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1.
Various vaccines containing the 919 strain of ephemeral fever virus were evaluated in experimental calves and in commercial cattle. The vaccine virus was mixed with one of the adjuvants, Quil A (a saponin derivative), aluminium hydroxide gel, dextran sulphate or combinations of these. The response of experimental calves was evaluated by measuring the production of neutralising antibodies and by resistance to challenge with virulent virus; the response of commercial cattle was judged only by the production of neutralising antibody. Twelve calves given two doses of vaccine containing Quil A produced neutralising antibodies to bovine ephemeral fever virus and all were resistant to challenge with virulent virus given 28 to 76 days after the second vaccination. The vaccine given in three of these calves also contained aluminium hydroxide gel. Six of eight unvaccinated control calves succumbed to experimental challenge. In commercial cattle (17 to 26 animals per group) the serological response after two doses of vaccine containing Quil A or Quil A and dextran sulphate was significantly better than that after vaccines containing only dextran sulphate or after vaccines containing combinations of aluminium hydroxide gel and Quil A. The adjuvant Quil A alone was tested in cattle and shown to produce a transient soft swelling at the injection site as well as a rise in rectal temperature of greater than 1 degree C one day after inoculation. At least 99.99 per cent of viral infectivity was destroyed when the vaccine was mixed with Quil A, suggesting that live virus may not be essential in the immunogenicity of the vaccine. This vaccine overcame two of the problems associated with previous attenuated vaccines tested in Australia; the necessity for adjuvant and virus to be mixed immediately before use and the large volume of the vaccine.  相似文献   

2.
OBJECTIVE: To determine efficacy of vaccines incorporating QuilA, alum, dextran combined with mineral oil, or Freund adjuvant for immunization of feedlot cattle against Streptococcus bovis and Lactobacillus spp. ANIMALS: 24 steers housed under feedlot conditions. PROCEDURE: Steers were randomly assigned to 4 experimental groups and a control group. Animals in experimental groups were inoculated on days 0 and 26 with vaccines containing Freund adjuvant (FCA), QuilA, dextran combined with mineral oil (Dex), or alum as adjuvant. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were measured, along with fecal pH, ruminal fluid pH, and number of S bovis and Lactobacillus spp in ruminal fluid. RESULTS: Throughout the study, serum anti-S bovis and anti-Lactobacillus IgG concentrations for animals in the Dex, QuilA, and alum groups were similar to or significantly higher than concentrations for animals in the FCA group. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were significantly increased on days 26 through 75 in all 4 experimental groups, and there was a linear relationship between anti-S bovis and anti-Lactobacillus IgG concentrations. For animals in the QuilA and Dex groups, mean pH of feces throughout the period of experiment were significantly higher and numbers of S bovis and Lactobacillus spp in ruminal fluid on day 47 were significantly lower than values for control cattle. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that immunization of feedlot steers against S bovis and Lactobacillus spp with vaccines incorporating Freund adjuvant, QuilA, dextran, or alum as an adjuvant effectively induced high, long-lasting serum anti-S bovis and anti-Lactobacillus IgG concentrations. Of the adjuvants tested, dextran may be the most effective.  相似文献   

3.
The saponin adjuvant Quil A has been investigated in the vaccination of cattle against foot-and-mouth disease. Using a Frenkel type vaccine a dose-response relationship has been established between Quil A and neutralizing antibody titres. Ten ml of vaccine was combined with 0, 50, 200, 800, and 3200 µg of Quil A. The combinations were each injected into 4 animals. The local reaction on the site of injection produced by injection of the vaccine alone and in combination with different doses of Quil A has been estimated. On this basis a therapeutical dose at 1 mg of Quil A has been estimated to combine maximum adjuvant effect with a minimum of adverse reactions. This dose has been tested in the vaccination of cattle with FMD vaccines derived from BHK suspension cell virus of type O and A respectively. The vaccines were tested in 10 ml and 5 ml doses with or without Quil A, and each in 4 animals. It is concluded that Quil A is a valuable adjuvant for use in the induction of neutralizing antibodies against foot-and-mouth disease in cattle.  相似文献   

4.
Glutathione S-transferase in Fasciola gigantica (FgGST) was isolated by affinity chromatography, by which highly purified enzyme was obtained. FgGST on the SDS-PAGE showed three protein bands ranging 24.5-26.5kDa. Glutathione S-transferase (GST) activity was determined by HABIG method. FgGST was evaluated as vaccine alone or in combination with either aluminum hydroxide or saponin in sheep against F. gigantica infection. ELISA was used for detection of anti-FgGST IgG. After vaccination, all sheep were challenged with 120 metacercaria of F. gigantica. The results indicated that anti-GST IgG was not elevated after challenge. All sheep were slaughtered 24-26 weeks after challenge. The results indicated that, although after second vaccination, antibody titers rose markedly in GST-Al(OH)(3) and GST-saponin groups, but declined 4 weeks after challenge. No correlation between anti-GST IgG titers and protection was observed. The highest fluke burden reduction was observed in the group vaccinated with GST-saponin (32%), but this reduction was not statistically significant in comparison with the control group.  相似文献   

5.
Fasciola hepatica causes significant morbidity and mortality in dairy cattle in the Andean region of Cajamarca, Peru, where prevalence of infection of up to 78% has been reported. ELISA and Western blot analyses were used to characterise antibody responses in dairy cattle to adult F. hepatica to excretory-secretory (E/S), somatic (SO) and surface (SU) antigens. Three groups of dairy cattle - calves, heifers and adult cows - naturally exposed to F. hepatica in this region, were monitored every 2 months over a 2-year period. Calves, heifers and adult cows all had antibodies which recognised a 28kDa protein in the SO preparation, whereas only adult cows had antibodies that recognised a 28kDa protein in E/S products. All three groups of cattle responded to a 60-66kDa group of proteins in E/S and SU preparations and a 17kDa antigen in SO products was recognised by antibodies from cows and heifers but not calves. The total antibody response to E/S antigens measured by ELISA, increased over time in calves and remained constantly high over the 2-year period in all three groups of cattle. Slight fluctuations in the antibody response occurred in the group of heifers and cows coinciding with seasonal changes in the level of challenge.  相似文献   

6.
The saponin adjuvant Quil A was investigated in trivalent vaccination against foot-and-mouth disease with a concentrated vaccine based on BHK suspension cell virus of the serotypes O, A and G. The activity in cattle was estimated on the basis of seroneutra-lizing antibodies. Five and 10 ml doses with or without 1 mg of Quil A were each injected into 6 animals. Seroneutralizing antibodies were estimated at regular intervals during a period of 29 weeks. The activity in guinea pigs was estimated by experimental challenge. One ml doses of serial 4-fold dilutions of the vaccine with or without 50 µg of Quil A were injected into 24 groups of 20 guinea pigs. Challenge was given 3 weeks after vaccination.It was concluded that Quil A showed adjuvant activity in cattle and guinea pigs with all the serotypes used in the trivalent vaccination.  相似文献   

7.
Three groups of four heifers were vaccinated twice, 11 weeks apart. One group received a commercial pomona vaccine with aluminium hydroxide adjuvant, the second a similar experimental vaccine, and the third a Freund's compete adjuvant (FCA) vaccine. After 47 weeks, the heifers were challenged with at least 65 × 108 virulent serovar pomona organisms.

All vaccinated animals resisted the challenge, and leptospirae were only found in urine from unvaccinated controls.

The outcome of the challenge was not predictable from microscopic agglutination, cold and warm complement fixation, and growth inhibition titres.

The FCA vaccine gave rise to considerably higher antibody responses than the two aluminium hydroxide vaccines, which gave similar responses.  相似文献   

8.
Two strains of mice (NMRI and C57/BL) were each immunized with a 15kDa recombinant Fasciola hepatica fatty acid binding protein (FABP) (Fh15) and challenged percutaneously with Schistosoma bovis cercariae. C57/BL mice immunized with Fh15 had significant reductions in S. bovis worm burden recoveries (72% reductions over controls). When using NMRI mice, Fh15 in Freund's adjuvant failed to induce significant protection against S. bovis. In C57/BL mice, only antibodies to the IgG2a isotype increased after the second immunization and remained high through 8 weeks of S. bovis infection. This is the first time that a heterologous recombinant molecule from F. hepatica has been used in vaccination against S. bovis, obtaining a significant reduction in the number of worms in C57/BL mice.  相似文献   

9.
Chronic Fasciola hepatica infection is correlated with the development of a T helper (Th2)-predominant immune response. To determine whether immunostimulatory CpG-containing oligodeoxynucleotides (CpG-ODN) or Freund's complete adjuvant (FCA), known to promote a Th1 (T helper 1) immune responses, could provide protection from F. hepatica infection, total homogenate (TH) of F. hepatica mixed with CpG-ODN or FCA were injected subcutaneously (s.c.) into Wistar rats. A F. hepatica-specific Th1-predominant immune response was induced with CpG-ODN or FCA in lymph nodes of immunized animals. Lymph node cells from TH-CpG-ODN or TH-FCA immunized rats showed increased antigen-specific proliferation with high levels of INFgamma, compared to lymphocytes from rats injected with TH alone. In contrast, these two groups of immunized animals did not modify IL-4 release by draining lymph node cells, when they were subsequently stimulated with TH in vitro. However, a significant reduction in the burden of flukes (76.7%) was only observed in rats immunized with TH-FCA. Conversely, immunization of rats with TH-CpG-ODN did not promote protection against the parasite. Therefore, even though CpG-ODNs and FCA induced Th1 type responses, only FCA provided a significant protection to rats infected with F. hepatica.  相似文献   

10.
Immunogenicity of and protection afforded by Pasteurella haemolytica bacterins were studied in calves. Bacterins contained an aluminum hydroxide in gel (ALH) adjuvant or one of the following oil-in-water adjuvants: Freund's complete adjuvant (FCA), Freund's incomplete adjuvant (FIA), and trehalose dimycolate (TDM). On days 0 and 7, calves were vaccinated with phosphate-buffered saline solution (PBSS), a bacterin, or live P haemolytica. Transthoracic intrapulmonic challenge exposure was done on day 21. In 3 experiments, there were no significant (P greater than 0.05) differences between lung lesions induced in PBSS-or ALH bacterin-vaccinated calves. Both FCA and FIA bacterins significantly (P less than 0.05) enhanced resistance against challenge exposure. Resistance induced by FCA and FIA bacterins was comparable with that induced by vaccination with live P haemolytica. Calves vaccinated with FIA bacterin and challenge-exposed to P haemolytica at a concentration of 4.5 X 10(9) colony-forming units (4.5 times greater than used in the first 3 experiments) resisted challenge exposure similar to calves given live organisms. The TDM bacterin failed to enhance resistance. All bacterins caused a significant increase (P less than 0.05) in serum antibody to P haemolytica somatic antigens, as measured by a quantitative fluorometric immunoassay. Pasteurella haemolytica leukotoxin neutralizing antibody titers did not increase significantly (P greater than 0.05) in sera after vaccination with any bacterin. Vaccination with FCA and FIA bacterins resulted in a significant increase (P less than 0.001) in serum antibody to a carbohydrate-protein subunit of P haemolytica, as measured by an enzyme-linked immunosorbent assay.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
中药黄芪多糖的免疫佐剂作用   总被引:13,自引:3,他引:13  
分别将黄芪多糖提取物、白油-吐温、氢氧化铝作为佐剂制备金黄色葡萄球菌灭活苗混合免疫家兔和奶牛,观察家兔免疫前后血清抗体滴度变化以及攻毒后白细胞数目变化和淋巴细胞百分比变化。对奶牛免疫后测其血清抗体和乳汁中体细胞数变化,结果注射疫苗后乳汁中体细胞数都有所下降,黄芪多糖组较其它组下降较快,幅度较大。黄芪多糖和抗原混合物免疫动物后未见不良反应,且抗原免疫血清抗体比氢氧化铝和白油-吐温佐剂组的抗体滴度增加快,幅度显著增高且抗体维持一个较高水平,而攻毒后家兔白细胞数和淋巴细胞数也较氢氧化铝和白油-吐温佐剂组增加较多。因此黄芪多糖是一种有效的佐剂。  相似文献   

12.
Fourteen different adjuvants, given either in single or combined form with another compound were compared in guinea pigs for their ability to potentiate humoral immunity to porcine parvovirus (PPV) antigen after 2 vaccinations. Two injections were given, the second 3 weeks following the initial vaccination. Antibody concentrations to PPV in sera from injected animals were measured over a 5-week period by the hemagglutination inhibition test. At the conclusion of the experiment, guinea pigs injected with the following adjuvants and PPV antigen: CP-20 961 (Avridin), 50% aluminum hydroxide gel, ethylene maleic anhydride (EMA), oil and water emulsion (O/W) and dimethyl-dioctadecyl-ammonium bromide (DDA) immunologically responded with high geometric mean HI titers (380, 224 and 427, 602, 512, 1202 respectively), whereas guinea pigs receiving Emulsan, sodium dodecyl sulfate (SDS), L-121, combinations of Emulsan/aluminum hydroxide, SDS/aluminum hydroxide and B. pertussis/aluminum hydroxide responded with low mean titers (54, 64, 18, 27, 11, 64, 14, 20 respectively). Guinea pigs injected with antigen without adjuvant responded weakly with geometric mean titers of 3.3 and 16 for the 2 groups tested. Prior to booster injection, guinea pigs immunized with 13 of the preparations had low (less than 4) or undetectable antibody titers. Antibody titers from guinea pigs receiving DDA adjuvant continued to rise throughout the duration of the experiment and at the conclusion had the highest mean titers of the groups tested (1202). The 2 groups immunized with 50% aluminum hydroxide gel had high mean titers (224, 427), but in both instances there was a wide range of titers within a group evidenced by high standard deviations. In contrast, guinea pigs receiving either DDA, CP-20 961, O/W or EMA had antibody titers within a narrow range and small standard deviation. The significance of aluminum hydroxide gel concentration on immunogenicity is discussed.  相似文献   

13.
The dot-ELISA reaction was used to study the dynamics of IgG titers in cattle naturally infected with Fasciola hepatica after anthelmintic treatment and during reinfection. Excretion/secretion products (ES) of the parasite were used as antigens for the dot-ELISA. IgG antibodies were no longer detectable by dot-ELISA, 4-6 months after nine animals received the first of three weekly doses of triclabendazole (15 mg kg(-1)) and were then maintained on a pasture free of F. hepatica metacercariae. Six fluke-free cattle began shedding F. hepatica eggs 3-6 months after grazing a pasture contaminated with metacercariae of the parasite. A detectable increase in dot-ELISA IgG antibody levels was observed 2-4 weeks after natural reinfection by grazing a similar pasture contaminated with F. hepatica metacercariae. The usefulness of the dot-ELISA system to diagnose chronic infection by serology is complicated by previous treatment against the parasite. It is concluded that the ES antigens can be useful to detect early infection of cattle with F. hepatica in a dot-ELISA system  相似文献   

14.
Methods of contraception are necessary for management of zoo felids; however, the most commonly used contraceptive (melengestrol acetate implant) is associated with serious adverse reactions with long-term use. Porcine zona pellucida (pZP) vaccines are promising as contraceptives, but their safety in zoo felids has not been tested. pZP vaccine was administered to 27 female felids representing 10 species, including African lion (Panthera leo), Asian leopard (P. pardus), jaguar (P. onca), tiger (P. tigris), snow leopard (P. uncia), cougar (Felis concolor), Siberian lynx (F. lynx), Canada lynx (F. canadensis), serval (F. serval), and bobcat (F. rufus), in 15 facilities. Over 6 wk, each animal received three i.m. injections of 65 microg pZP with Freund's complete adjuvant (FCA), Freund's incomplete adjuvant, or carbopol as the adjuvant. Behavioral signs of estrus were seen in 14 of the vaccinated felids. An unacceptably high incidence of adverse reactions was seen including injection site swelling, lameness, limb swelling, or abscessation (or all) in five felids after injection with FCA as the initial adjuvant. Adverse behavioral signs, including increased irritability and aggression, were seen in four felids. Six of the felids were assayed for antibodies against pZP during the 12 mo after vaccination; all showed antibody production. Antibody levels appeared to peak 1-4 mo after vaccination began, although elevated antibody levels persisted in two animals for > 12 mo after the first injection. All vaccinated felids were ovariohysterectomized 3-13 mo after vaccination. Folliculogenesis was present in all treated animals, and there was no histopathologic evidence of inflammatory damage to ovaries. Contraceptive efficacy was not specifically evaluated in this study; however, two of the three felids housed with an intact male became pregnant during the study, one of which gave birth to healthy cubs.  相似文献   

15.
For evaluating the influence of the age of the vaccinated birds on the development of antibodies, five groups of turkey poults were inoculated subcutaneously at day 1, 7, 10, 14 and 21 of life with vaccine containing inactivated Bordetella avium and Freund's incomplete adjuvant. No matter which vaccine schedule was used, serum antibodies with the ELISA were first detected at the 28th day of life and increased continuously until the 49th day, when it exhibited either a peak or a plateau. Aluminium hydroxide, Freund's complete and incomplete adjuvant and a mineral oil-arlacel-tween-mixture being permitted adjuvants (appendix II EWG 2377/90) and the adjuvant Gerbu 100 were evaluated for their suitability. Turkeys were vaccinated at the age of three weeks and examined clinically as well as serologically up to the 11th week. Humoral antibodies were detected quantitatively using an ELISA for IgG and a microagglutination test for IgM and qualitatively using immunodiffusion. The damage at the application site was rated by measurement of the swelling of the tissue. In the 10th week, the animals were infected with the agent for challenge. The serological examination for IgG antibodies in the ELISA both treatments with Freund's adjuvants resulted in high titers, which differed significantly from the unvaccinated control after 21 days. IgM could be detected from day 7 onwards in all vaccinated groups and showed the highest titers when aluminium hydroxide was used as adjuvant. In the immunodiffusion assay, precipitating antibodies could be found from the first week after vaccination onwards. There was no correlation between the occurrence of precipitating antibodies and ELISA titers. The measurements of the swelling of the tissue in the beginning showed the largest swellings in the animals injected with Freund's incomplete adjuvant and differed significantly from the unvaccinated control. In the 10th week, the animals were infected with Bordetella avium for challenge. In comparison to the unvaccinated animals, all vaccinated turkeys, no matter which adjuvant was used, showed a distinct and significant reduction of the reisolation rate.  相似文献   

16.
The IgG2 anti-Brucella antibody response of cattle to Brucella vaccination and infection was measured. Three groups of animals were studied; Group 1 contained 11 non-vaccinated cows, Group 2, 17 cows vaccinated with a low dose of Strain 19 vaccine and Group 3, 17 cows vaccinated with a high dose of Strain 19 vaccine. All animals were challenged at Week 33 with an infectious isolate of B. abortus (Strain 2308). Studies of the IgG2 antibodies response indicated an absolute correlation between anti-Brucella IgG2 levels and infection of the animal. All animals showing reciprocal titers of greater than or equal to 3000 (16 of 45 tested) were found to be positive for the challenge organism at slaughter. Animals with reciprocal IgG2 titers less than or equal to 1000 (29 of 45 tested) were found to be negative for the challenge organism at the time of slaughter. The predictive value of IgG2 antibody levels for infection held for animals in all three groups and consequently this suggests that monitoring of specific IgG2 anti-Brucella antibody levels may be of value in detection of Brucella-infected cattle.  相似文献   

17.
人参皂甙Rb1的免疫佐剂作用   总被引:20,自引:0,他引:20  
分别将人参皂甙Rbl(人参主要成分之一)以及氢氧化铝胶作为佐荆和金黄色葡萄球菌菌体抗原混合免疫豚鼠,观察免疫前后血清抗体滴度变化;并用Rbl和奶牛乳房炎金黄色葡萄球菌疫苗混合免疫奶牛,观察免疫前后血清抗体滴度变化,以及血液淋巴细胞在刀豆蛋白A(ConA)、美洲商陆(PWM)和金黄色葡萄球菌抗原刺激下的体外细胞增殖反应。结果表明,Rbl和抗原混合物免疫动物后,未见任何不良反应;Rbl组豚鼠血清抗体滴度比对照组和氢氧化铝胶佐剂组滴度增加快,幅度显著增高;Rbl组奶牛血清抗体滴度比对照组奶牛显著增加,ConA、PWM和金黄色葡萄球菌抗原诱导的血液淋巴细胞体外细胞增殖反应比对照组显著提高。因此,Rbl是一种有效的免疫佐剂。  相似文献   

18.
Adult New Zealand rabbits were vaccinated at 2-week intervals with three doses of 100 micrograms of infective larval somatic proteins (L3SP) administered subcutaneously with Freund's complete adjuvant (FCA) or beryllium hydroxide and then challenged orally with 10,000 L3. Groups of rabbits immunized orally with three doses of 5000 or 2000 L3 served as vaccination controls. Intestinal worm burdens on Day 21 after challenge revealed that beryllium hydroxide effectively potentiates the protective immunogenicity of L3SP. The level of protection obtained using the beryllium adjuvant (94.8%) was nearly as high as that in rabbits immunized with three doses of 5000 L3 (99.8%). Rabbits vaccinated using FCA showed very poor immunity (29.5%). Local and systemic antibody levels detected by radioimmunoprecipitation tests using 125I-L3SP showed very little correlation with the degree of protection. The beryllium hydroxide-treated group demonstrated significantly higher bile IgA antibody levels than other experimental rabbits. FCA-treated rabbits developed a much higher serum precipitating antibody response, detectable using gel double diffusion tests, than the beryllium group. Also, mucosal IgA antibody levels detected on Day 21 after challenge were significantly higher in the FCA group than in other groups.  相似文献   

19.
Culture filtrate protein (CFP) vaccines have been shown to be effective in small animal models for protecting against tuberculosis while immunisation with these types of vaccines in cattle has been less successful. A study was conducted in cattle to evaluate the ability of selected adjuvants and immunomodulators to stimulate protective immune responses to tuberculosis in animals vaccinated with Mycobacterium bovis CFP. Seven groups of cattle (n=5) were vaccinated with M. bovis CFP formulated with either Emulsigen or Polygen adjuvant alone or in combination with a specific oligodeoxynucleotides (ODN), polyinosinic acid: polycytidylic acid (poly I:C) or poly I:C and recombinant granulocyte-macrophage colony stimulating factor. Two additional groups were vaccinated subcutaneously with BCG or non-vaccinated. In contrast to the strong interferon-gamma (IFN-gamma) responses induced by BCG, the CFP vaccines induced strong antibody responses but weak IFN-gamma responses. The addition of CpG ODN to CFP significantly enhanced cell-mediated responses and elevated antibody responses to mycobacterial antigens. Of the CFP vaccinated groups, the strongest IFN-gamma responses to CFP vaccines were measured in animals vaccinated with CFP/Emulsigen+CpG or CFP/Polygen+CpG. The animals in these two groups, together with those in the BCG and non-vaccinated groups were challenged intratracheally with virulent M. bovis at 13 weeks after the first vaccination and protection was assessed, by examination for presence of tuberculous lesions in the lungs and lymph nodes, 13 weeks later at postmortem. While BCG gave the best overall protection against tuberculosis, significant protection was also seen in animals vaccinated with CFP/Emulsigen+CpG. These results establish an important role for CpG ODN in stimulating protective Th1 responses to tuberculosis in cattle and indicate that a sub-unit protein vaccine can protect these animals against tuberculosis.  相似文献   

20.
The protective capacity of an adult stage Ostertagia ostertagi globin antigen was tested in four vaccination experiments in cattle. In a preliminary experiment, calves were vaccinated three times intraperitoneally with 250 microg globin in Freund's adjuvant and challenged with a trickled infection of 25,000 infective larvae. In three subsequent field studies, calves were vaccinated twice or three times intramuscularly with 80-100 microg globin in Quil A and challenged with a natural gastrointestinal nematode infection on pasture. Higher globin-specific antibody levels were detected in the vaccinated calves than in the control animals in all vaccine trials. In the preliminary experiment, geometric mean cumulative egg counts in the globin group were reduced by 52% and total worm burdens were reduced by 28%, compared to the controls. In the first field trial cumulative faecal egg counts were reduced by 63% in the vaccinated calves. However, the reduction in faecal egg output in these two experiments was not statistically significant and no reduction in faecal egg counts was observed in the vaccinated animals in the two last field trials. In conclusion, vaccination of calves with O. ostertagi globin resulted in highly variable protection levels after challenge infection.  相似文献   

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