ABSTRACT
This study was designed to evaluate the extent of the protection for bovine viral diarrhea virus type 2 (BVDV-2) infection, afforded by vaccination with a combo inactivated vaccine, which contains bovine viral diarrhea virus type 1 (BVDV-1) and infectious bovine rhinotracheitis virus (IBRV). Five 3-4-month-old calves were intramuscularly vaccinated with a single dose of the combo vaccine and boosted with same dose three weeks after the first vaccination, with five mock immunized calves serving as a control group. Twenty-one days after the second vaccination, all calves were challenged with BVDV-2 SX08 strain by spray into nostril. The unvaccinated animals developed typical clinical signs of high rectal temperature, diarrhoea with erosions and a dramatic drop in leukocyte counts. These signs occured markedly less in all vaccinated animals, the rectal temperature, leukopenia and virarmia of which, were significantly less than the mock immunized calves. It can be concluded that vaccination with the combo inactivated vaccine affords cross-protection against clinical effects of a challenge-infection with BVDV-2 SX08 strain, although it was part protection.(AU)
Este estudo foi desenvolvido para avaliar a extensão da proteção contra a infecção pelo vírus da diarréia viral bovina tipo 2 (BVDV-2) através da vacinação com uma vacina combinada inativada contendo o vírus da diarréia viral bovina tipo 1 (BVDV-1) e vírus da rinotraqueíte de bovinos infecciosos (IBRV). Cinco bezerros com 3 a 4 meses de idade foram vacinados via intramuscular com uma dose única da vacina combinada e reforçados com a mesma dose três semanas após a primeira vacinação, com cinco bezerros imunizados em simulação servindo como grupo controle. Vinte e um dias após a segunda vacinação, todos os bezerros foram desafiados com a cepa BVDV-2 SX08 por spray na narina. Os animais não vacinados desenvolveram sinais clínicos típicos, como alta temperatura retal, diarréia com erosões e queda drástica na contagem de leucócitos. Estes sinais tiveram ocorrência significativamente menor em todos os animais vacinados, cuja temperatura retal, leucopenia e virarmia eram significativamente menores do que os bezerros simulados. É possível concluir que a vacinação com a vacina combinada inativada proporciona proteção cruzada contra os efeitos clínicos de uma infecção provocada pela cepa BVDV-2 SX08, embora tenha sido parcialmente protegida.(AU)
Subject(s)
Animals , Cattle , Vaccination , Vaccines, Combined/analysis , Diarrhea Virus 1, Bovine Viral/immunology , Diarrhea Virus 2, Bovine Viral/immunology , Cross Protection , Vaccines, Inactivated , Leukocyte CountABSTRACT
Objective To evaluate the immunogenicity of the recombinant human papillomavirus type 68b (HPV68b) virus-like particles(VLPs)in a mouse model.Methods The L1 protein of HPV type 68b was successful expressed in the Hansenula polymorpha strain (NVSI-68b-1).Processes including purifi-cation and reconstitution were performed to achieve pure HPV 68b VLPs.The purity, morphology and immu-nogenicity of the purified HPV 68 b VLPs were further analyzed .The BALB/c mice were immunized with HPV68b VLPs formulated on aluminum adjuvant .Pseudovirus-neutralizing antibody ( PsV NAb) assay was performed to detect the neutralizing antibodies in serum samples .Results The HPV 68 b L1 VLPs were ob-tained as indicated by the results of SDS-PAGE, Western blot assay , HPLC, electron microscopy and dy-namic light scattering with a high purity of 95%.Transmission electron microscopy and dynamic light scat-tering analysis revealed that the HPV68b L1 VLPs resembled the native virus with an average particle diame-ter of 50 nm.High levels of HPV68b-neutralizing antibodies were detected in serum samples from the mice immunized with HPV68b L1 VLPs.Moreover, a cross-protective efficacy of HPV68b L1 VLPs for HPV68a was observed .Conclusion This study suggested that the recombinant HPV 68 b VLPs expressed in a Han-senula polymorpha strain might be used as a potential candidate for the development of HPV vaccine .
ABSTRACT
We investigated the existence of cross-protection between two anti-leptospirosis monovalent experimental bacterins produced with two strains of Leptospira serogroup Pomona: Fromm strain of serovar Kennewicky, isolated from pigs in the United States, and strain GR6 of serovar Pomona isolated from pigs in Brazil. Both were added of aluminum hydroxide as an adjuvant. Experimental bacterins were tested with the hamster potency test in order to assess protection provided against the disease and against the establishment of kidney infection. Controls were polyvalent commercial vaccine produced with Leptospira strains isolated outside Brazil, which included a representative of Pomona serovar, or Sorensen solution added of aluminum hydroxide adjuvant. The challenge was performed with cross-strains of serogroup Pomona tested in accordance with international standards established for the potency test. After 21 days of the challenge, survivors were killed to evaluate the condition of Leptospira renal carrier. Experimental bacterins protected hamsters against homologous and heterologous strains, demonstrating the existence of cross-protection. The commercial vaccine protected the hamsters challenged with both strains, but there was a high proportion of animals diagnosed as renal carriers when the challenge was performed with strain GR6, isolated from pigs in Brazil.
Subject(s)
Animals , Cricetinae , Bacterial Vaccines/administration & dosage , Bacterial Vaccines/immunology , Cross Protection , Leptospirosis/immunology , Leptospirosis/prevention & control , Adjuvants, Immunologic/administration & dosage , Aluminum Hydroxide/administration & dosage , Carrier State/microbiology , Carrier State/prevention & control , Kidney/microbiology , Leptospira/isolation & purification , Treatment OutcomeABSTRACT
Na atualidade, o sorovar Copenhageni é o representante do sorogrupo Icterohaemorrhagiae, mantido por roedores sinantrópicos, que tem prevalecido nos cães e seres humanos das grandes metrópoles brasileiras. A despeito de alguns autores sugerirem a existência de proteção cruzada entre sorovares incluídos em um mesmo sorogrupo esta condição ainda não foi suficientemente esclarecida para os sorovares Icterohaemorrhagiae e Copenhageni. No presente trabalho cães adultos com dois a seis anos de idade primo-vacinados com três doses intervaladas de 30 dias a partir dos 60 dias de idade e revacinados anualmente com vacina anti-leptospirose polivalente contendo os sorovares Canicola, Icterohaemorrhagiae, Grippotyphosa e Pomona foram revacinados com a mesma vacina e aos 30 dias da revacinação foram submetidos aos testes de soroaglutinação microscópica (SAM) e de inibição do crescimento de leptospiras in vitro (TICL), para avaliação comparativa dos níveis de anticorpos produzidos para os sorovares Canicola, Icterohaemorrhagiae e Copenhageni. Os resultados obtidos indicaram que a imunidade conferida pela vacina para o sorovar Icterohaemorrhagiae é mais duradoura que a observada para o sorovar Canicola, já que títulos de anticorpos neutralizantes >1,0 log10 foram observados antes do reforço vacinal não havendo substancial aumento após a revacinação. Quanto ao sorovar Canicola, a revacinação resultou em considerável aumento do título de anticorpos neutralizantes quando comparado ao momento anterior a revacinação (p=0,001). A análise dos valores encontrados após a revacinação demonstrou claramente que cães revacinados com bacterina produzida com o sorovar Icterohaermorrhagiae não apresentam aumento do título de anticorpos inibidores do crescimento contra o sorovar Copenhageni, em nível suficiente para inibir o crescimento de leptospiras. Apesar disso, os títulos de anticorpos inibidores de crescimento anti-Copenhageni encontrados antes e após a revacinação demonstraram que, pelo menos certo grau de proteção contra a infecção por esse sorovar pode ser esperado para os cães vacinados com bacterinas do sorovar Icterohaemorrhagiae, não sendo, no entanto, uma proteção cruzada completa.
Currently, the serovar Copenhageni is the representative of serogroup Icterohaemorrhagiae maintained in synanthropic rodents found most frequently in dogs and humans in metropolitan areas of Brazil. Despite some authors have suggested the existence of cross-protection between serovars included in the same serogroup, this condition has not yet been sufficiently clarified for serovars Icterohaemorrhagiae and Copenhageni. In the present work, 2 to 6-year-old dogs, vaccinated at 60, 90 and 120 days of age and thereafter, revaccinated annually with commercial vaccine containing Canicola, Icterohaemorrhagiae, Grippotyphosa and Pomona bacterins were evaluated as to the immune status against leptospirosis before and 30 days after revaccination. Mycroscopic agglutination test (MAT) and in vitro growth inhibition test (GIT) were performed to search for agglutinating anti-Leptospira antibodies and neutralizing anti-Leptospira antibodies, respectively for serovars Canicola and Icterohaemorrhagiae, and additionally, for serovar Copenhageni, not included in the vaccine. The results showed that the immunity conferred by the vaccine to serovar Icterohaemorrhagiae is more lasting than that observed for serovar Canicola, since neutralizing antibody titers >1.0 log10 were observed before the booster vaccination with no substantial increase after revaccination. As for the serovar Canicola, revaccination resulted in a considerable increase in neutralizing antibody titer when compared to the one observed previously to the revaccination (p=0.001). The analysis of the data obtained by GIT allowed us to conclude that dogs given vaccine containing Icterohaemorrhagiae bacterin did not produce neutralizing antibodies against serovar Copenhageni enough to inhibit leptopiral growth at the same level as occurred for the homologous serovar. Despite this, the GIT titer found for serovar Copenhageni before and after revaccination showed that at least, some level of protection could be expected for dogs vaccinated with serovar Icterohaemorrhagiae bacterin, not a complete cross protection.
Subject(s)
Animals , Dogs , Antibody Formation , Dogs , Leptospira interrogans serovar canicola/isolation & purification , Leptospira interrogans serovar icterohaemorrhagiae/isolation & purification , Leptospira interrogans serovar pomona , Vaccination/veterinaryABSTRACT
PURPOSE: The cross-protection of 7-valent pneumococcal conjugate vaccine (PCV7) against vaccine-related serotypes has been controversial. We investigated the serological properties of cross-protective antibodies against vaccine-related serotypes 6A, 6C, and 19A induced in young children aged 12-23 months after booster immunization of PCV7. METHODS: IgG and IgM antibody concentrations and opsonic index (OI) against vaccine serotypes 6B and 19F and vaccine-related serotypes 6A, 6C, and 19A were measured by ELISA and opsonophagocytic killing assay (OPA) in 4 selected immunesera. The serological properties and antigenic specificity of protective antibodies were determined by IgM depletion of immunesera, OPA, and competitive OPA against serogroup 6 and 19 pneumococci. RESULTS: Compared to pre-IgM depleted immunesera, OI of IgM-depleted immunesera against 6B and 19F decreased and OI against 6A, 6C, and 19A decreased, too. In competition OPA, free 6B and 19F polysaccharide completely inhibited the immune protection against vaccine-related serotypes 6A, 6C, and 19A as well as vaccine types 6B and 19F. CONCLUSIONS: The booster immunization of PCV7 certainly induced cross-protective antibodies against vaccine-related serotypes 6A, 6C, and 19A with both IgG and IgM isotypes. Furthermore, IgM antibodies are more highly contributed to opsonophagocytic activity against vaccine-related serotypes as well as most of vaccine types than do IgG antibodies. Further studies are needed for the more immunized sera in the children as well as adults.
Subject(s)
Adult , Aged , Child , Humans , Antibodies , Cross Protection , Enzyme-Linked Immunosorbent Assay , Epitopes , Homicide , Immunization , Immunization, Secondary , Immunoglobulin G , Immunoglobulin M , Pneumococcal Vaccines , Streptococcus pneumoniae , Heptavalent Pneumococcal Conjugate VaccineABSTRACT
The desired effect of vaccination is to elicit protective immune responses against infection with pathogenic agents. An inactivated influenza vaccine is able to induce the neutralizing antibodies directed primarily against two surface antigens, hemagglutinin and neuraminidase. These two antigens undergo frequent antigenic drift and hence necessitate the annual update of a new vaccine strain. Besides the antigenic drift, the unpredictable emergence of the pandemic influenza strain, as seen in the 2009 pandemic H1N1, underscores the development of a new influenza vaccine that elicits broadly protective immunity against the diverse influenza strains. Cold-adapted live attenuated influenza vaccines (CAIVs) are advocated as a more appropriate strategy for cross-protection than inactivated vaccines and extensive studies have been conducted to address the issues in animal models. Here, we briefly describe experimental and clinical evidence for cross-protection by the CAIVs against antigenically distant strains and discuss possible explanations for cross-protective immune responses afforded by CAIVs. Potential barriers to the achievement of a universal influenza vaccine are also discussed, which will provide useful guidelines for future research on designing an ideal influenza vaccine with broad protection without causing pathogenic effects such as autoimmunity or attrition of protective immunity against homologous infection.
Subject(s)
Humans , Adaptive Immunity , Antigens, Viral/immunology , Cross Protection , Genome, Viral , Immunity, Innate , Influenza Vaccines/immunology , Influenza, Human/prevention & control , Orthomyxoviridae/genetics , Vaccines, AttenuatedABSTRACT
This study was focusing on evaluating the protection of polyphosphate kinase (ppk) deleted and/or temperature-sensitive (ts) Salmonella Enteritidis (SE) as an attenuated vaccine in chickens. We constructed SEppk, SEts and SEppk::ts mutants and screened those mutants by growth capability in vitro, protection study in mice model and antibody response in chickens. Among the mutants, SEppk::ts-3 was selected because it showed higher growth capability, good protection against highly virulent SE in mice model, and good antibody response in chickens. SEppk::ts-3 also showed good protection against highly virulent SE isolate because it decreased colonization of virulent SE challenge strain in spleen, liver and cecum compared with the non-vaccinated control. The SEppk::ts-3 mutant showed cross-protection against S. Gallinarum (SG) challenge although the its cross-protection rate was a little lower than that of SG9R, a commercial vaccine against SG infection. To use for live attenuated vaccine in chickens, it should further be characterized.
Subject(s)
Animals , Mice , Antibody Formation , Cecum , Chickens , Colon , Cross Protection , Liver , Phosphotransferases , Salmonella enteritidis , Salmonella , SpleenABSTRACT
Despite recent innovative advances in molecular virology and the developments of vaccines, influenza virus remains a serious burden for human health. Vaccination has been considered a primary countermeasure for prevention of influenza infection. Live attenuated influenza vaccines (LAIVs) are particularly attracting attention as an effective strategy due to several advantages over inactivated vaccines. Cold-adaptation, as a classical means for attenuating viral virulence, has been successfully used for generating safe and effective donor strains of LAIVs against seasonal epidemics and occasional pandemics. Recently, the advent of reverse genetics technique expedited a variety of rational strategies to broaden the pool of LAIVs. Considering the breadth of antigenic diversity of influenza virus, the pool of LAIVs is likely to equip us with better options for controlling influenza pandemics. With a brief reflection on classical attenuating strategies used at the initial stage of development of LAIVs, especially on the principles underlying the development of cold-adapted LAIVs, we further discuss and outline other attenuation strategies especially with respect to the rationales for attenuation, and their practicality for mass production. Finally, we propose important considerations for a rational vaccine design, which will provide us with practical guidelines for improving the safety and effectiveness of LAIVs.
Subject(s)
Humans , Antigenic Variation , Cross Protection , Influenza Vaccines , Influenza, Human , Orthomyxoviridae , Pandemics , Reverse Genetics , Seasons , Tissue Donors , Vaccination , Vaccines, InactivatedABSTRACT
The efficacy and immunogenicity of human papillomavirus (HPV) vaccines has proven excellent in several phase 2 and phase 3 trials involving tens of thousand women. Two versions of HPV vaccine had been developed, both target HPV 16 and HPV 18, which involve approximately 70% of cervical cancer. We have summarized the recent review of all randomized controlled trials in which vaccines against HPV were compared with placebo regarding efficacy, safety, and immunogenicity. Both vaccines have an excellent safety profile, are highly immunogenic, and have atributed complete type specific protection against persistent infection and associated lesions in fully vaccinated girls and young women. Data strongly suggest that both vaccines can have a variable level of cross protection against HPV types genetically and antigenically-closely related to vaccine types. Demonstration of cross protection against combined endpoints [cervical intraepithelial neoplasia (CIN) 2/3 and adenocarcinoma in situ] for HPV-31 has been reached for the quadrivalent vaccine. Bivalent HPV vaccine showed significant type-specific cross-protection against CIN2+ associated with HPV-31, HPV-33, and HPV-45. The bivalent vaccine is also registered for above age 26 in Australia, Israel and Korea. In our country, we have already set up the clinical guideline of both vaccines. Although these prophylactic vaccination is likely to provide important gains in the prevention of cervical cancer, we should have need to establish the new screening guideline in post-vaccination period and to make next version of vaccination-guidelines related of specific subgroups of patients who would benefit from the vaccine (women older than 26 years, boys, and men).
Subject(s)
Female , Humans , Adenocarcinoma , Australia , Uterine Cervical Dysplasia , Cross Protection , Human papillomavirus 16 , Human papillomavirus 18 , Israel , Korea , Mass Screening , Papillomavirus Vaccines , Transcutaneous Electric Nerve Stimulation , Uterine Cervical Neoplasms , Vaccination , VaccinesABSTRACT
This study evaluated the possibility of inoculation and reinoculation with a trypanosomatid isolated from bats that is morphologically, biologically and molecularly similar to Trypanosoma cruzi, to protect against infection by virulent strains. Non-isogenic mice were divided into 24 groups that received from zero to three inoculations of Trypanosoma cruzi-like strain RM1, in the presence or absence of Freunds adjuvant, and were challenged with the VIC or JG strains of Trypanosoma cruzi. Parasitemia and survival were monitored and animals were sacrificed for histopathological analysis. Animals immunized with Trypanosoma cruzi-like strain RM1 presented decreased parasitemia, independently of the number of inoculations or the presence of adjuvant. In spite of this reduction, these animals did not present any protection against histopathological lesions. Severe eosinophilic infiltrate was observed and was correlated with the number of inoculations of Trypanosoma cruzi-like strain RM1. These findings suggest that prior inoculation with this strain did not protect against infection but, rather, aggravated the tissue inflammatory process.
Este trabalho avaliou a possibilidade da inoculação e reinoculação de um tripanossomatídeo isolado de morcego, morfológica, biológica e molecularmente semelhante ao Trypanosoma cruzi, na proteção contra a infecção por cepas virulentas. Camundongos não-isogênicos foram divididos em 24 grupos, que receberam de zero a três inóculos da cepa RM1 de Trypanosoma cruzi-like, na presença ou ausência de adjuvante de Freund e desafiados com as cepas de Trypanosoma cruzi VIC ou JG. Acompanhou-se a parasitemia e a sobrevida e os camundongos foram sacrificados para análise histopatológica. Os animais imunizados com a cepa RM1 de Trypanosoma cruzi-like apresentaram redução da parasitemia, independente do número de inóculos ou presença de adjuvante. Apesar dessa redução, os animais não apresentaram proteção contra lesões histopatológicas e observaram-se intensos infiltrados eosinofílicos que foram correlacionados com o número de inóculos da cepa RM1 de Trypanosoma cruzi-like. Sugere-se que a inoculação prévia dessa cepa, ao invés de proteger contra a infecção, agravou o processo inflamatório tecidual.