Produção in vitro de embriões bovinos com sêmen congelado após prévia infecção com Herpesvirus bovino tipo 5 / In vitro production of bovine embryos with frozen semen previously infected with bovine Herpesvirus type 5 before sperm freezing

O Herpesvirus bovino tipo 5 (BoHV-5) tem sido recentemente descrito no sêmen contaminado. Apesar de ter sido identificado no sêmen bovino, sua influência na produção de embriões in vitro não foi ainda relatada. O presente estudo teve como objetivo verificar a susceptibilidade de oócitos bovinos maturados e fertilizados invitro, com sêmen congelado, infectado experimentalmente com BoHV-5, antes da congelação, avaliando-se o desenvolvimento embrionário subsequente e o possível carreamento do vírus para o embrião via espermatozoide. Ejaculados de touro foram misturados e divididos em dois grupos: Grupo I, sêmen não exposto ao vírus e, Grupo II, sêmen exposto ao vírus. A presença do BoHV-5 foi investigada através de PCR e teste de hibridização in situ (ISH). Os dados foram analisados através de Teste-t de Student com P< 0,05 considerado como significativo. O vírus foi detectado em embriões avaliados com 168 h pós-inseminação. Não houve diferença significativa entre os diferentes grupos de tratamento para as taxas de produção in vitro de embriões para os respectivos estágios de desenvolvimento. Assim, conclui-se que, o sêmen contaminado com o BoHV-5 pode infectar os oócitos durante a fertilização in vitro, com carreamento do vírus para os embriões, não afetando, porém, o seu desenvolvimento in vitro.(AU)

Bovine herpesvirus type 5 (BoHV-5) has been recently described from contaminated semen. Despite having been identified in bovine semen, its transmission through use of infected fresh semen, just before freezing, on the in vitro embryo production has not yet been reported so far. Thus, this study was carried out to investigate the susceptibility of matured bovine oocytes to BoHV-5 infection after using frozen semen previously exposed to the virus, and their ability to develop for advanced blastocyst stages following in vitro fertilization (IVF). Ejaculates from bulls were mixed and divided into two groups, as follows: Group 1, semen not exposed to the virus, and Group 2, infected sperm. The presence of BoHV-5 was investigated by PCR and in situ hybridization assays. Results were analyzed through use of Student t - test with P < 0.05 considered as significant. The virus was detected in blastocysts evaluated at 168 h post-insemination. There was no significant difference between groups for the in vitro embryo production at any developmental stage. Thus, it is concluded that semen infected with BoHV-5 can infect oocytes during IVF, with the virus transmission to embryos via sperm; however, embryonic development was not impaired, as evidenced by the subsequent blastocyst formation.(AU)

Produção in vitro de embriões bovinos com sêmen congelado após prévia infecção com Herpesvirus bovino tipo 5 / In vitro production of bovine embryos with frozen semen previously infected with bovine Herpesvirus type 5 before sperm freezing

O Herpesvirus bovino tipo 5 (BoHV-5) tem sido recentemente descrito no sêmen contaminado. Apesar de ter sido identificado no sêmen bovino, sua influência na produção de embriões in vitro não foi ainda relatada. O presente estudo teve como objetivo verificar a susceptibilidade de oócitos bovinos maturados e fertilizados invitro, com sêmen congelado, infectado experimentalmente com BoHV-5, antes da congelação, avaliando-se o desenvolvimento embrionário subsequente e o possível carreamento do vírus para o embrião via espermatozoide. Ejaculados de touro foram misturados e divididos em dois grupos: Grupo I, sêmen não exposto ao vírus e, Grupo II, sêmen exposto ao vírus. A presença do BoHV-5 foi investigada através de PCR e teste de hibridização in situ (ISH). Os dados foram analisados através de Teste-t de Student com P< 0,05 considerado como significativo. O vírus foi detectado em embriões avaliados com 168 h pós-inseminação. Não houve diferença significativa entre os diferentes grupos de tratamento para as taxas de produção in vitro de embriões para os respectivos estágios de desenvolvimento. Assim, conclui-se que, o sêmen contaminado com o BoHV-5 pode infectar os oócitos durante a fertilização in vitro, com carreamento do vírus para os embriões, não afetando, porém, o seu desenvolvimento in vitro.

Bovine herpesvirus type 5 (BoHV-5) has been recently described from contaminated semen. Despite having been identified in bovine semen, its transmission through use of infected fresh semen, just before freezing, on the in vitro embryo production has not yet been reported so far. Thus, this study was carried out to investigate the susceptibility of matured bovine oocytes to BoHV-5 infection after using frozen semen previously exposed to the virus, and their ability to develop for advanced blastocyst stages following in vitro fertilization (IVF). Ejaculates from bulls were mixed and divided into two groups, as follows: Group 1, semen not exposed to the virus, and Group 2, infected sperm. The presence of BoHV-5 was investigated by PCR and in situ hybridization assays. Results were analyzed through use of Student t - test with P < 0.05 considered as significant. The virus was detected in blastocysts evaluated at 168 h post-insemination. There was no significant difference between groups for the in vitro embryo production at any developmental stage. Thus, it is concluded that semen infected with BoHV-5 can infect oocytes during IVF, with the virus transmission to embryos via sperm; however, embryonic development was not impaired, as evidenced by the subsequent blastocyst formation.

Poult Intestinal Organ Culture for Propagation of Turkey Coronavirus and Assessment of Host-virus Interactions

Infection of young poults with turkey coronavirus (TCoV) produces a syndrome characterized by acute enteritis, diarrhea, anorexia, ruffled feathers, decreased body weight gain and uneven flock growth. The objective of this study was to standardize an intestinal organ culture (IOC) in order to assess host-virus interaction related to apoptosis. For this purpose the Brazilian strain (TCoV/Brazil/2006 with GenBank accession number FJ188401), was used for infection. Infected IOC cells had mitochondrial dysfunction and initial nuclear activation with MTT value of 90.7 (± 2.4) and apoptotic factor 2.21 (± 2.1), considered statistically different from uninfected IOC cells (p > 0.05). The kinetics of TCoV antigens and viral RNA was directly correlated to annexin-V, caspases- 2 and -3, p53, BCl-2 antigens at 24, 72 and 96 h post-infection (p.i.). Morphological and biochemical features of apoptosis, such as in situ nuclear fragmentation (TUNEL and annexin-V) and DNA ladder formation were also detected in infected cells at all assayed p.i. intervals. Moreover, different from other coronaviruses, the expression of both effective caspase-2 and -3 and p53 antigens were considered lower. However, at all p.i., the BCl-2 antigens were expressed quantitatively and qualitatively as viral antigen measured by immunofluorescence microscopy analysis. Because the diagnosis of TCoV infection is only performed by infecting embryonated poult eggs, the pathological characteristics related to host-virus interaction remain unclear. This is the first report on apoptosis of TCoV infected IOC, and reveals that it may be useful immunological method to assess virus pathogenesis.(AU)

Canine Transmissible Venereal Tumors: Aspects Related to Programmed Cell Death

Canine transmissible venereal tumor (CTVT) is a neoplasm transmitted by the physical transfer of viable tumor cells by direct contact with injured skin and/or mucous tissue. These cells can transpose across histocompatibility barriers into unrelated hosts. This review focuses on the biology of apoptosis and the interaction of proteins involved in this process, as well as p53, p63 and the antiapoptotic protein Bcl-2. As such, this disease offer unique opportunity to study the biology of transplantable tumours and the interaction of proteins involved in apoptosis process and the prognosis of CTVT.(AU)

Pathological and Molecular Analysis of Turkey Coronavirus Replication in Captive Wild Turkey Embryos (Broad-Breasted Bronze Breeder)

The degree of genetic and pathologic variation exhibited by a turkey Coronavirus (TCoV) strain was investigated after nine serial passages in 25-day-old turkey embryos obtained from wild broad-breasted bronze breeders. In spite of spleen, liver, kidneys, cloacal bursa and thymus have been collected and analysed, the main histopathological changes were only documented in the intestine sections. Microscopic lesions were characterized as mild enteritis, low degree of enterocyte vacuolization and detachment of the intestinal villous after five consecutive passages and were considered absent in the last passages. Genealogic analysis based on S1 and S2 DNA sequences suggested that Brazilian isolate might be considered as originated from TCoV strains circulating in the United States, as 100% identity with TCoV-Gl strain. Although S1 S2 sequences from each passage revealed no significant point mutations, and no correlation could be speculate between S2 nucleotide changes and pathologic features in infected embryos. This is the first demonstration of wild turkey embryos as a model for TCoV isolation and propagation.(AU)

Expression of pro-and-anti-apoptotic antigens in the cerebellum of dogs naturally infected with canine distemper virus

Canine distemper virus (CDV) may induce multifocal demyelination in the central nervous system of infected dogs. The present work investigated apoptosis in white and gray matter (granular layer) in the cerebellum of naturally infected dogs by the analysis of the expression of the pro-apoptotic antigens caspase 2 and 3 , b(terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL-staining) positivity, annexin-V immunodetection, and the presence of the anti-apoptotic antigens, BCl-2 and p53. Cerebellum specimens were obtained from the Laboratory of Animal Pathology, from 1995 to 2009, and the 5-µm thick fragments were stained both with hematoxylin-eosin and Shorr. All samples were diagnosed as positive for CDV genome by reverse transcriptase polymerase chain reaction targeting the nucleocapsid gene. The anti-apoptotic pathways evidenced in this study were BCl-2 and p53 proteins that were intensively detected in cerebellum of CDV positive slides (40-80% of labeled cells/mm2). In addition, the apoptosis markers annexin-V and TUNEL are directly correlated among the same samples (80 and 40% of labeled cells, respectively). This is the first description of p53 and annexin-V expression, characterized as anti-apoptotic and apoptotic proteins, involvement in canine natural cases of CDV infections. (AU)

Expression of pro-and-anti-apoptotic antigens in the cerebellum of dogs naturally infected with canine distemper virus

Canine distemper virus (CDV) may induce multifocal demyelination in the central nervous system of infected dogs. The present work investigated apoptosis in white and gray matter (granular layer) in the cerebellum of naturally infected dogs by the analysis of the expression of the pro-apoptotic antigens caspase – 2 and – 3 , b(terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL-staining) positivity, annexin-V immunodetection, and the presence of the anti-apoptotic antigens, BCl-2 and p53. Cerebellum specimens were obtained from the Laboratory of Animal Pathology, from 1995 to 2009, and the 5-µm thick fragments were stained both with hematoxylin-eosin and Shorr. All samples were diagnosed as positive for CDV genome by reverse transcriptase polymerase chain reaction targeting the nucleocapsid gene. The anti-apoptotic pathways evidenced in this study were BCl-2 and p53 proteins that were intensively detected in cerebellum of CDV positive slides (40-80% of labeled cells/mm2). In addition, the apoptosis markers annexin-V and TUNEL are directly correlated among the same samples (80 and 40% of labeled cells, respectively). This is the first description of p53 and annexin-V expression, characterized as anti-apoptotic and apoptotic proteins, involvement in canine natural cases of CDV infections.

Astrocyte intermediate filaments are important markers in olfactory bulb of bovine Herpesvirus type 5 natural infections

Astroglial cells are the most abundant cells in the mammalian central nervous system, yet our knowledge about their function in bovine Herpesvirus type 5 (BoHV-5) has been limited. The aim of this study was to detect by immunohistochemistry assay the reactive astrocytes for glial fibrilary acidic protein (GFAP) and vimentin (VIM), considered intermediate filaments of the cytoskeleton, localized in olfactory bulb from natural acute cases of BoHV-5 infection. All samples were submitted to virus isolation, real-time polymerase chain reaction (RT-PCR) and in situ hybridization (ISH) technique to confirm the virus transcription and respective genome. Samples were classified into four groups according to the severity of histological lesions. Groups III and IV, which histological lesions were classified as alacia, gliosis, satellitosis, neuronophagia and neuronal necrosis, 35% (± 1.8-2.1) of the inflammatory mononuclear cells, corresponded to CD3 positive lymphocytes. In the same group, 35% (± 1.8) of astrocytes were described as reactive to GFAP and VIM proteins. An agreement of r = 1.0 (P<0.0001) was found between histological lesions, intermediate filaments expression, viral DNA and transcription and CD3 lymphocytes. However, samples with mild histological lesions, 10.8 to 14.2% of astrocytes were classified as reactive to GFAP and VIM filaments. Our findings suggest that GFAP and VIM reactive astrocytes, in primary site of virus replication, seems to play an important role in neurovirulence, in spite of many questions concerning the virus immunopathology remains unclear

Astrocyte intermediate filaments are important markers in olfactory bulb of bovine Herpesvirus type 5 natural infections

Astroglial cells are the most abundant cells in the mammalian central nervous system, yet our knowledge about their function in bovine Herpesvirus type 5 (BoHV-5) has been limited. The aim of this study was to detect by immunohistochemistry assay the reactive astrocytes for glial fibrilary acidic protein (GFAP) and vimentin (VIM), considered intermediate filaments of the cytoskeleton, localized in olfactory bulb from natural acute cases of BoHV-5 infection. All samples were submitted to virus isolation, real-time polymerase chain reaction (RT-PCR) and in situ hybridization (ISH) technique to confirm the virus transcription and respective genome. Samples were classified into four groups according to the severity of histological lesions. Groups III and IV, which histological lesions were classified as alacia, gliosis, satellitosis, neuronophagia and neuronal necrosis, 35% (± 1.8-2.1) of the inflammatory mononuclear cells, corresponded to CD3 positive lymphocytes. In the same group, 35% (± 1.8) of astrocytes were described as reactive to GFAP and VIM proteins. An agreement of r = 1.0 (P<0.0001) was found between histological lesions, intermediate filaments expression, viral DNA and transcription and CD3 lymphocytes. However, samples with mild histological lesions, 10.8 to 14.2% of astrocytes were classified as reactive to GFAP and VIM filaments. Our findings suggest that GFAP and VIM reactive astrocytes, in primary site of virus replication, seems to play an important role in neurovirulence, in spite of many questions concerning the virus immunopathology remains unclear(AU)

Apoptosis detection in embryonic chicken lymphoid tissues infected with attenuated very virulent infectious bursal disease virus (vvIBDV)

We exposed chicken embryos at embryonating day (ED18) to a cell-adapted very virulent strain of IBDV (ca-vvIBDV) and original vvIBDV and examined the apoptosis from infected bursa of Fabricius (BF) and thymus organs. Following ca-vvIBDV exposure, embryonic bursa showed mild cellular destruction, lower rate of apoptosis and presence of viral proteins detectable by immunohistochemistry. In contrary, original vvIBDV exposed embryos had an enhanced detectable changes in the bursa associated to an increase apoptotic events, and most of the times, total destruction of BF follicles. In thymus, viral antigen was detectable until after hatch. Positives cell signals to activated caspase-3 were intensively detect in embryos lymphoid tissues exposed to original vvIBDV observed in BF and less in thymus. No immunoreactive thymocytes were visualized in embryos exposed to ca-vvIBDV. Apoptosis changes, such as chromatin condensation, DNA fragmentation, and the appearance of apoptotic nuclear bodies, were observed in both organs. TUNEL-detected DNA was more intense in original vvIBDV infected lymphoid cells, and less apoptotic cells were detectable in attenuated strain. By sequencing analysis, e attenuation presented amino acid changes at position 222 (A→→P), 256 (I→V) and 279 (D→N). One serine in the serine-rich heptapeptide (position 333) was substituted into other amino acid which is similar to the IBDV vaccine strain. Taken together our results indicate that virus attenuation interferes with caspase-3 apoptotic pathway and may play an important role in switch viral pathogenesis.