virus intravenously. This model appears to be capable of generating mucosal cellular responses to infection and may therefore be suitable for further studies in this field.     

白色念珠菌感染免疫应答的研究进展

白色念珠菌的致病是其与机体免疫系统相互作用的结果.研究发现,白色念珠菌感染人体时,刺激机体产生固有免疫及特异性细胞免疫和体液免疫应答.其中特异性细胞免疫占主导地位.了解认识白色念珠菌感染的免疫应答对诊断、预防及治疗白色念珠菌感染具有重要意义.     

An investigation of the ability of orally primed and tolerised T cells to help B cells upon mucosal challenge

The oral delivery of soluble antigens induces unresponsiveness to systemic challenge that can be demonstrated as a reduced ability of tolerised T cells to support B-cell expansion and antibody production. However, it remains controversial whether previously induced oral tolerance results in suppression or priming, or has no effect on B-cell responses upon oral challenge. Using a double adoptive transfer system, we primed or tolerised T cells (independently of B cells) with a high dose of fed antigen, and examined the ability of these primed or tolerised T cells to support B-cell clonal expansion in response to orally delivered conjugated antigen. We demonstrated directly in vivo that, in contrast to orally primed T cells, transgenic T cells tolerised by feeding a high dose of antigen are incapable of providing cognate help to support B-cell clonal expansion and antibody production in response to oral challenge. This defect appears to be a result of a reduced ability of orally tolerised transgenic T cells to clonally expand and migrate to B-cell follicles after oral challenge.     

黏膜免疫佐剂的研究进展

黏膜免疫系统是机体抵抗外来病原体入侵的第一道防线,弱毒苗通过黏膜免疫后可引起局部和全身性的免疫应答。由于疫苗经过消化道时常受到消化液的降解,在应用中不得不增加抗原的用量。因此为了提高机体对抗原的黏膜免疫力和系统免疫反应,不同类型黏膜免疫佐剂已悄然进入黏膜免疫的研究中。本文就近几年来国内外黏膜免疫佐剂的研究情况作一综述。     

黏膜免疫途径的研究进展

黏膜免疫系统是机体抵御病原体入侵的首道屏障,它包括消化道、呼吸道和生殖道黏膜等.通过不同的免疫途径进行局部免疫,对系统免疫和黏膜免疫系统的各部位产生的效果不同.提高机体的免疫力必须选择最佳的免疫途径.本文仅就近年来黏膜免疫的途径及效果的研究进展作一简要综述.