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Tuberculosis (TB) is one of the top 10 causes of death in humans worldwide. The most important causative agents of TB are bacteria from the Mycobacterium tuberculosis complex (MTC), although nontuberculous mycobacteria (NTM) can also cause similar infections. The ability to identify and differentiate MTC isolates from NTM is important for the selection of the correct antimicrobial therapy. Immunochromatographic assays with antibodies anti-MPT64 allow differentiation between MTC and NTM since the MPT64 protein is specific from MTC. However, studies reported false-negative results mainly due to mpt64 63-bp deletion. Considering this drawback, we selected seven human antibody fragments against MPT64 by phage display and produced them as scFv-Fc. Three antibodies reacted with rMPT64 mutant (63-bp deletion) protein and native MPT64 from M. tuberculosis H37Rv in ELISA and Western blot. These antibodies are new biological tools with the potential for the development of TB diagnosis helping to overcome limitations of the MPT64-based immunochromatographic tests currently available.

Despite common occurrence and importance of canine distemper disease the majority of tests currently available for diagnosis are hampered by either low sensitivity or specificity. In this study it was evaluated antigenic and immunogenic characteristics of a conserved region of nucleocapsid protein of canine distemper virus (rCDV NP) expressed in Escherichia coli employing a codon optimized synthetic gene. The expression of rCDVNP in Star strain (mean 300μg/mL, purified) was confirmed by SDS-PAGE and Western blot analysis by using His-Tag monoclonal antibodies. Western blot and ELISA, employing positive and negative control dog sera, demonstrated the rCDVNP antigenicity. The rCDVNP was inoculated in hens and immunoglobulin Y (IgY) was purified from the egg yolk. The mean yield of IgY was 28.55mg/mL. IgY reacted with the recombinant protein as demonstrated by Western blot and ELISA assays. In summary, our findings demonstrated that rCDVNP is antigenic since CDV positive dog sera recognized the protein in vitro. Additionally, the rCDVNP proved to be immunogenic in hens being possible to isolate a high concentration of specific IgY antibodies from the egg yolk. Taken together, these results indicate that the rCDVNP along with the specific IgY could be useful tools for development of the canine distemper immunodiagnostic assays. RESUMO: Apesar da ocorrência comum e importância da cinomose canina, a maioria dos testes atualmente disponíveis para diagnóstico são prejudicados pela baixa sensibilidade ou especificidade. Neste estudo foram avaliadas características antigênicas e imunogênicas de uma região conservada da proteína do nucleocapsídeo do virus da cinomose canina (rCDV NP) expressa em Escherichia coli empregando um gene sintético e codons otimizados. A expressão na cepa Star (média de 300μg/mL, purificada) foi confirmada por SDS-PAGE e Western blot utilizando anticorpos monoclonais anti-His-Tag. A antigenicidade da rCDVNP foi demonstrada por western blot e ELISA empregando soros de cães positivos e negativos. A rCDVNP foi inoculada em galinhas e imunoglobulina Y (gY) foi obtida e purificada a partir da gema. A produção média de IgY foi 28.55mg/mL. Anticorpos IgY reagiram com a proteína recombinante, quando analisados por Western blot e ELISA. Em resumo, nossos achados demonstram que a rCDVNP produzida é antigênica, uma vez que os anticorpos de soro de cães positivos para CDV reconheceram a proteína in vitro. Além disso, a rCDVNP foi imunogênica em galinhas, sendo possível isolar anticorpos IgY específicos a partir da gema do ovo em altas concentrações. Tomados em conjunto, estes resultados indicam que a rCDVNP juntamente com a IgY específica podem ser ferramentas úteis para elaborar ensaios de imunodiagnóstico de cinomose canina.

A vacinação é a forma mais utilizada para prevenir a bronquite infecciosa causada pelo vírus da bronquite infecciosa das galinhas (IBV). Contudo, as vacinas convencionais são incapazes de diferenciar aves infectadas de vacinadas. No presente trabalho foi construído, caracterizado, e avaliado como candidato vacinal, um adenovírus recombinante expressando o gene N do IBV. O gene N foi clonado em um adenovírus humano tipo 5 defectivo e transfectado para as células HEK-293A para gerar rAd5_N. Após o vetor ser obtido como esperado e a confirmação da expressão da proteína N em HEK-293ª, foi realizada inoculação pela via oculo-nasal na dose de 107 TCID50/0,1mL para imunização de galinhas livres de patógenos específicos (SPF). A resposta imunológica do Ad5_N e a proteção contra o desafio ao IBV foram avaliadas e comparadas com uma vacina viva comercial. Não foram detectados anticorpos anti-IBV em aves vacinadas com o Ad5_N. A vacina comercial induziu anticorpos detectáveis a partir do 7º dia pós-vacinal. Em aves vacinadas com o Ad5_N não houve aumento na expressão de IFNγ. Neste estudo, o rAd5_N obtido não conferiu proteção contra desafio com IBV-M41. Os resultados indicam a necessidade de avaliar adenovírus recombinantes expressando outros genes do IBV Made available in DSpace on 2019-11-13T18:16:37Z (GMT). No. of bitstreams: 1 Ritterbusch2019.pdf: 730975 bytes, checksum: 0acd3b65f8f3795195d9192f02da5e57 (MD5) Previous issue date: 2019

Background : Mycoplasma hyopneumoniae is the etiological agent of the Swine Mycoplasmal Pneumonia (SMP), one of the most economically significant diseases in the swine industry worldwide. Commonly used vaccines for SMP control consist of inactivated whole cells (bacterins). These vaccines are efficacious against M. hyopneumoniae challenge, but do not prevent colonization by the pathogen or completely eliminate pneumonia. P97 adhesin is conserved in the M. pneumoniae virulent strains, therefore it is an attractive target to be used in recombinant vaccines against M. hyopneumoniae. The aim of the present study was to evaluate protection afforded by rLTB-R1, a recombinant chimera composed by LTB fused with the R1 repeat region of P97 adhesin of M. hyopneumoniae , in specific-pathogen-free (SPF) piglets vaccinated by intranasal or intramuscular route and challenged with a pathogenic strain of M. hyopneumoniae . Materials, Methods & Results : PCR products of the LTB and R1 coding sequences were fused, then cloned into pETDEST42™ expression vector. The rLTB-R1 was expressed in Escherichia coli BL21 (DE3) Salt induction (SI).They were allocated into three groups: four piglets were intranasally vaccinated with 1 mg of rLTB-R1 solubilized in 1 mL of PBS at 0 and 14 days (IN rLTB-R1 group); four piglets were intramuscularly vaccinated with 1 mg of rLTB-R1 solubilized in 1 mL of PBS at 0 and 14 days (IM rLTB-R1 group);three piglets were intranasally and intramuscularly inoculated with 1 mL of PBS (control group).Two weeks after the last immunization (28 day), piglets were intratracheally challenged with 10 mL of a suspension containing 10 9 color-changing unit (CCU) of pathogenic M. hyopneumoniae 7448 strain on three consecutive days. Until the challenge (28 days), intranasal and intramuscular vaccination with rLTB-R1 induced seroconversions of anti-R1 systemic antibodies of 1.6 and 4.6 ×, respectively. The IN rLTB-R1 group had no pulmonary lesion, rLTB-R1 conferred protection against experimental SMP. On the other hand, IM rLTB-R1 and control groups had on average 7.24% and 8.46% of pulmonary lesion, respectively, showing that intramuscular vaccination with rLTB-R1 did not confer protection. Discussion : The rLTB-R1, when intranasally administrated to mice, elicited production of anti-R1 IgA in trachea and bronchi as well as specific Th1 response, suggesting an adequate stimulation of the mucosal immune system. We believe that rLTB-R1 induced a similar immune response in piglets intranasally vaccinated, conferring protection against experimental SMP. The present study, the rLTB-R1 alone, without any chemical adjuvant, stimulated a significant seroconversion of anti-R1 systemic antibodies in pigs intramuscularly vaccinated, showing the potential of LTB as a parenteral adjuvant in swine vaccination.Previous work has shown that the intramuscular administration route was evaluated in pigs because mice intramuscularly vaccinated with rLTB-R1 presented significant levels of anti-R1 IgA in trachea and bronchi, suggesting that rLTB can stimulate some degree of mucosal immunity even if not delivered by a mucosal route.However, in the present study, piglets intramuscularly vaccinated with rLTB-R1 presented high levels of anti-R1 systemic antibodies, they were not protected.On the other hand, intranasal vaccination of piglets with rLTB-R1 elicited low levels of anti-R1 systemic antibodies (1.6 × at 28 days), but it conferred full protection against experimental SMP. The present study demonstrated that intranasal vaccination of piglets with rLTB-R1 conferred protection against experimental SMP. A more detailed analysis of the protective immune response induced by rLTB-R1 in pigs is currently being performed.

Botulism is a paralytic disease caused by the intoxication of neurotoxins produced by Clostridium botulinum. Among the seven immunologically distinct serotypes of neurotoxins (BoNTs A − G), serotypes C and D, or a chimeric fusion termed C/D or D/C, are responsible for animal botulism. The most effective way to prevent botulism in cattle is through vaccination; however, the commercially available vaccines produced by detoxification of native neurotoxins are time-consuming and hazardous. To overcome these drawbacks, a non-toxic recombinant vaccine was developed as an alternative. In this study, the recombinant protein vaccine was produced using an Escherichia coli cell-based system. The formaldehyde-inactivated E. coli is able to induce 7.45 ± 1.77 and 6.6 ± 1.28 IU/mL neutralizing mean titers against BoNTs C and D in cattle, respectively, determined by mouse neutralization bioassay, and was deemed protective by the Brazilian legislation. Moreover, when the levels of anti-BoNT/C and D were compared with those achieved by the recombinant purified vaccines, no significant statistical difference was observed. Cattle vaccinated with the commercial vaccine developed 1.33 and 3.33 IU/mL neutralizing mean titers against BoNT serotypes C and D, respectively. To the best of our knowledge, this study is the first report on recombinant E. coli bacterin vaccine against botulism. The vaccine was safe and effective in generating protective antibodies and, thus, represents an industry-friendly alternative for the prevention of cattle botulism.

Botulism is a potentially fatal intoxication caused by botulinum neurotoxins (BoNTs) produced mainly by Clostridium botulinum. Vaccination against BoNT serotypes C and D is the main procedure to control cattle botulism. Current vaccines contain formaldehyde-inactivated native BoNTs, which have a time-consuming production process and pose safety risks. The development of non-toxic recombinant vaccines has helped to overcome these limitations. This study aims to evaluate the humoral immune response generated by cattle immunized with non-purified recombinant fragments of BoNTs C and D. Cattle were vaccinated in a two-dose scheme with 100, 200 and 400 &micro, g of each antigen, with serum sampling on days 0, 56, 120, and 180 after vaccination. Animals who received either 200 or 400 &mu, g of both antigens induced titers higher than the minimum required by the Brazilian ministry of Agriculture, Livestock and Food Supply and achieved 100% (8/8) seroconversion rate. Animals vaccinated with commercial toxoid vaccine had only a 75% (6/8) seroconversion rate for both toxins. Animals that received doses containing 400 &micro, g of recombinant protein were the only ones to maintain titers above the required level up until day 120 post-vaccination, and to achieve 100% (8/8) seroconversion for both toxins. In conclusion, 400 &micro, g the recombinant Escherichia coli cell lysates supernatant was demonstrated to be an affordable means of producing an effective and safe botulism vaccine for cattle.

Made available in DSpace on 2014-09-30T18:18:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-01Bitstream added on 2014-10-01T14:03:36Z : No. of bitstreams: 1 S0102-09352014000100001.pdf: 134074 bytes, checksum: 0d75227daf3dfeeb20a54373c2b4f89d (MD5) No Brasil existem poucos estudos sobre a ocorrência da infecção pelo vírus da imunodeficiência felina (FIV), assim como a determinação dos subtipos circulantes, o que é indispensável para o desenvolvimento de vacinas e novos testes diagnósticos. O presente trabalho investigou a ocorrência da infecção pelo FIV entre os anos de 2010 e 2011 em gatos domésticos submetidos a atendimento clínico na cidade de Pelotas e região. Amostras de sangue total de 70 animais, incluindo suspeitos (28) ou não suspeitos (42) da infecção pelo FIV, foram submetidas à reação de PCR nested. Os resultados indicaram uma frequência de infecção de 15,7% (11/70) e a análise dos fatores associados (sexo, idade e condição clínica) evidenciou uma maior ocorrência em gatos com idade superior a 10 anos e acometidos por infecções crônicas e recidivantes. Oito amostras positivas na PCR nested foram submetidas a sequenciamento genômico e somente o subtipo B foi detectado na região estudada. In Brazil there are few studies on the occurrence of the feline immunodeficiency virus (FIV) infection and its subtypes, which are essential for the development of vaccines and new diagnostic tests. The present study investigated the occurrence of the FIV infection between 2010 and 2011 in domestic cats submitted to medical attendance in the city of Pelotas and nearby area. Total blood samples of seventy cats, suspected (28) or not (42) of infection by FIV were analyzed by nested PCR in order to perform a diagnosis. The results pointed to a FIV infection frequency of 15.7% (11/70) and the analysis of the risk factors related to infection (sex, age and clinical condition) evidenced a greater occurrence in cats up to 10 years of age with chronic and recurrent infections. Eight samples found positive by nested PCR were submitted to DNA sequencing indicating that only the subtype B was detected in the studied region. Universidade Federal de Pelotas Faculdade de Veterinária Universidade Estadual Paulista Instituto de Biociências Universidade Estadual Paulista Instituto de Biociências

Canine coronavirus (CCoV) has been reported causing enteric disease mainly in young pups. In this study, to investigate immunity and exposure to CCoV, was estimated the frequency of serum antibodies to CCoV in 121 dogs in the Pelotas, South of Brazil, by serum neutralization test (SN): 22 had not been vaccinated, 69 had been vaccinated at least once, and 30 had unknown vaccination history. Antibodies were present in 47,8% (33/69) of the vaccinated dogs, in 45,5% (10/22) of the unvaccinated, and in 43,3% (13/30) of the dogs with unknown historical vaccination. There was no significant relationship between these antibodies and sex, age, habitat, and season of collection. The results proved the circulation of the CCoV among this dog population and indicated that the infection affects a significant group of animals. The large proportion of seronegative vaccinated dogs indicates failure of CCoV vaccine in inducing neutralizing antibodies, suggesting that immunizations to CCoV should be reevaluated. The authors indicate the need for further studies in order to evaluate the impact of the infection caused by CCoV, as well as to propose and evaluate preventive measures. Coronavírus canino (CCoV) foi relatado como causa de doença entérica principalmente em cães jovens. Nesse estudo, para investigar imunidade e exposição ao CCoV, foi estimado a frequência de anticorpos em 121 cães de Pelotas, sul do Brasil, pelo teste de soro-neutralização (SN): 22 não haviam sido vacinados, 69 haviam sido vacinados com pelo menos uma dose, e 30 possuíam histórico de vacinação desconhecido. Foram detectados anticorpos em 47,8% (33/69) dos cães vacinados, em 45,5% (10/22) dos não vacinados, e em 43,3% (13/30) dos cães com histórico de vacinação desconhecido. Não houve associação significativa entre os anticorpos e sexo, idade, habitação e estação da coleta. Os resultados confirmam a circulação do CCoV entre essa população de cães e indicam que a infecção acomete população significativa de animais. A grande proporção de cães vacinados soronegativos indica falha da vacina em indução de anticorpos neutralizantes, sugerindo que as imunizações para CCoV devam ser reavaliadas. Os autores por meio de seus dados indicam ainda a necessidade de posteriores estudos para avaliar o impacto da infecção causada pelo CCoV, bem como para avaliar e propor mediadas preventivas.

Adjuvants play an important role in vaccine formulations by increasing their immunogenicity. In this study, the phenolic compound-rich J fraction (JFR) of a Brazilian green propolis methanolic extract stimulated cellular and humoral immune responses when co-administered with an inactivated vaccine against swine herpesvirus type 1 (SuHV-1). When compared to control vaccines that used aluminium hydroxide as an adjuvant, the use of 10 mg/dose of JFR significantly increased (p < 0.05) neutralizing antibody titres against SuHV-1, as well as the percentage of protected animals following SuHV-1 challenge (p < 0.01). Furthermore, addition of phenolic compounds potentiated the performance of the control vaccine, leading to increased cellular and humoral immune responses and enhanced protection of animals after SuHV-1 challenge (p < 0.05). Prenylated compounds such as Artepillin C that are found in large quantities in JFR are likely to be the substances that are responsible for the adjuvant activity.

Bovine herpesviruses 1 and 5 (BoHV-1 and BoHV-5) are economically important pathogens, associated with a variety of clinical syndromes, including respiratory and genital disease, reproductive failure and meningoencephalitis. The standard serological assay to diagnose BoHV-1 and BoHV-5 infections is the virus neutralization test (VNT), a time consuming procedure that requires manipulation of infectious virus. In the present study a highly sensitive and specific single dilution indirect ELISA was developed using recombinant glycoprotein D from BoHV-5 as antigen (rgD5ELISA). Bovine serum samples (n = 450) were screened by VNT against BoHV-5a and by rgD5ELISA. Compared with the VNT, the rgD5ELISA demonstrated accuracy of 99.8%, with 100% sensitivity, 96.7% specificity and coefficient of agreement between the tests of 0.954. The rgD5ELISA described here shows excellent agreement with the VNT and is shown to be a simple, convenient, specific and highly sensitive virus-free assay for detection of serum antibodies to BoHV-5.

Glycoprotein D (gD) is essential for attachment and penetration of Bovine herpesvirus 5 (BoHV-5) into permissive cells, and is a major target of the host immune system, inducing strong humoral and cellular immune responses. The aim of this study was to evaluate in mice the immunogenicity of recombinant BoHV-5 gD (rgD5) expressed in Pichia pastoris. Vaccines formulated with rgD5 alone or adjuvanted with Montanide 50 ISA V2; Emulsigen or Emulsigen-DDA was administered intramuscularly or subcutaneously. Almost all formulations stimulated a humoral immune response after the first inoculation. The only exception was observed when the rgD5 was administered subcutaneously without adjuvant, in this case, the antibodies were observed after three doses. Higher titers of neutralizing antibodies were obtained with the three oil-based adjuvant formulations when compared to non-adjuvanted vaccine formulations. The rgD5 vaccine stimulated high mRNA expression levels of Th1 (INF-γ) and pro-inflammatory cytokines (IL-17, GM-CSF). The results demonstrated that the recombinant gD from BoHV-5 conserved important epitopes for viral neutralization from native BoHV-5 gD and was able to elicit mixed Th1/Th2 immune response in mice.

A peroxidase linked assay (PLA) was designed to screen bovine sera for the presence of specific antibodies against bovine leukosis virus (BLV). Out of 201 samples of bovine sera analyzed, 52.2% were considered positive by PLA, 26.4% by AGID, and 38.9% by ELISA. Western blotting analyses excluded 27 samples found to be positive by PLA. PLA showed 100% of sensitivity when compared with AGID and ELISA. Specificity was 64.8% and 78%, respectively (kappa coefficients were 0.70 and 0.83). These findings indicate that PLA can be used as an alternative method for the diagnosis of BLV infection in cattle.

A bronquite infecciosa das galinhas (IB) é uma enfermidade altamente contagiosa que acomete aves de todas as idades e causa grandes prejuízos na avicultura. O trabalho descreve uma metodologia para expressão da glicoproteína S1 do vírus da bronquite infecciosa das galinhas (IBV) em Pichia pastoris e Escherichia coli. Para P. pastoris o gene foi amplificado por RT-PCR, com posterior clonagem e expressão no vetor pPICZαB. Para E. coli, foi elaborado o gene sintético a partir de uma sequência consenso de amostras de campo nacionais e internacionais, clonado e expresso no vetor pAE. Após indução dos clones, a proteína S1 foi identificada pelas técnicas de Dot blotting e Western blotting. A proteína expressa apresentou reatividade frente a soros de aves positivas para IBV, evidenciando sua antigenicidade.

To investigate the exposure of the Newcastle disease virus (NDV), infectious bursal disease virus (IBDV) and avian poxvirus (APV) in Magellanic penguins found on the beaches in Southern regions of Brazil, the frequency of serum antibodies was estimated in 89 samples taken during 2005 and 2006. All the penguins were negative for the presence of antibodies against NDV by hemagglutination inhibition test and to APV by indirect ELISA. The reactivity was similar to the positives controls using ELISA kit for the IBDV made in the chickens in 50 samples. This reactivity also was demonstrated in 42 samples using agar gel immunodiffusion. No clinical signs related to IBDV infection were observed. The results indicated the absence of infection by NDV and APV but suggested IBDV exposure in the population of penguins studied.

The strangles is an infectious disease that affects horses from all ages and causes important economic losses in the equine-related business. The aim of this work was to evaluate the immunogenicity of the recombinant M protein from Streptococcus equi (rSeM) co-administered with the recombinant heat-labile enterotoxin B subunit from Escherichia coli (rLTB) in mice and horses. A total of 72 female Balb-c mice were divided into eight groups and 18 horses were divided into six groups. The animals were inoculated by intramuscular (IM) or intranasal (IN) routes with different treatments of rSeM, rLTB and/or Al(OH)3. The results obtained in both species, independent of administration routes, demonstrated that rSeM + rLTB had higher levels of specific serum immunoglobulins, however, in mucosal immunity the increase was not identified. Thus, the use of rSeM as vaccine antigen and rLTB as adjuvant can be a potential tool in the control of equine strangles.

BACKGROUND The B subunit of Escherichia coli heat-labile enterotoxin (LTB) is a potent mucosal immune adjuvant. However, there is little information about LTB's potential as a parenteral adjuvant. OBJECTIVES We aimed at evaluating and better understanding rLTB's potential as a parenteral adjuvant using the fused R1 repeat of Mycoplasma hyopneumoniae P97 adhesin as an antigen to characterise the humoral immune response induced by this construct and comparing it to that generated when aluminium hydroxide is used as adjuvant instead. METHODS BALB/c mice were immunised intraperitoneally with either rLTBR1 or recombinant R1 adsorbed onto aluminium hydroxide. The levels of systemic anti-rR1 antibodies (total Ig, IgG1, IgG2a, and IgA) were assessed by enzyme-linked immunosorbent assay (ELISA). The ratio of IgG1 and IgG2a was used to characterise a Th1, Th2, or mixed Th1/Th2 immune response. FINDINGS Western blot confirmed rR1, either alone or fused to LTB, remained antigenic; anti-cholera toxin ELISA confirmed that LTB retained its activity when expressed in a heterologous system. Mice immunised with the rLTBR1 fusion protein produced approximately twice as much anti-rR1 immunoglobulins as mice vaccinated with rR1 adsorbed onto aluminium hydroxide. Animals vaccinated with either rLTBR1 or rR1 adsorbed onto aluminium hydroxide presented a mixed Th1/Th2 immune response. We speculate this might be a result of rR1 immune modulation rather than adjuvant modulation. Mice immunised with rLTBR1 produced approximately 1.5-fold more serum IgA than animals immunised with rR1 and aluminium hydroxide. MAIN CONCLUSIONS The results suggest that rLTB is a more powerful parenteral adjuvant than aluminium hydroxide when administered intraperitoneally as it induced higher antibody titres. Therefore, we recommend that rLTB be considered an alternative adjuvant, even if different administration routes are employed.