Fowl adenovirus Group I as a causal agent of inclusion body hepatitis/hydropericardium syndrome (IBH/HPS) outbreak in brazilian broiler flocks / Adenovirus aviário Ggrupo I como um agente causal da síndrome da hepatite por corpúsculo de inclusão/hidropericárdio (IBH/HPS) em lotes de frangos de corte

Commercial broiler flocks from a farm located in the State of São Paulo, Brazil, presented diarrhea, depression, increased mortality and poor weight gain. Upon post-mortem examination, classical signs of Inclusion Body Hepatitis/Hydropericardium Syndrome (IBH/HPS) were observed, including enlarged pale yellow-colored livers and straw-colored liquid in the pericardial sac. In addition, gross lesions were also observed in the kidneys, pancreas, thymus, intestines and gallbladder. Samples of these organs were analyzed by PCR for the detection of the hexon gene of the Fowl Adenovirus (FAdVs) Group I. The results were positive for both flocks (A and B) assayed by PCR. The macroscopic lesions associated with the detection of FAdV Group I by PCR in several of these affected organs allowed for the identification of IBH/HPS. In fact, this is the first report in Brazil of IBH/HPS in broilers, which identifies FAdVs group I as a causal agent of the disease. These findings may contribute to the worldwide epidemiology of the adenovirus-mediated hepatitis/hydropericardium syndrome...

Lotes comerciais de frangos de uma granja localizada no Estado de São Paulo, Brasil, apresentavam diarreia, depressão, aumento de mortalidade e baixo ganho de peso. Após o exame post-mortem, sinais clássicos da síndrome de hepatite por corpúsculo de inclusão/hidropericárdio (IBH/HPS) foram observados incluindo hepatomegalia com aspecto amarelado pálido e líquido de coloração amarelo palha no saco pericárdio. Além disso, as alterações macroscópicas foram também observadas nos rins, pâncreas, timo, intestinos e vesícula biliar. Amostras destes órgãos foram analisadas pela técnica de PCR para detectar o adenovírus aviário do grupo I através do gene Hexon. Os resultados foram positivos para ambos os lotes (A e B) utilizando-se a técnica de PCR. As lesões macroscópicas associadas à detecção do adenovírus aviário do grupo I pela técnica de PCR em vários destes órgãos acometidos permitiu a identificação da síndrome de hepatite/hidropericárdio em frangos no Brasil. Ao nosso conhecimento, este é a primeira descrição da síndrome de hepatite/hidropericárdio causado por adenovírus aviário do grupo I, no Brasil. Estes achados podem contribuir com a epidemiologia mundial do adenovírus mediando a síndrome de hepatite/hidropericárdio...

Development and validation of a genotype 3 recombinant protein-based immunoassay for hepatitis E virus serology in swine

Hepatitis E virus (HEV) is classified within the family Hepeviridae, genus Hepevirus. HEV genotype 3 (Gt3) infections are endemic in pigs in Western Europe and in North and South America and cause zoonotic infections in humans. Several serological assays to detect HEV antibodies in pigs have been developed, at first mainly based on HEV genotype 1 (Gt1) antigens. To develop a sensitive HEV Gt3 ELISA, a recombinant baculovirus expression product of HEV Gt3 open reading frame-2 was produced and coated onto polystyrene ELISA plates. After incubation of porcine sera, bound HEV antibodies were detected with anti-porcine anti-IgG and anti-IgM conjugates. For primary estimation of sensitivity and specificity of the assay, sets of sera were used from pigs experimentally infected with HEV Gt3. For further validation of the assay and to set the cutoff value, a batch of 1100 pig sera was used. All pig sera were tested using the developed HEV Gt3 assay and two other serologic assays based on HEV Gt1 antigens. Since there is no gold standard available for HEV antibody testing, further validation and a definite setting of the cutoff of the developed HEV Gt3 assay were performed using a statistical approach based on Bayes' theorem. The developed and validated HEV antibody assay showed effective detection of HEV-specific antibodies. This assay can contribute to an improved detection of HEV antibodies and enable more reliable estimates of the prevalence of HEV Gt3 in swine in different regions.

Viral hepatitis in patients infected with human immunodeficiency virus

From 1992 to 1995 we studied 232 (69 percent male, 87 percent Caucasian) anti-human immunodeficiency virus (anti-HIV) positive Brazilian patients, through a questionnaire; HIV had been acquired sexually by 50 percent, from blood by 32 percent, sexually and/or from blood by 16.4 percent and by an unknown route by 1.7 percent. Intravenous drug use was reported by 29 percent; it was the most important risk factor for HIV transmission. The alanine aminotransferase quotient (qALT) was >1 for 40 percent of the patients, 93.6 percent had anti-hepatitis A virus antibody, 5.3 percent presented hepatitis B surface antigen, 44 percent were anti-hepatitis B core antigen positive and 53.8 percent were anti-hepatitis C virus (anti-HCV) positive. The anti-HCV test showed a significant association with qALT>1. Patients for whom the probable HIV transmission route was blood had a 10.8 times greater risk of being anti-HCV positive than patients infected by other routes. Among 30 patients submitted to liver biopsy, 18 presented chronic hepatitis

The use of non-human primates as animal models for the study of hepatitis viruses

Hepatitis viruses belong to different families and have in common a striking hepatotropsin and restrictions for propagation in cell culture. The transmissibility of hepatitis is in great part limited to non-human primates. Enterically transmitted hepatitis viruses (hepatitis A virus and hepatitis E virus) can induce hepatitis in a number of OLD World and New Worls monkey species, while the host range of non-human primates susceptible to hepatitis viruses transmitted by the parenteral route (hepatitis B virus, hepatitis C virus and hepatitis delta virus) is restricted to few species of Old World monkeys, especially the chimpanzee. Experimental studies on non-human primates have provided an invaluable source of information regarding the biology and pathogenesis of these viruses, and represent a still indispensable tool for vaccine and drug testing.

Esquistossomose e hepatites virais: uma revisão / Schistosomiasis and viral hepatitides: a review

Os principais estudos sobre a associação esquistossomose e hepatite pelos vírus B, C e D são apresentados e discutidos. As limitações de cada estudo são apontadas e os autores sugerem novos caminhos na investigação desta provável interação.

The papers published on the association of schistosomiasis with viral hepatitis (B, C and D) are reviewed. The shortcomings of each work are pointed out and suggestions are forwarded to try and direct the investigations on this probable interaction.

Reduction of the accumulation of viral mRNA and of cellular rRNA synthesis in MHV3-infected macrophages of resistant mice

1. After MHV3 infection, only macrophages from resistant A/J mice partially restricted virus growth compared to those from susceptible BALB/c mice (2 logs of difference in virus titer). 2. Cellular ribosomal ribonucleic acid (rRNA) synthesis by MHV3-infected macrophages was decreased only in A/J mouse macrophages as indicated by accumulation of the 28S rRNA fraction. 3. The accumulation of viral messenger ribonucleic acids (mRNAs) in MHV3-infected macrophages was also reduced in A/J mouse macrophages compared to BALB/c mice. 4. In pulse-chase experiments of viral protein synthesis, the appearance, glycosylation and cleavage of glycoprotein S, as well as the metabolism of nucleoprotein N were delayed in A/J mouse macrophages. 5. These data show that MHV3 infection of A/J mouse macrophages induced an imbalanced accumulation of the 28S fraction of rRNA. Furthermore the synthesis of mRNAs correlated with viral protein synthesis in both A/J and BALB/c macrophages, but was delayed in A/J mice. 6. These results suggest that the partial restriction of MHV3 replication in macrophages of resistant A/J mice may take place during or before the mRNA synthesis, although it is correlated with the appearance, glycosylation, cleavage and metabolism of viral proteins

Mouse hepatitis virus 3 and interferon gamma binding to extracted macrophage proteins correlate with virus growth in A/J and BALB/c mice

1. After immunization, adult A/J mice are resistant and BALB/c mice are susceptible to MHV3 infection. After IFN gamma activation, only macrophages originating from A/J mice were able to partially restrict MHV3 growth. 2. When the binding of MHV3 and interferon (IFN) gamma to solubilized cytoplasmic and membrane macrophage proteins of mice was determined by ELISA, there was more binding of MHV3 to proteins extracted from BALB/c macrophages than to proteins extracted from A/J macrophages. When the proteins were obtained from IFN gamma-activated macrophages, decreased MHV3 binding was observed only in proteins originating from A/J macrophages. 3. ELISA showed a comparable binding of IFN gamma to A/J or BALB/c macrophage proteins. When the proteins were obtained from IFN gamma-activated macrophages, only IFN gamma-binding to A/J macrophage proteins was increased. 4. The results indicate a different expression and IFN gamma modulation of MHV3 receptors in macrophages from A/J and BALB/c mice, which directly correlated with their acquired resistance or susceptibility to MHV3 infection

Diagnóstico de hepatitis con cuerpos de inclusión mediante la prueba de inmunofluorescencia / Inclusion body hepatitis diagnosis by the immunofluorescence test

Se elaboró un conjugado para diagnóstico de hepatitis con cuerpos de inclusión (HCI). Para ello se utilizaron 60 pollos de engorda Arbor Acres, los cuales permanecieron en unidades de aislamiento durante 59 días. A partir de la 2a semana de edad, las aves fueron inmunizadas semanalmente con adenovirus tipo 1; se obtuvo un suero hiperinmune contra el virus utilizado. El suero obtenido permitió la elaboración de un conjugado contra adenovirus tipo 1. Se evaluó la especificidad del conjugado, usando como referencia 14 casos positivos a HCI diagnosticados por histopatología. Finalmente, se infectaron cultivos celulares de fibroblastos de embrión de pollo con adenovirus tipo I, luego se realizó en ellos la prueba de inmunofluorescencia, utilizando testigos negativos. Los resultados muestran que la técnica de inunofluorescencia es de gran confiabilidad para el diagnóstico de HCI.

A comparative study of resistance to MHV3 infection in genetically homogeneous and heterogeneous mouse populations

Resistance to MHV3 infection was investigated in genetically homogeneous inbred (A/J, BALB/c) and genetically selected (High, Low) mouse lines. The A/J and L lines are resistant and the BALB/c and H mice are susceptible. The genetic analysis was performed on the F1 hybrids, as well as on the genetically heterogeneous F2 populations and backcrosses bred from HxL and A/JxBALB/c lines. The mortality rates of the F1 hybrids showed codominance of susceptibility and resistance characters. The results indicate that the same MHV3 susceptibility genes are present in isogenic and selected lines and corroborate previous results showing that at least two major genes are involved in the control of this response

Vacunas experimentales contra hepatitis a cuerpo de inclusión aviar. I valoración serológica / Experimental vaccines against avian inclusion body hepatitis. I. Serological evaluation

Se elaboraron dos vacunas experimentales (Vac-19 y Vac-28) de Hepatitis a Cuerpo de Inclusión (HCI) a partir de los serotipos 4,10 y 11, aislados en brotes de campo en el país. Las cepas se atenuaron por pasajes en huevos embrionados SPF (16 y 22 pasajes para ambas vacunas) y cultivo de células renales (3 y 6 pasajes respectivamente). Se utilizaron cuatro grupos (G) experimentales: G I y G II formado por 8 pollos cada uno, vacunados vía oral (4,4 DICC55/ml) con Vac-19 y Vac-28 respectivamente a la tercera semana y revacunados a los 35 días por igual vía y dosis. Los grupos G III y G IV con 5 pollos cada uno correspondieron a control positivo y negativo, ambos grupos sin vacunar, el primero solo desafiado con un pool de los serotipos 4,10 y 11, a los 45 días de edad y el último sin desafiar. Exámenes clínicos serológicos se realizaron previo y posterior a las vacunaciones y desafío. La respuesta inmune se midió, a través de Inmunodifusión en Gelosa (IDG) y Seroneutralización (SN) en Cultivo de Células Renales (CCR) por el método ß (200 DICC50/50*l). Mediante la prueba IDG se observaron reacciones positivas (100%) desde el día 43 en adelante en los grupos cavunados y desde el 55 en el grupo desafiado (GIII). Los Títulos Medios Geométricos (TMG) previo al desafío fueron G I de 1.194 y en G II 23.525. Con posterioridad al desafío se observó un TMG de 7.760 y . 305.736 respectivamente en ambos grupos. El G III tuvo un TMG de 640. No se observó signología clínica y mortalidad el desarrollo de la experiencia. Se concluye que solo Vac-28 originó protección a las aves, emdida por la respuesta inmune humoral, pero por las lesiones observadas en el grupo solo vacunado se debería continuar estudiando sucompleta atenuación