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1.
Current approaches to the prevention of severe rotavirus diarrhea and deaths in children have all been through the use of live oral vaccines. To develop a safe and effective inactivated rotavirus vaccine (IRV), a new simple, rapid and robust method for the inactivation is critical and essential because chemical inactivation commonly used for a number of killed vaccines has been a challenge and problematic for rotavirus. We have examined an array of thermal conditions and demonstrated that purified YK-1 rotavirus in diluent buffer can be completely inactivated by heat treatment, as evidenced by the lack of virus growth in two successive passages in cell culture. Unlike chemical treatment that often causes physical and biochemical damages to viruses, thermally inactivated rotavirus particles maintained their structural, biochemical and antigenic integrity. A two-dose intramuscular administration of thermally inactivated YK-1 rotavirus without adjuvant resulted in high titers of total and neutralizing antibody in serum of mice. Adjuvant Al(OH)(3) further led to enhanced antibody titers and also dramatically lowered the amount of antigens in the vaccine formulation. Our results demonstrate the potential of heat inactivation as a novel approach to the manufacture of a safe and efficacious parenteral rotavirus vaccine, which should serve as an important addition to and back up for live oral rotavirus vaccine in children.  相似文献   

2.
Zhang B  Yi S  Ma Y  Zhang G  Zhang Y  Xie T  Li H  Sun M 《Human vaccines》2011,7(2):248-257
Inactivated rotavirus vaccine is a safe and effective potential vaccine for the prevention of rotavirus infection among children, but no approved licensed vaccine is available now. In this study, a scalable inactivated rotavirus vaccine, prepared in Vero cells cultured by microcarrier fermentation, inactivated by formalin and absorbed by Al(OH)(3) adjuvant, was vaccinated into the six weeks-old female Balb/c mice by intramuscular injection. After twice immunization at interval of three weeks, both humoral and cell-mediated immune responses were assessed by ELISA, microneutralization assay and EISPOT assay. The results indicated that the scalable inactivated rotavirus vaccines induced not only high serum IgG antibody and neutralizing antibody responses, but Th1 and Th2 cytokine-secreting cell responses in mice immunized by the inactivated rotavirus vaccines. These results suggest that the scalable inactivated rotavirus vaccine has good immunogenicity, which provided the base for the scaled development of inactivated rotavirus vaccine in the future.  相似文献   

3.
Pentavalent botulinum toxoid adsorbed (ABCDE) vaccine is intended to protect military personnel from battlefield exposures to botulinum serotypes A-E. To determine the neutralizing antibody levels in serum that are indicative of protection against aerosolized botulinum toxins, a guinea pig model of passive antibody transfer was developed. Botulinum immune globulin (BIG), derived from plasma of vaccinated volunteers, was administered to guinea pigs by intraperitoneal injection to attain neutralizing antibody levels in serum of ca. 0.25 U ml(-1). Control groups were treated with vaccinia immune globulin (VIG), with dosages normalized to antibody content. Neutralizing antibody levels were determined by a mouse bioassay. Twenty-four hours after BIG treatment, animals were challenged with lethal levels (target of 25 x LCt(50)) of botulinum toxins by an inhalation route. Protection was defined as 80% or greater survival for BIG-treated animals. If protective, additional groups were treated with progressively smaller BIG dosages (75% decreases per iteration) and challenged with 25 x LCt(50) until protection was no longer afforded. Greater than 80% survival was observed at target levels of 0.25 U ml(-1) for all five serotypes. Breakthrough mortality (>20%) was observed at test levels of 0.05, 0. 004, 0.015, 0.014 and 0.003 U ml(-1) for serotypes A-E, respectively. These results, along with neutralizing antibody measurements from clinical trials, can be used to predict human efficacy following vaccination with pentavalent botulinum toxoid adsorbed (ABCDE) vaccine.  相似文献   

4.
Background: Immune protection against cholera infection is probably mediated in part by locally produced, intestinal secretory IgA (sIgA) antibodies. We study the kinetics of intestinal (sIgA) and systemic (serum IgG) antitoxin antibody responses after immunization with whole-cell/recombinant B subunit oral cholera vaccine (WC/rBS) in U.S. travelers to Mexico and Mexican volunteers.
Methods: Two doses of WC/rBS were administered 10 days apart to ten U.S. adults, newly arrived in Mexico, and 18 Mexican nationals. Serum IgG and intestinal secretory IgA (sIgA) antibodies to the B subunit of cholera toxin were measured from day 0 to day 21 by a direct enzyme-linked immunosorbent assay (ELISA).
Results: Positive serum IgG responses to vaccination were detected in 80% of U.S. adults and in 59% of Mexican adults. All volunteers, regardless of nationality, developed a positive sIgA antibody response to WC/rBS. No differences were observed between U.S. and Mexican volunteers in the magnitude and kinetics of serum IgG responses. We recorded differences in the kinetics of sIgA antibody, with early and late peak sIgA antitoxin responses demonstrated in the Mexican and U.S. volunteer groups, respectively. Although the presence or absence of antitoxin sIgA antibodies prevaccination (sIgA titer > 1:4) did not interfere with the final postimmunization magnitude of the antibody responses (sIgA measurements days 14 and 21), the initial measurement curves showed differences (sIgA measurements days 0 and 3).
Conclusions: The WC/rBS vaccine stimulated antitoxin antibody formation both in serum and locally in the intestine. The presence or absence of specific sIgA antibodies prevaccination did not seem to interfere with the magnitude of the antibody responses postvaccination (days 14, 21). The measurement of sIgA responses in fecal extracts appears to provide a simple and sensitive method to assess the intestinal immune response to orally administered vaccines.  相似文献   

5.
rDEN2/4Delta30(ME) is an attenuated chimeric dengue virus in which the prM and E structural proteins of the DEN4 candidate vaccine rDEN4Delta30 have been replaced by those of the prototypic DEN2 NGC virus. rDEN2/4Delta30(ME) was evaluated at a dose of 1,000 PFU in 20 healthy dengue-na?ve adult volunteers. Eight volunteers received placebo. Volunteers were monitored closely for adverse events and serum was collected for determination of the level and duration of viremia and neutralizing antibody response. The vaccine was well tolerated by all volunteers. The most common adverse events observed were a transient asymptomatic rash and mild neutropenia. All vaccines seroconverted to DEN2 and maintained significant antibody titers throughout the six-month trial duration. Eleven vaccinees had vaccine virus recovered from the blood during the study. RNA derived from virus isolates obtained from viremic volunteers was sequenced for confirmation of retention of the Delta30 mutation in the 3' UTR. The Delta30 mutation remained unchanged in each isolate, confirming the stability of the Delta30 mutation. Further evaluation of this vaccine in a tetravalent formulation is warranted.  相似文献   

6.
Acute rotavirus gastroenteritis can be successfully managed with oral and intravenous rehydration solutions; however, it is still a major cause of childhood mortality and morbidity in developing countries and is responsible for significant morbidity and health-care costs in developed countries. Pentavalent human-bovine rotavirus vaccine (HBRV) is an oral vaccine containing five live attenuated human-bovine reassortant strains containing the human serotypes responsible for the majority of rotavirus cases worldwide. Approximately three-quarters of all acute rotavirus gastroenteritis cases and almost all cases of severe gastroenteritis were prevented by pentavalent HBRV in a phase III clinical trial. Pentavalent HBRV has a favorable safety profile, with fever, irritability, vomiting and diarrhea generally reported in similar proportions of infants who received either vaccine or placebo. Results from a large phase III study indicate that there was no excess risk of intussusception among those vaccinated compared with placebo recipients. This review summarizes the current data on the clinical efficacy and safety of HBRV in healthy infants.  相似文献   

7.
In 1999, Serum Institute of India indigenously developed an adsorbed human diploid cell rabies vaccine (Rabivax). During 2000-04, this new vaccine was subjected to a series of immunogenecity and safety studies. Initially, an experimental batch of Rabivax (adsorbed) was assessed on ten healthy adult volunteers and its response was comparable with that of Merieux inactivated rabies vaccine (MIRV, lyophilized) which was used as a control. Subsequently, Rabivax (adsorbed) was assessed on forty-five suspect rabid dog bite cases with MIRV as control. The vaccine was found to be equally safe and immunogenic as MIRV and showed better rabies virus neutralizing antibody (RVNA) response on day 90 than MIRV. A post-licensing study conducted on 150 cases of suspect rabid animal bites showed it to be safe and immunogenic. To assess its long-term sero-efficacy some of these subjects tested after one year of follow up showed that 84% of them had adequate RVNA titers. In addition, a routine post-marketing surveillance done on 1608 animal bite cases demonstrated that Rabivax (adsorbed) was safe and efficacious. The adverse events to Rabivax (adsorbed) included pain at injection site (3.4%), swelling with induration (2.8%), fever and headache (1.4%). No serious adverse event was reported from the studies. In conclusion, Rabivax (adsorbed) is an immunogenic, safe and efficacious vaccine for rabies prophylaxis in humans.  相似文献   

8.
Sixteen dose formulations of our live-attenuated tetravalent dengue virus vaccines (TDV) were previously evaluated for safety and immunogenicity. Two of the sixteen candidate TDV formulations (Formulations 13 and 14) were selected for further evaluation. A new TDV formulation, Formulation 17, using a higher primary dog kidney (PDK) cell passage Dengue-1 virus (DENV-1) and a lower PDK cell passage DENV-4, was developed to optimize the neutralizing antibody response. All three formulations consist of combinations of 10exp3-5 pfu/dose of the four dengue vaccine virus serotypes. This double-blind, randomized trial in 71 healthy adult subjects evaluated vaccine safety, reactogenicity and immunogenicity. TDV's were given subcutaneously in the deltoid on Day 0 and 180 (6 months). Subjects were seen in clinic on Study Days 0, 10, 28, 180, 190 and 208 and filled out daily symptom diaries for 21 days after each vaccination. Formulation 13 was the most reactogenic, while both Formulations 14 and 17 were similar in reported reactions. Seventy-five percent, 31% and 31% of subjects were viremic on Day 10 after primary vaccination with Formulations 13, 14 and 17 respectively. Viremia was not detected in any subject following the second dose of vaccine. The immunogenicity endpoint was neutralizing antibody titer one month after the second vaccination. Thirty-six percent, 40% and 63% of vaccinated subjects developed tetravalent neutralizing antibodies after two doses of Formulations 13, 14 and 17, respectively. Formulation 17 was selected for further clinical evaluation based on this study.  相似文献   

9.
The trivalent inactivated NIVGRIP influenza vaccine was administered by nasal route to 26 young adults; a matched control group was represented by 19 subjects who received a placebo. Vaccination was followed by a higher proportion of rises in the level of neutralizing secretory antibodies (70-77%) than in that of serum HAI antibodies (19-42%) to the three influenza strains contained in the vaccine. Simultaneous rises in secretory antibody titers to three and two influenza antigens occurred in 50% and 23% of the vaccinees, respectively. The vaccine conferred a protection rate of 75%, as estimated by a 7-month clinical follow-up.  相似文献   

10.
Experimental infection of humans with A2 respiratory syncytial virus   总被引:1,自引:0,他引:1  
Development of a readily available challenge model of human respiratory syncytial virus (RSV) infection would be a useful tool for evaluation of antiviral agents and vaccine candidates. Accordingly, we evaluated a new challenge pool of RSV A2 virus, provided by the National Institutes of Allergy and Infectious Diseases. Healthy adults subjects were inoculated intranasally with various dilutions of the pool, and virus shedding, clinical symptoms, and immune response were studied. In a preliminary study of 36 randomly selected volunteers, stratified by serum neutralization titer both higher inoculum dose (4.7 log(10) TCID(50) virus) and lower antibody titer (<==10.36 log(2)), were associated with infection. In a second confirmatory study 12 of 13 (92%) subjects selected for low serum neutralizing activity shed virus after challenge with the high inoculum of virus. Mean peak virus shedding was 2.2 log(10) TCID(50)/mL nasal wash with a mean duration of 4 days. None of the subjects developed signs or symptoms of lower airway disease, although respiratory symptom scores and nasal mucus weight were temporally correlated with virus shedding. Prescreening for low levels of neutralizing antibody may allow selection of subjects with relatively higher susceptibility to experimental infections. This model provides a safe and efficient mechanism for proof-of-concept studies of anti-viral agents and RSV vaccines, as well as for investigation of immune responses to infection.  相似文献   

11.
目的  验证荧光灶试验(fluorescence focus assay,FFA)作为测定六价轮状病毒疫苗各型病毒滴度方法的可行性。方法  采用FFA法测定轮状病毒G1、G2、G3、G4、G8、G9型滴度,并验证该法的专属性、精密度、线性、准确性、范围和耐用性。 结果  各型病毒均可与对应的单克隆抗体(单抗)发生特异性荧光灶反应,不与抗异型病毒单抗发生交叉反应。试验内和试验间测定结果的相对标准偏差均小于5%。各型轮状病毒实测滴度与理论滴度间的线性相关系数均≥0.99。不同稀释度各型病毒的回收率为90%~120%。改变病毒培养时间对检测结果没有影响。该法的定量限为:G1、G2、G3、G4、G8、G9型滴度分别>2.8、>4.2 、>3.7、>3.6、>4.1和>4.2 lg荧光灶单位/ml,均符合六价轮状病毒疫苗的质控要求。结论  该法测定不同型轮状病毒滴度具有较好的专属性、精密度、线性和准确性,可用于六价轮状病毒疫苗各型病毒滴度的测定。  相似文献   

12.
BACKGROUND: The purpose of this study was to evaluate the tolerance and immunogenicity of a hepatitis A vaccine using immunopotentiating reconstituted influenza virosomes (IRIV) as adjuvant when administered simultaneously with a yellow fever vaccine (YFV). METHOD: An open prospective trial with two parallel groups was conducted with 105 volunteers to study the effect of these vaccinations on the anti-hepatitis A virus (HAV) antibody response. Half of the volunteers (53) received one dose of IRIV-HAV vaccine (Epaxal) and one dose of live attenuated YFV (Stamaril) on the same day at two different sites. Fifty-six volunteers were given a single injection of IRIV-HAV as a control group. Anti-HAV titers were measured at days 14, 28, months 3, 12, 13, and 24 using a standardized test (Enzymun test Anti-HAV). Neutralizing yellow fever antibodies were measured at days 14 and 28 for the YFV recipients. Regarding vaccine tolerance, the volunteers were asked to record all their adverse reactions on a standard report sheet for the 6 days following the immunization. RESULTS: Seroconversion rates for HAV were 88% after 14 days and 100% after 4 weeks. There was no statistically significant difference between the two groups every time the titers were checked (IRIV-HAV vs HAV only: D14: 81 vs 101; D28: 275 vs 368; M3: 153 vs 169; M12: 117 vs 226; geometrical mean titers (GMT) in mIU/mL). However, lower titers were found among male volunteers, and were not attributable to YFV administration. The seroconversion rates for YFV were 90% after 14 days and 96% after 4 weeks. No serious general side-effects and only mild local reactions were reported. The administration of a booster of IRIV-HAV at 12 months resulted in a 24-fold increase in GMT. CONCLUSION: When needed, the simultaneous administration of the IRIV-HAV and YFV is immunogenic, safe and well-tolerated, as volunteers seroconverted to both antigens, with no cross-interference.  相似文献   

13.
A live attenuated human rotavirus vaccine   总被引:1,自引:0,他引:1  
Rotavirus infections are the leading cause of severe gastroenteritis in young children worldwide. This review provides a summary of the development of a live oral rotavirus vaccine, Rotarix (GlaxoSmithKline, Rixensart, Belgium) developed from a single protective G1P[8] human strain. To attenuate the wild-type virus, the original isolate, 89-12, was passaged multiple times in tissue culture. Large safety and efficacy trials that have included more than 100,000 children around the world have shown the vaccine is safe and not associated with intussusception. The vaccine is highly immunogenic and protective against disease caused by all the most common circulating human serotypes. Efficacy against severe rotavirus gastroenteritis and hospitalization has ranged from 85-100%. Rotarix is available in the European Union, most countries in Latin America, Australia, and numerous other countries around the world. The vaccine is administered as two oral doses with at least four weeks between doses. The first dose may be administered from the age of 6 weeks, and both doses should be completed by 24 weeks of age.  相似文献   

14.
目的应用空斑减少中和试验对非典型肺炎灭活疫苗动物免疫血清进行中和抗体测定,以评价其免疫效果。方法用Vero-E6细胞接种6孔塑料细胞培养板,加两层含琼脂糖培养基,以中性红为染色剂建立空斑试验,以能减少50%的空斑为标准测定抗SARS中和抗体。结果三批非典型肺炎灭活疫苗免疫小鼠和家兔均产生较高的中和抗体。结论非典型肺炎灭活疫苗对两种动物具有良好的免疫效果。  相似文献   

15.
目的 观察乙型脑炎(乙脑)减毒活疫苗的接种反应和免疫原性.方法 分别选择52名(8月龄~50岁)和607名(8月龄~12岁)健康志愿者进行Ⅰ和Ⅲ期临床试验.试验组每人接种1次由上海生物制品研究所有限责任公司研制的乙脑减毒活疫苗(0.5 ml),对照组接种同样剂量的已上市乙脑减毒活疫苗.两组接种后的不良反应率和中和抗体阳转率用x2检验进行比较,中和抗体几何平均滴度用t检验进行比较.结果 试验组接种后有5.91%的人体温升高,对照组为7.96%,两组的体温反应发生率差异无统计学意义(x^2 =0.917,P=0.338).试验组Ⅰ期试验局部反应率为1.92%,Ⅲ期试验为0.25%,对照组Ⅲ期试验局部反应率为0.50%,两组的局部反应率差异无统计学意义(确切概率法,P=0.553).Ⅲ期免疫原性试验中,试验组的血清中和抗体阳转率为89.00%,抗体几何平均滴度为29.69;而对照组分别为74.59%和19.25,差异均有统计学意义(x^2=11.708,P=0.001;t=4.281,P=0.001).结论 本研究的试验性乙脑减毒活疫苗接种反应轻微,并具有良好的免疫原性.  相似文献   

16.
This study describes the isolation, purification, characterization, and adjuvant activity of an orally active adjuvant substance from the tuber of Pinellia ternata, as an active herbal component of the traditional Japanese herbal (Kampo) medicine, Sho-seiryu-to (SST, Chinese name: Xiao-Qing-Long-Tang), which has been reported to show oral adjuvant activity for nasally administered influenza HA vaccine [Int. J. Immunopharmacol. 16 (1994) 605]. The active compound was identified as 9S, 12S, 13S-trihydroxy-10E-octadecenoic acid using infrared spectra, proton magnetic resonance, mass spectrometry, and circular dichroism, and named pinellic acid. Oral administration of pinellic acid (1 microg) to BALB/c mice given primary and secondary intranasal inoculations of influenza HA vaccine (1 microg) enhanced antiviral IgA antibody (Ab) titers 5.2- and 2.5-fold in nasal and bronchoalveolar washes, respectively, and antiviral IgG Ab titers 3-fold in bronchoalveolar wash and serum. Intranasal administration of pinellic acid (1 microg) with influenza HA vaccine (1 microg) slightly enhanced antiviral IgG Ab titers in bronchoalveolar wash and serum but not antiviral IgA Ab titers in nasal and bronchoalveolar washes. Pinellic acid showed no hemolytic activity. The results of this study suggest that pinellic acid may provide a safe and potent oral adjuvant for nasal influenza HA vaccine.  相似文献   

17.
目的:对建立的抗H7N9流感病毒中和抗体快速检测方法进行方法学验证及初步应用。方法:分别采用不同代次细胞对高、中、低不同滴度的阳性血清进行多次平行检测,考察细胞代次对检验结果的影响;采用NIBSC提供的参考品对方法学的特异性进行验证;同时应用抗H7N9的阳性血清检测进一步评估方法的准确性和精密性;采用ELISA-MNT法和血凝抑制(hemagglutination inhibition,HI)试验分别接种H7N9灭活流感疫苗免疫的小鼠血清样本20份,分析两种方法检测结果的相关性。结果:采用ELISA-MNT中和法,使用不同代次MDCK细胞(25、30和35代)检测相同的血清样本的中和抗体滴度结果相同;该方法只对羊抗H7N9的血清具有较高保护力,对其他血清基本没有交叉反应;该方法准确性良好;该方法组间、组内精密性的平均变异系数分别为4%和11%。该方法测定H7N9型流感疫苗免疫后的小鼠血清抗体效价,其结果与HI抗体的相关系数为0.61,表明两种方法的检测结果之间呈良好的正相关性。结论:建立的微量病毒中和法能够满足H7N9流感病毒中和抗体效价检测的要求,可用于H7N9新型大流行流感疫苗的免疫评价。  相似文献   

18.
The immunogenicity and safety of the 10-valent pneumococcal conjugate vaccine, PHiD-CV, have been documented in European and Asian studies. In this open study conducted in Mexico (NCT00489554), 230 healthy infants received three doses of PHiD-CV and DTPa-HBV-IPV/Hib vaccines at 2, 4 and 6 months of age and two doses of oral human rotavirus vaccine at 2 and 4 months. Serotype-specific pneumococcal responses and opsonophagocytic activity (OPA) were measured one month post-dose 3. PHiD-CV's primary vaccination course was highly immunogenic against each of the 10 pneumococcal vaccine serotypes and carrier protein D. Antibody responses against pneumococcal serotypes and protein D were generally higher in Mexican infants compared with European antibody responses, and functional OPA responses were also higher or in the same range. The most frequent solicited local symptom was pain, with high but similar incidences of grade 3 pain reported at both injection sites (up to 15% of all doses). PHiD-CV was well tolerated, with no serious adverse events considered as causally related to vaccination. Most solicited symptoms were mild and there was no increase in incidence of solicited symptoms with successive vaccine doses.  相似文献   

19.
Protective immunity against anthrax is inferred from measurement of vaccine antigen-specific neutralizing antibody titers in serum samples. In animal models, in vivo challenges with toxin and/or spores can also be performed. However, neither of these approaches considers toxin-induced damage to specific organ systems. It is therefore important to determine to what extent anthrax vaccines and existing or candidate adjuvants can provide organ-specific protection against intoxication. We therefore compared the ability of Alum, CpG DNA and the CD1d ligand α-galactosylceramide (αGC) to enhance protective antigen-specific antibody titers, to protect mice against challenge with lethal toxin, and to block cardiotoxicity and hepatotoxicity. By measurement of serum cardiac Troponin I (cTnI), and hepatic alanine aminotransferase (ALT), and aspartate aminotransferase (AST), it was apparent that neither vaccine modality prevented hepatic intoxication, despite high Ab titers and ultimate survival of the subject. In contrast, cardiotoxicity was greatly diminished by prior immunization. This shows that a vaccine that confers survival following toxin exposure may still have an associated morbidity. We propose that organ-specific intoxication should be monitored routinely during research into new vaccine modalities.  相似文献   

20.
Stable vaccines administered to the lungs by inhalation could circumvent many of the problems associated with current immunizations against respiratory infections. We earlier provided proof of concept in mice that pulmonary delivered whole inactivated virus (WIV) influenza vaccine formulated as a stable dry powder effectively elicits influenza-specific antibodies in lung and serum. Yet, mucosal IgA, considered particularly important for protection at the site of virus entry, was poorly induced. Here we investigate the suitability of various Toll-like receptor (TLR) ligands and the saponin-derived compound GPI-0100 to serve as adjuvant for influenza vaccine administered to the lungs as dry powder. The TLR ligands palmitoyl-3-cysteine-serine-lysine-4 (Pam3CSK4), monophosphoryl lipid A (MPLA) and CpG oligodeoxynucleotides (CpG ODN) as well as GPI-0100 tolerated the process of spray freeze-drying well. While Pam3CSK4 had no effect on systemic antibody titers, all the other adjuvants significantly increased influenza-specific serum and lung IgG titers. Yet, only GPI-0100 also enhanced mucosal IgA titers. Moreover, only GPI-0100-adjuvanted WIV provided partial protection against heterologous virus challenge. Pulmonary immunization with GPI-0100-adjuvanted vaccine did not induce an overt inflammatory response since influx of neutrophils and production of inflammatory cytokines were moderate and transient and lung histology was normal. Our results indicate that a GPI-0100-adjuvanted dry powder influenza vaccine is a safe and effective alternative to current parenteral vaccines.  相似文献   

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