Effect of Low Dose of Chicken Infectious Anemia Virus in Attenuated Vaccine on SPF Chicken Body Weight and Vaccine Immune Antibody / 病毒学报

In order to observe the effect of the immune and weight of chickens after use the attenuated vaccine with low dose of chicken infectious anemia virus (CIAV). In this study, the effects of low dose of CIAV on the weight of SPF chickens and NDV antibody production were observed by simulated experiments. The results showed that 10 EID50 and 5 EID50 CIAV per plume attenuated NDV vaccines were used to cause the weight loss of SPF chickens. Compared with the use of the non contaminated vaccine group, it has significant difference. And NDV antibody levels compared with the use of the non contaminated groups also decreased after use the vaccine with two doses of CIAV contaminated. It has significant difference. A certain proportion of CIAV antibody positive was detected at the beginning of the second week after use the NDV vaccine with two doses of CIAV contaminated. The detection of a high proportion of CIAV nucleic acid was detected in the first week after the use of a contaminated vaccine. The results of the study demonstrate the effects of CIAV pollution on the production and immune function of SPF chickens, and it is suggested that increasing the detection of viral nucleic acid can help save time and improve the detection rate in the detection of exogenous virus contamination by SPF chicken test method.

The occurrence of orthoreovirus, rotavirus and chicken anemia virus in chickens of the poultry industry in Minas Gerais, Brazil / Ocorrência de orthoreovirus, rotavirus e vírus da anemia das galinhas em frangos de corte da indústria avícola de Minas Gerais

Fifty-four fecal samples taken from broiler chickens from 1 to 45 days of age, and of pullets from 10 to 13 weeks of age, original from eight different poultry regions in the state of Minas Gerais, Brazil, were collected from March 2008 to January 2010 for avian Orthoreovirus (ARV) and avian Rotavirus (AvRV) analyses. For the assay of ARV, RNA was immediately extracted (Trizolâ) and transcribed into cDNA for assaying in a nested-PCR with ARV-specific primers. For AvRV, polyacrylamide gel electrophoresis (PAGE) was performed with RNA extracts obtained by phenol-chloroform extraction. CAV was additionally investigated through a nested-PCR of thymus and spleen. Results found 5.55% positive for ARV and 9.25% for AvRV. Also, CAV and ARV genomes were detected in co-infection, in a highly prostrated and claudicating chicken flock. No ARV or AvRV infections were detected in pullets. Material of a clinically affected flock was inoculated into SPF embryos, resulting in embryonic hemorrhage, whitish foci in the chorio-allantoic membrane and death. Sequencing of ARV amplicons and isolate cDNA grouped local strains with the ARV S1133 strain, historically used in live vaccines, suggesting the continued circulation of this vaccine virus strain in intensive poultry regions. Detection rates for ARV and AvRV, as well as the presence of CAV, were additionally indicative of failing biosecurity strategies for the intensive poultry regions examined.

Avaliou-se a ocorrência de Orthoreovirus (ARV) e Rotavirus (AvRV) aviários na avicultura industrial de Minas Gerais. Foram colhidas cinquenta e quatro amostras de fezes de frangos de corte entre um e 45 dias e de frangas de postura de 10 a 13 semanas de idade. Para análise de ARV, o RNA foi imediatamente extraído (Trizol), transcrito em cDNA e avaliado em uma PCR com oligonucleotídeos iniciadores específicos para ARV. Para a investigação de AvRV, os extratos de RNA foram obtidos por fenol-clorofórmio e submetidos à eletroforese em gel de poliacrilamida. Todas as amostras foram também avaliadas para o DNA do vírus da anemia das galinhas (CAV) em uma nested-PCR específica. Em frangos de corte, a positividade encontrada para ARV foi de 5,55% e para AvRV de 9,25%. CAV foi detectado em coinfecção em um plantel com refugagem, claudicação e prostração. Nenhuma amostra de poedeiras foi positiva para ARV ou AvRV. Material de plantel com sinais clínicos foi purificado e inoculado em ovos SPF embrionados, sendo obtidas lesões hemorrágicas e focos brancos na membrana cório-alantóide. O sequenciamento dos produtos de PCR e de embrião agrupou os isolados de ARV com a estirpe S1133, historicamente usada como vacina viva. Os resultados sugerem a continuada circulação da infecção por estirpes assemelhadas a ARV S1133 nas regiões de avicultura industrial. Os índices de detecção de ARV, AvRV e CAV indicam que a intensificação nas regiões produtoras tem resultado em falhas de biosseguridade.

Development and characterization of a potential diagnostic monoclonal antibody against capsid protein VP1 of the chicken anemia virus

Chicken anemia virus (CAV) is an important viral pathogen that causes anemia and severe immunodeficiency syndrome in chickens worldwide. In this study, a potential diagnostic monoclonal antibody against the CAV VP1 protein was developed which can precisely recognize the CAV antigen for diagnostic and virus recovery purposes. The VP1 gene of CAV encoding the N-terminus-deleted VP1 protein, VP1Nd129, was cloned into an Escherichia (E.) coli expression vector. After isopropyl-beta-D-thiogalactopyronoside induction, VP1Nd129 protein was shown to be successfully expressed in the E. coli. By performing an enzyme-linked immunoabsorbent assay using two coating antigens, purified VP1Nd129 and CAV-infected liver tissue lysate, E3 monoclonal antibody (mAb) was found to have higher reactivity against VP1 protein than the other positive clones according to the result of limiting dilution method from 64 clones. Using immunohistochemistry, the presence of the VP1-specific mAb, E3, was confirmed using CAV-infected liver and thymus tissues as positive-infected samples. Additionally, CAV particle purification was also performed using an immunoaffinity column containing E3 mAb. The monoclonal E3 mAb developed in this study will not only be very useful for detecting CAV infection and performing histopathology studies of infected chickens, but may also be used to purify CAV particles in the future.

Detection of chicken anemia virus and infectious bursal disease virus co-infection in broilers / Detecção do virus da anemia das galinhas em coinfecção com o vírus doença infecciosa bursal em frangos

This survey aimed to investigate chicken anemia virus (CAV) in broilers flocks experimenting retarded growth and increasing mortality since the fourth day of age. Clinically, chickens presented depression, paleness, depigmentation and retarded growth. At necropsy, chickens presented CAV-compatible lesions. Samples from liver, spleen and thymus were tested by PCR for a 675-bp fragment of the CAV VP-1 gene, and all tested samples were positive. Serological and molecular techniques did not detect other pathogens, such as adenovirus, reovirus, astrovirus, infectious bursal disease and avian infectious bronchitis virus. These results showed that chicken anemia virus (CAV) may occur since the first few days of life in broilers - a fact not as yet reported -, associated with high pathogenic Infectious Bursal Disease Virus (IBDV) vaccine strain may induce a persistent growth retarded for several weeks in broilers.

Este estudo investigou a manifestação do vírus da Anemia Infecciosa das Aves (VAIA) em lotes de frangos que apresentavam retardo no crescimento e aumento da mortalidade observado a partir do quarto dia de idade. Clinicamente, as aves apresentavam depresão, palidez, despigmentação e retardo de crescimento. À necropsia, as aves apresentavam lesões compatíveis com a infecção pelo vírus da Anemia infecciosa das aves (VAIA). Amostras de fígado, baço e timo foram examinadas por PCR que amplifica um frangmento de 675 pb do gene VP-1 do VAIA. Todos os órgãos examinados foram positivos para o vírus da Anemia Infecciosa das Aves. Os demais patógenos, como adenovírus, reovírus, astrovírus, vírus da doença infecciosa bursal e coronavírus aviário não foram detectados pelas diferentes técnicas laboratoriais, como sorologia, PCR ou PAGE. Os resultados mostraram que o vírus da Anemia Infecciosa das Aves (VAIA) pode manifestar-se clinicamente nos primeiros dias de vida dos frangos – um fato ainda não reportado – associado ao vírus vacinal da doença infecciosa bursal (DIB) cepa forte pode induzir um persistente retardo de crescimento, por várias semanas, em frangos.

Anti-tumor effects on human laryngeal carcinoma Hep-2 of recombinant fowlpox virus expressing chicken anemia virus Apoptin gene / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate the anti-tumor effects and the mechanism of the recombinant fowlpox virus expressing Apoptin gene on human laryngeal carcinoma Hep-2.@*METHOD@#Hep-2 cells cultured in vitro were infected with vFVApoptin. The anti-tumor effects on Hep-2 cells were measured through MTT staining and, the mitochondrial trans-membrane potential (delta psi m) and reactive oxygen species (ROS) were analyzed by flow cytometry. Western blot was used to detect the release of cytochrome c (Cyto c). Caspase-3/9 activities were measured by colorimetric assay.@*RESULT@#vFVApoptin could restrain Hep-2 cells significantly and, had the function of down-regulating delta psi m, up-regulating ROS, promoting Cyto c release and activating Caspase-3/9.@*CONCLUSION@#Cyto c were released from mitochondria by the function of up-regulating ROS of vFVApoptin. Cyto c triggered Caspase-9 and, after the activation of Caspase-9, downstream apoptotic factors, such as caspase-3, were activated. Eventually, Hep-2 cells were suppressed by mitochondrial pathway apoptosis induced by vFVApoptin.

Lesions in the thymus and bone marrow in chicks with experimentally induced chicken infectious anemia disease

One-day-old SPF chicks were inoculated with the Cux-l strain of chicken infectious anemia virus (CIAV), and the clinical development of disease and its macroscopic and microscopic alterations in the thymus and bone marrow, were observed. Tissue sections of thymus and bone marrow were stained using the streptavidin-biotin peroxidase method and examined under light microscope for evaluation of antigenic intensities in tissues. Those findings were then compared with blood parameters and ELISA results obtained through collected sera during sacrifice procedures. We sought to determine: the localization of viral antigens in thymus and bone marrow tissues after inoculation, the correlation between antigen intensities and hematologic, serologic and histopathologic findings, definitive diagnostic criteria using histopathologic and immunoperoxidase methods, and the reliability of these methods in the diagnosis of CIAV infection. For this purpose, 83, one-day-old SPF chicks were used. The birds were divided into experimental (n = 52) and control (n = 26) groups. A virus dose of TCID50 of 100,000/ml was administered intramuscularly to every bird in the experimental group. Based on the results of this study, we have suggested that clinical examination, along with macroscopic and microscopic evaluation of the thymus and bone marrow, maybe undertaken starting from day 7 post-inoculation (PI). ELISA, might be of value, as it might give consistent results starting from day 14 PI. However, the most reliable results were obtained through examination of thymus and bone marrow sections from infected birds stained by immunoperoxidase technique, as early as day 4 PI.

Detección de títulos de anticuerpos contra anemia infecciosa aviar y su relación con otros virus inmunosupresores en pollos de engorde: estado Zulia Venezuela / Detection of chicken infectious Anemia antibodies and their relationship with other immunosuppressor virus in broilers chicken: Zulia state Venezuela

En Venezuela, la incidencia de enfermedades respiratorias virales e inmunosupresoras son dos de los mayores problemas en la industria avícola nacional, y hasta el momento no se cuenta con suficiente información epidemiológica al respecto que ayude a establecer medidas de control, por lo que el objetivo de esta investigación fue determinar serológicamente la presencia de anemia infecciosa aviar, reovirus y gumboro, y su relación entre ellas, así como determinar el nivel de anemia en las aves evaluadas. Se tomaron muestras de aproximadamente 14 a 15 aves, de forma semanal a diferentes edades (1, 7, 14, 21, 28, 35 y 42 días), en tres granjas comerciales, tomándose un total de 295 aves. Los títulos de anticuerpos se midieron a través de la prueba ELISA, y el nivel de anemia, por la técnica de microhematocrito. Se detectaron porcentajes de anticuerpos séricos: 90,8 por ciento (268/295) para anemia infecciosa aviar; 82,4 por ciento (244/295) para reovirus y 97 por ciento (286/295) para la enfermedad infecciosa de la bursa. En cuanto a los valores de hematocrito se encontró en forma general que, el 19,6 por ciento (58/295) de las aves evaluadas presentaron anemia, mostrando valores de hematocrito entre 20 y 27 por ciento. Se observó una correlación positiva altamente significativa entre la anemia infecciosa aviar y los otros virus inmunosupresores estudiados, con gumboro (r=0,437; P<0,0001) y reovirus (r=0,312; P<0,0001). Los resultados obtenidos en este trabajo permiten demostrar la presencia del virus de la anemia infecciosa aviar en pollos de engorde en la región, de manera aislada o asociada con reovirus y gumboro, que pudiesen estar afectando en forma subclínica o clínica las granjas avícolas zulianas.

The incidence of viral respiratory and immunosuppressant diseases are two of the biggest problems in the Venezuelan poultry industry, however in the country, there is not enough epidemiological information that helps to establish control measures. The aim of this research was to determine the presence of serological chicken anemia virus, reovirus and gumboro, and it´s correlation between them as well as to determine the level of anemia in the evaluated birds. In this research, approximately fourteen or fifteen (14 or 15) birds were tested weekly and at different ages (1; 7; 14; 21; 28; 35 y 42 days), in three commercial farms. The samples were taken from a total of 295 birds. The viral antibodies were determined by ELISA test and the anemia levels by micro-hematocrit. The presence of seropositivity was 90.8% (268/295) for the chicken anemia virus, 82.4% (244/295) for reovirus and 97% (286/295) for gumboro. Of the total, 9.6% (58/295) of the evaluated birds presented anemia, showing values of hematocrits between 20% and 27%. A positive correlation was found between chicken anemia virus and the other immunosuppressor viruses studied, gumboro (r=0.437; P<0.0001) and reovirus (r=0.312; P<0.0001). The obtained results in this research demonstrated the presence of viral anemia, in broilers, in the Zulia Region, with or without the presence of reovirus and/or gumboro. That could have an effect, in either sub-clinical or clinical forms.

A VP3/VP1 gene polymerase chain reaction assay for detection of chicken anemia virus in broiler samples

Desenvolveu-se uma reação em cadeia de polimerase (PCR) para amplificação do altamente conservado gene VP3 e da região 5 do gene VP1, para o diagnóstico do vírus da anemia das galinhas (CAV), diretamente em amostras de campo de órgãos de frangos de corte com suspeita clínica da doença. A comparação entre o PCR VP3/VP1 com isolamento viral in vivo indicou 100 de concordância dos resultados, com 13 amostras positivas e três negativas em ambos os testes. Órgãos de outros 24 lotes de frangos com lesões e história clínica compatível com CAV foram testados com o PCR VP3/VP1 e com um PCR de referência com primers conhecidos para o gene VP1. Dezenove amostras resultaram positivas e uma negativa em ambos os PCR e quatro foram positivas apenas no PCR VP3/VP1. Estes resultados indicam que o PCR VP3/VP1 é um teste de diagnóstico sensível e específico, aplicável como alternativa ao método caro e demorado de isolamento viral in vivo especialmente considerando-se amostras do CAV não adaptáveis a cultivos de células MSB-1.

Um protocolo de "nested-PCR" para detecção do vírus da anemia das galinhas / A nested-PCR protocol for detection of the chicken anemia virus

Este trabalho descreve o estabelecimento de um pro!tocolo de nested-PCR para a detecção do vírus da anemia das galinhas (CAV, chicken anemia virus), agente causador da anemia infecciosa das galinhas. Para a extração de DNA a partir de amostras clínicas um método baseado no uso de tiocianato de guanidina mostrou-se mais sensível e prático, do que os demais avaliados. Para a PCR inicial foi selecionado um par de primers que amplifica uma região de 664 pares de bases (pb) do gene VP1. Para a nested-PCR propriamente dita, foi selecionado um segundo par que amplifica uma região interna de 520 pb. A especificidade dos primers foi avaliada utilizando amostras de lotes controlados para CAV. Outras trinta amostras vírus e bactérias, causadoras de doenças em aves, não geraram produto de amplificação. A sensibilidade do teste foi determinada a partir de diluições seriadas de uma amostra vacinal de CAV. A nested-PCR mostrou ser mais sensível do que a PCR e foi capaz de detectar pelo menos 0,16 TCID50 por cento da cepa vacinal. Além disso, detectou DNA viral em tecidos, soro e cama aviária de lotes com e sem sinais clínicos. Conclui-se que, como técnica para a detecção do CAV, o protocolo de nested-PCR aqui descrito, é mais sensível, rápido e menos trabalhoso do que o isolamento viral em cultivo celular.

Prevalence of antibodies against chicken anaemia virus (CAV) in broiler breeders in Southern Brazil

A doença clínica causada pelo vírus da anemia das galinhas (CAV) ocorre quando os pintos são infectados durante as primeiras duas semanas de vida e pode ser prevenida se as matrizes transferirem anticorpos suficientes para a sua progênie. Em vista disso, este estudo foi realizado visando determinar a prevalência de anticorpos contra o CAV em alguns lotes de matrizes pesadas no Brasil. Buscou-se ainda verificar em que fase da vida as reprodutoras seriam infectadas e quais seriam os títulos de anticorpos nessas aves. Um total de 1709 amostras de soro de 64 lotes de reprodutoras não vacinadas e 12 lotes de reprodutoras vacinadas contra o CAV foram analisados por ELISA. Todos os lotes de aves não vacinadas apresentaram anticorpos. Dentre esses, 89 por cento dos indivíduos foram positivos, 52 por cento com títulos de anticorpos capazes de conferir proteção a sua progênie contra o CAV. Igualmente, todos os lotes de matrizes vacinadas apresentaram anticorpos contra o CAV em títulos considerados protetores para a progênie. Conclui-se que a vacinação das reprodutoras parece capaz de conferir proteção aos pintinhos contra doença associada ao CAV.

Cloning of chicken anemia virus vp3 gene and apoptosis inductive effect of vp3 gene in vitro / 华中科技大学学报（医学）（英德文版）

Using PCR technique, the vp3 gene of chicken anemia virus (CAV) was cloned into the eukaryotic expression vector pcDNA3 to construct a recombinant pcDNA-vp3. Restriction enzyme digestion and sequencing analysis revealed that CAV vp3 gene was correctly inserted into the blank vector pcDNA3. After LipofectAMINE-mediated transfection in vitro with pcDNA-vp3 and pcDNA3 respectively, the total mRNA was extracted from liver carcinoma cell lines HepG2 and diploid cell line L-02, and RT-PCR was performed afterward. The results of RT-PCR suggested that vp3 gene was expressed in these two cell lines. At the same time, using in situ apoptotic detection assay, TUNEL kits, the apoptotic cells were found in pcDNA-vp3 transfected HepG2, but not in mock transfected cell lines. VP3 could induce cell death by apoptosis in cancer cell lines, but not in diploid cell lines. All the results indicated that CAV vp3 gene, a potential therapeutic agents, has the potential of being used for cancer treatment.

Experimental study on the antitumor effect of chicken anemia virus vp3 gene against liver carcinoma in vivo / 华中科技大学学报（医学）（英德文版）

In order to testify the antitumor effect, especially its effect against liver carcinoma in vivo, of VP3 protein, one kind of protein coded by chicken anemia virus, recombinants pcDNA-vp3 containing chicken anemia virus vp3 gene, and control vector pcDNA3 were mixed with murine liver carcinoma cell lines H22 respectively. The mixture was injected subcutaneously into Balb/C mice. Some days later, the mice were killed and the solid tumor weighed. The antitumor efficiency was evaluated. The manners of VP3 protein in vivo inducing tumor cell death were identified by using TUNEL assay. All the results suggested that the injection of pcDNA-vp3 and H22 mixture resulted in a significant reduction of tumor growth in mice when compared with the results of control groups. TUNEL assay revealed that VP3 induced apoptosis in vivo. All these indicated that CAV vp3 might be a potential new gene in reducing the growth rate of tumor cells in liver carcinoma or in other kind of solid tumors in vivo.

Cloning of chicken anemia virus vp3 gene and apoptosis inductive effect of vp3 gene in vitro / 华中科技大学学报（医学）（英德文版）

Using PCR technique, the vp3 gene of chicken anemia virus (CAV) was cloned into the eukaryotic expression vector pcDNA3 to construct a recombinant pcDNA-vp3. Restriction enzyme digestion and sequencing analysis revealed that CAV vp3 gene was correctly inserted into the blank vector pcDNA3. After LipofectAMINE-mediated transfection in vitro with pcDNA-vp3 and pcDNA3 respectively, the total mRNA was extracted from liver carcinoma cell lines HepG2 and diploid cell line L-02, and RT-PCR was performed afterward. The results of RT-PCR suggested that vp3 gene was expressed in these two cell lines. At the same time, using in situ apoptotic detection assay, TUNEL kits, the apoptotic cells were found in pcDNA-vp3 transfected HepG2, but not in mock transfected cell lines. VP3 could induce cell death by apoptosis in cancer cell lines, but not in diploid cell lines. All the results indicated that CAV vp3 gene, a potential therapeutic agents, has the potential of being used for cancer treatment.