RESUMO
The aim of this work was to study the interstitial aggregates of immune cells observed in pulmonary parenchyma of calves preinfected with bovine viral diarrhea virus and challenged later with bovine herpesvirus 1. In addition, the intent of this research was to clarify the role of bovine viral diarrhea virus in local cell-mediated immunity and potentially in predisposing animals to bovine respiratory disease complex. Twelve Friesian calves, aged 8 to 9 months, were inoculated with noncytopathic bovine viral diarrhea virus genotype 1. Ten were subsequently challenged with bovine herpesvirus 1 and euthanized at 1, 2, 4, 7, or 14 days postinoculation. The other 2 calves were euthanized prior to the second inoculation. Another cohort of 10 calves was inoculated only with bovine herpesvirus 1 and then were euthanized at the same time points. Two calves were not inoculated with any agent and were used as negative controls. Pulmonary lesions were evaluated in all animals, while quantitative and biosynthetic changes in immune cells were concurrently examined immunohistochemically to compare coinfected calves and calves challenged only with bovine herpesvirus 1. Calves preinfected with bovine viral diarrhea virus demonstrated moderate respiratory clinical signs and histopathologic evidence of interstitial pneumonia with aggregates of mononuclear cells, which predominated at 4 days postinoculation. Furthermore, this group of animals was noted to have a suppression of interleukin-10 and associated alterations in the Th1-driven cytokine response in the lungs, as well as inhibition of the response of CD8+ and CD4+ T lymphocytes against bovine herpesvirus 1. These findings suggest that bovine viral diarrhea virus preinfection could affect the regulation of the immune response as modulated by regulatory T cells, as well as impair local cell-mediated immunity to secondary respiratory pathogens.
Assuntos
Anticorpos Antivirais/imunologia , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Vírus da Diarreia Viral Bovina Tipo 1/imunologia , Herpesvirus Bovino 1/imunologia , Imunidade Celular , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/patologia , Bovinos , Imuno-Histoquímica/veterinária , Interleucina-10/imunologia , Pulmão/imunologia , Pulmão/patologia , Linfócitos/imunologiaRESUMO
Dendritic cells (DCs) are "professional" antigen-presenting cells with a critical role in the regulation of innate and adaptive immune responses and thus have been considered of great interest in the study of a variety of infectious diseases. The objective of this investigation was to characterize the in vivo distribution of DCs in bovine tissues by using potential DC markers to establish a basis for the study of DCs in diseased tissues. Markers evaluated included MHCII, CD208, CD1b, CD205, CNA.42, and S100 protein, the latter 2 being expressed by follicular dendritic cells whose origin and role are different from the rest of hematopoietic DCs. Paraffin wax-embedded tissues from 6 healthy Friesian calves were subjected to the avidin-biotin-peroxidase method, and the most appropriate fixatives, dilutions, and antigen retrieval pretreatments were studied for each of the primary antibodies. The most significant results included the localization of CD208-positive cells not only in the T zone of lymphoid organs but also within lymphoid follicles; CD1b-positive cells were mainly found in thymus and interfollicular areas of some lymph nodes; cells stained with anti-CD205 antibody were scarce, and their location was mainly in nonlymphoid tissues; and CNA.42- and S100 protein-positive cells localized in primary lymphoid follicles and light zones of germinal centers, although showing differences in the staining pattern. Furthermore, MHCII was established as one of the most sensitive markers for any DC of hematopoietic origin. These results increase our understanding of DC immunolabeling and will help in future DC studies of both healthy and diseased tissues.
Assuntos
Doenças dos Bovinos/metabolismo , Células Dendríticas/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Antígenos CD/metabolismo , Biomarcadores/metabolismo , Bovinos , Doenças dos Bovinos/patologia , Células Dendríticas Foliculares/metabolismo , Sistema Digestório/metabolismo , Genes MHC da Classe II , Imuno-Histoquímica/veterinária , Tegumento Comum , Tecido Linfoide/metabolismo , Proteína 3 de Membrana Associada ao Lisossomo/imunologia , Proteína 3 de Membrana Associada ao Lisossomo/isolamento & purificação , Masculino , Sistema Respiratório/metabolismo , Proteínas S100/imunologia , Proteínas S100/metabolismoRESUMO
Survival in multiple myeloma has improved significantly in recent years, especially in young patients. We reviewed the evolution of the survival of patients with MM in three groups based on age at MM diagnosis over three time periods between 1999 and 2020 at our 12 de Octubre Hospital institution (H12O). Then, to confirm our results, we used data from TriNetx, a global health research platform that includes patients from Europe to US. Finally, we analysed differences in the patterns of treatment between networks across the world. KaplanâMeier analysis was used to estimate survival probabilities, and between-group differences were tested using the log-rank test and hazard ratio. For patients from H12O, the median OS was 35.61, 55.59 and 68.67 months for the 1999-2009, 2010-2014 and 2015-2020 cohorts, respectively (p = 0.0001). Among all patients included in the EMEA network, the median OS was 20.32 months versus 34.75 months from 1999-2009 versus 2010-2014. The median OS from the 2010-2014 versus 2015-2020 time cohorts was 34.75 months versus 54.43 months, respectively. In relation to the US cohort, the median OS from before 2010 versus 2010-2014 was not reached in either time cohort and neither when comparing the 2010-2014 versus 2015-2019 time cohorts. Bortezomib is the most commonly used drug in the EMEA cohort, while lenalidomide is the most commonly used drug in the US cohort. This large-scale study based on real-world data confirms the previous finding that MM patients have increased their survival in the last two decades.
Assuntos
Mieloma Múltiplo , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bortezomib/uso terapêutico , Dexametasona/uso terapêutico , Europa (Continente)/epidemiologia , Lenalidomida/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/diagnósticoRESUMO
INTRODUCTION: There is no agreement on the existence of the weekend effect in healthcare or, if it exists, on its possible causes. The objective of the study was to evaluate the differences in healthcare outcomes between patients admitted on weekdays or weekends in a high-complexity hospital. METHODS: Observational and retrospective study of patients admitted between 2016 and 2019 in a public hospital with more than 1300 beds. Hospitalization episodes were classified according to whether admission took place between Friday at 3:00 p.m. and the following Monday at 8:00 a.m. (weekend admission) or not (admission on weekdays). Mortality, length of stay and associated costs were compared, applying their respective risk-adjustment models. RESULTS: Of the total 169,495 hospitalization episodes analyzed, 48,201 (28.44%) corresponded to the weekend, presenting an older age (54.9 years vs. 53.9; P<.001), a higher crude mortality rate (5.22% vs. 4.59%; P<0.001), and a longer average length of stay (7.42 days vs. 6.74; P<.001), than those admitted on weekdays. The median crude cost of stay was lower (731.25 vs. 850.88; P<0.001). No significant differences were found when applying the adjustment models, with a risk-adjusted mortality ratio of 1.03 (0.99-1.08) vs. 0.98 (0.95-1.01), risk-adjusted length of stay of 1.002 (0.98-1.005) vs. 0.999 (0.997-1.002) and risk-adjusted cost of stay of 0.928 (0.865-0.994) vs. 0.901 (0.843-0.962). CONCLUSION: The results of the study reveal that the assistance provided during the weekends does not imply worse health outcomes or increased costs. Comparing the impact between hospitals will require a future homogenization of temporal criteria and risk adjustment models.
Assuntos
Hospitalização , Admissão do Paciente , Humanos , Mortalidade Hospitalar , Tempo de Internação , Estudos RetrospectivosRESUMO
The cross-reactivity of antibodies against human tumour necrosis factor (TNF)alpha, interleukin (IL)-1alpha, IL-1beta and porcine IL-6, and the distribution of immunolabelled cells were evaluated on paraffin wax-embedded tissues from five healthy calves. The tissues were fixed in 10% buffered formalin or Bouin's solution and processed for structural studies and immunohistochemical studies by the avidin-biotin-peroxidase technique. Bouin's solution proved to be the more suitable fixative and Tween 20 the most effective antigen unmasking technique for increasing detectable antigenicity. Constitutive expression of TNFalpha, IL-1alpha, IL-1beta and IL-6 by different cell populations, mainly macrophage-like cells, was detected. Lymphoid organs displayed a higher presence of immunolabelled cells than did lung, liver or kidney. TNFalpha and IL-1alpha appeared as the predominant cytokines, especially in the gut-associated lymphoid tissue of the ileum and in the regional mesenteric lymph nodes. The results will facilitate investigation of the role of these cytokine-producing cells in inflammatory disease processes in calves.
Assuntos
Anticorpos Monoclonais , Bovinos , Citocinas/biossíntese , Imuno-Histoquímica/veterinária , Inclusão em Parafina/veterinária , Animais , Reações Cruzadas , Feminino , Humanos , MasculinoRESUMO
Pigs inoculated with the Alfort 187 isolate of classical swine fever (CSF) virus were used to study the immunological mechanisms associated with the humoral immune response in the disease. Quantitative and qualitative changes in the B-cell population (lambda light chain [C-lambda]-positive, immunoglobulins [Ig]-M-positive, and IgG-positive were demonstrated in the spleen, thymus and ileocaecal lymph node. Blood and serum samples were used to examine changes in leucocytes, albumin/globulin ratios and specific antibodies against CSF virus titration. Despite the lymphoid depletion shown by infected animals, an increase in B cells and potentially immunoglobulin-producing C-lambda+ plasma cells was observed in the lymphoid organs from the onset of disease. The increase in C-lambda+ B cells was matched by a parallel increase in IgM+ cells, which attained peak values from 7 days post-inoculation (dpi), while IgG+ cells increased from 11 dpi onwards. The enhanced biosynthetic capacity of these cells may have been linked to the initiation of a humoral response to CSF virus, and to the progressive decline in the albumin/globulin ratios of inoculated animals. Activation, proliferation and differentiation of B cells coincided with the presence of viral antigen, and with an intense phagocytic and biosynthetic activity of monocytes-macrophages and T lymphocytes. The previously reported increase of cytokine (TNFalpha, IL-1alpha and IL-6) production by monocytes-macrophages, and the release of IL-2, IL-4 and IFNgamma by T lymphocytes, may play a role in the initiation of the humoral immune response in CSF. These changes may have influenced the late appearance of virus-specific antibodies in the study, as well as the progressive increase of immunoglobulins.
Assuntos
Linfócitos B/imunologia , Vírus da Febre Suína Clássica/patogenicidade , Peste Suína Clássica/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Linfócitos B/metabolismo , Linfócitos B/virologia , Peste Suína Clássica/sangue , Peste Suína Clássica/virologia , Vírus da Febre Suína Clássica/genética , Vírus da Febre Suína Clássica/isolamento & purificação , Feminino , Imuno-Histoquímica/veterinária , Tecido Linfoide/imunologia , Tecido Linfoide/patologia , Masculino , Sus scrofaRESUMO
Fourteen pigs were inoculated with the 'Alfort 187' strain of classical swine fever (CSF) virus and killed in pairs at 2, 4, 7, 9, 11, 14 or 17 days post-inoculation for histopathological, ultrastructural and immunohistochemical examination. For the latter method, the antibodies used were those against viral antigen Gp55, porcine myeloid marker SWC3, IL-1alpha, IL-6, TNF-alpha and Factor VIII-related antigen. Activation and increase in the number of hepatic macrophages was observed following viral detection in liver, as well as an increase in IL-1alpha and IL-6 production, mainly by Kupffer cells. Maximum detection of viral antigen was observed in the middle stage of the experiment coinciding with overexpression of the three cytokines studied, with IL-6 production by interstitial macrophages prominent at the end. Additionally, the labelling of platelets for Factor VIII-related antigen and the ultrastructural study of the sinusoids revealed activation and aggregation of thrombocytes close to Kupffer cells at the beginning of the infection. The liver seems to play a prominent role in the origin of the thrombocytopenia that occurs in CSF and contributes to the overexpression of proinflammatory cytokines considered responsible for the disorders observed during the course of the disease.
Assuntos
Peste Suína Clássica/imunologia , Citocinas/biossíntese , Células de Kupffer/imunologia , Fígado/imunologia , Fígado/virologia , Animais , Peste Suína Clássica/patologia , Vírus da Febre Suína Clássica , Feminino , Imuno-Histoquímica , Células de Kupffer/metabolismo , Células de Kupffer/ultraestrutura , Fígado/ultraestrutura , Ativação de Macrófagos/imunologia , Masculino , Microscopia Eletrônica de Transmissão , SuínosRESUMO
Protective immunity in sheep with bluetongue virus (BTV) infection as well as the role of BTV-induced cytokines during immune response remains unclear. Understanding the basis immunological mechanisms in sheep experimentally infected with serotypes 1 and 8 (BTV-1 and -8) was the aim of this study. A time-course study was carried out in order to evaluate cell-mediated immune response and serum concentrations of cytokines (IL-1ß, TNFα, IL-12, IFNγ, IL-4 and IL-10) with inflammatory and immunological functions. Depletion of T cell subsets (mainly CD4(+), γδ and CD25(+)) together with the absence of cytokines (IFNγ and IL-12) involved in the regulation of cell-mediated antiviral immunity at the first stage of the disease suggested that both BTV-1 and BTV-8 might impair host's capability against primary infections which would favor viral replication and spreading. However, cellular immune response and cytokines elicited an immune response in sheep that efficiently reduced viremia in the final stage of the experiment. Recovery of T cell subsets (CD4(+) and CD25(+)) together with a significant increase of CD8(+) T lymphocytes in both infected groups were observed in parallel with the decrease of viremia. Additionally, the recovery of CD4(+) T lymphocytes together with the significant increase of IL-4 serum levels at the final stage of the experiment might contribute to humoral immune response activation and neutralizing antibodies production against BTV previously described in the course of this experiment. These results suggested that both cellular and humoral immune response may contribute to protective immunity against BTV-1 and BTV-8 in sheep. The possible role played by IL-10 and CD25(+) cells in controlling inflammatory and immune response in the final stage of the experiment has also been suggested.
Assuntos
Vírus Bluetongue/imunologia , Bluetongue/imunologia , Bluetongue/virologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Carneiro Doméstico/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Citocinas/imunologia , Interleucina-10/imunologia , Interleucina-12/imunologia , Interleucina-1beta/imunologia , Interleucina-4/imunologia , Ovinos , Fator de Necrose Tumoral alfa/imunologia , Viremia/imunologiaRESUMO
The effects in vitro of both teicoplanin and vancomycin of blood peripheral human neutrophils have been studied by assays of antibiotic uptake and intracellular killing of previously phagocytosed Staphylococcus aureus. The effects of vancomycin and teicoplanin (a novel glycopeptide antibiotic), at the therapeutic concentrations reached in plasma (10, 25, 50, 75 and 100 mg/l) and at different times of incubation (5, 15, 30 and 60 min) were studied. The results indicate that: (1) the bactericidal effect of neutrophils increases with incubation time, (2) in the presence of both teicoplanin and vancomycin, the number of CFU/ml of intraphagocytic S. aureus declines with both increasing incubation time and exposure dose of the antibiotics and (3) at 100 mg/l of teicoplanin there is a significant increase in the percentage inhibition of S. aureus growth at all the times studied.
Assuntos
Neutrófilos/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Teicoplanina/farmacologia , Vancomicina/farmacologia , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Humanos , Neutrófilos/microbiologia , Fagocitose/efeitos dos fármacos , Fatores de TempoRESUMO
The present study was undertaken to determine whether teicoplanin and vancomycin influence the hemolytic and bactericidal activity of serum obtained from mice (Swiss, aged 15 +/- 2 weeks). Haemolytic activity was measured in CH-50 units (which represents the capacity of serum complement to lyse 50% of sheep red blood cells in the presence of specific antibody) and the bactericidal activity was estimated from the number of colony-forming units (CFU/ml) of Staphylococcus aureus that survived after 24 h of incubation in the presence of serum. The results indicate that (1) teicoplanin and vancomycin increase the haemolytic activity of serum; (2) in the serum from animals treated with both teicoplanin or vancomycin, the number of CFU/ml of Staphylococcus aureus declines; and (3) these antibiotics appear to have a similar effect upon the complement system.
Assuntos
Antibacterianos/farmacologia , Ativação do Complemento/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Teicoplanina/farmacologia , Vancomicina/farmacologia , Animais , Atividade Bactericida do Sangue/efeitos dos fármacos , Ativação do Complemento/imunologia , Via Alternativa do Complemento/efeitos dos fármacos , Via Clássica do Complemento/efeitos dos fármacos , Hemólise , Masculino , Camundongos , Staphylococcus aureus/imunologiaRESUMO
Cigarette smoking is known to alter the numerical presence and function of alveolar macrophages. It has been speculated that these cigarette-smoke-induced alterations contribute to the depressed pulmonary defence mechanism commonly demonstrated in smokers. Studies of the phagocytic and bactericidal activities of alveolar macrophages from smokers and non-smokers have yielded conflicting results. The purpose of this study was to investigate the phagocytic capacity of alveolar macrophages from mice exposed to cigarette smoke in relation to the ability to ingest inert particles (latex beads). Measurements were made before (basal values), immediately after, and 1, 12 or 24 h after exposure. Significant decreases were observed in the number of latex beads ingested by 100 macrophages (phagocytic index) and in the phagocytic efficiency for ingesting latex (mean number of latex beads ingested per activated macrophages) immediately after and 1 h after exposure, and in the number of activated macrophages (those with phagocytic activity) immediately after exposure.
Assuntos
Macrófagos Alveolares/fisiologia , Fagocitose/fisiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Animais , Contagem de Células , Látex , Masculino , Camundongos , MicroesferasRESUMO
The aim of this study was to determine the expression of three proinflammatory cytokines by pulmonary macrophages of sheep in paraffin wax-embedded tissue. Samples of lung from seven healthy sheep were fixed by immersion in either 10% neutral buffered formalin, acetic formalin, paraformaldehyde-lysine-periodate or Bouin's solution and processed for structural and immunohistochemical studies. The expression of interleukin (IL)-1alpha, IL-6 and tumour necrosis factor (TNF)-alpha by pulmonary intravascular macrophages (PIMs) and alveolar macrophages (AMs) was detected by the avidin-biotin-peroxidase (ABC) technique. Bouin's solution proved to be the most suitable fixative and Tween 20 the most effective pretreatment for increasing permeability. Constitutive expression of IL-1alpha, IL-6 and TNF-alpha by both macrophage populations was detected. The number of PIMs expressing IL-1alpha (the predominant cytokine in ovine lung) was higher than that of AMs, while the expression of IL-6 was greater in AMs. No differences between PIMS and AMs were found in respect of TNF-alpha expression. The evaluation of cytokine expression represents a valuable tool for studying the pathogenesis of disease in the ovine lung.
Assuntos
Citocinas/imunologia , Técnicas Imunoenzimáticas/veterinária , Macrófagos Alveolares/imunologia , Ovinos/fisiologia , Animais , Permeabilidade da Membrana Celular/efeitos dos fármacos , Fixadores , Interleucina-1/imunologia , Interleucina-6/imunologia , Macrófagos Alveolares/citologia , Macrófagos Alveolares/efeitos dos fármacos , Polissorbatos/farmacologia , Fixação de Tecidos/veterinária , Fator de Necrose Tumoral alfa/imunologiaRESUMO
Acute infections with bovine viral diarrhoea virus (BVDV), a major pathogen of cattle, are often asymptomatic or produce only mild clinical symptoms. However, they may play an important role in the bovine respiratory disease complex by exerting a marked immunosuppressive effect, as a result of the death of the immunocompetent cell populations involved in controlling innate and adaptive immune responses, together with a marked reduction of both cytokine expression and co-stimulatory molecule synthesis. Although experimental research and field studies have shown that acute BVDV infection enhances susceptibility to secondary infection, the precise mechanism involved in BVDV-induced immunosuppression remains unclear. The present study is aimed at measuring a range of blood parameters in a single group of fourteen calves infected with non-cytopathic BVDV-1. Focus has been put on those related to the cell-mediated immune response just as leucocyte populations and lymphocyte subpopulations, serum concentrations of cytokines (IL-1ß, TNF-α, IFN-γ, IL-12, IL-4 and IL-10) and acute phase proteins [haptoglobin, serum amyloid A (SAA), fibrinogen and albumin], as well as BVDV-specific antibodies and viremia. After non-cytopathic BVDV-1 infection, clinical signs intensity was never more than moderate coinciding with the presence of viremia and leucocyte and lymphocyte depletion. An early increase in TNF-α, IFN-γ and IL-12 levels in contrast to IL-1ß was observed in line with a raise in haptoglobin and SAA levels on the latest days of the study. As regards IL-4 levels, no evidence was found of any changes. However, a slight increase in IL-10 was observed, matching up the TNF-α decline during the acute phase response. These findings would help to increase our knowledge of the immune mechanisms involved in acute infection with non-cytopathic BVDV-1 strains, suggesting the existence of a clear tendency towards a type 1 immune response, thereby enhancing resistance against viral infections.
Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/imunologia , Vírus da Diarreia Viral Bovina Tipo 1/imunologia , Imunidade Celular , Reação de Fase Aguda/veterinária , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/sangue , Bovinos , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Interleucinas/sangue , Masculino , EspanhaRESUMO
Bovine viral diarrhea virus (BVDV) and bovine herpesvirus-1 (BHV-1) are important cattle pathogens that induce a broad immunosuppression on cell-mediated immune response on its own participating in the bovine respiratory disease complex (BRDC). The aim of our study was to evaluate the quantitative changes in immunocompetent cells in healthy calves and calves with subclinical bovine viral diarrhea (BVD), both inoculated with BHV-1. Total leukocyte counts exhibited changes mainly in neutrophils and lymphocytes that can contribute to the BVDV immunosuppression, thus accounting for some of the intergroup differences. Monocytes did not display numerical changes in either group. Regarding lymphocyte subpopulations, even though CD4+ T lymphocytes and B cells were depleted around 4 dpi in both infected groups, the main difference observed between both groups was in CD8+ T cells which displayed an earlier depletion in BVDV inoculated calves that can promote a greater BHV-1 dissemination, thus aggravating the course of the disease.
Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Vírus da Diarreia Viral Bovina/imunologia , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 1/imunologia , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/imunologia , Bovinos , Citometria de Fluxo/veterinária , Infecções por Herpesviridae/sangue , Infecções por Herpesviridae/complicações , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Contagem de Leucócitos/veterinária , Leucócitos Mononucleares , Subpopulações de Linfócitos/imunologia , Masculino , Distribuição AleatóriaRESUMO
Bluetongue virus serotypes 1 (BTV-1) and 8 (BTV-8) have been described as the most prevalent in Europe during recent outbreaks displaying intense virulence, sheep being among the most severely affected livestock species. However, BTV pathogenesis is still unclear. This study sought to elucidate differences in the pathogenetic mechanisms of BTV-1 and -8 in sheep. For this purpose, a time-course study was carried out, with sequential sacrifices in order to relate pathological lesions to changes in a range of virological and serological parameters. A greater virulence of BTV-1 was probed. BTV-1 infected sheep showed a longer clinical course, with a significant increase of clinical signs and more severe gross lesions than BTV-8 infected sheep. These differences appear not to be attributable to greater virus replication, suggesting viral loads did not influence in the pathogenicity of these serotypes. While both groups displayed an early, intense antibody response, they still developed clinical signs and lesions characteristic of bluetongue, indicating a lack of correlation between antibody levels and protection against the disease. Both acute phase response (APR) and thrombocytopenia induced by BTV-1 in sheep were more intense. Furthermore, an association between acute phase proteins (APPs) concentrations and the evolution of clinical signs and gross lesions was also observed, suggesting the existence of a direct link between the pathogenicity of BTV serotypes, the severity of vascular lesions and the serum concentrations of APPs. To our knowledge, this is the first verification of a measurable APR in sheep with both experimental and naturally occurring bluetongue.
Assuntos
Reação de Fase Aguda/veterinária , Coagulação Sanguínea , Vírus Bluetongue/patogenicidade , Bluetongue/patologia , Bluetongue/virologia , Proteínas de Fase Aguda/imunologia , Reação de Fase Aguda/virologia , Animais , Anticorpos Antivirais/imunologia , Bluetongue/sangue , Bluetongue/imunologia , Vírus Bluetongue/classificação , Vírus Bluetongue/imunologia , Vírus Bluetongue/fisiologia , Ovinos , VirulênciaRESUMO
In vitro studies have demonstrated that bluetongue virus (BTV)-induced vasoactive mediators could contribute to the endothelial cells dysfunction and increased vascular permeability responsible of lesions characteristic of bluetongue (BT) like oedema, haemorrhages and ischaemic necrosis in different tissues. However, few in vivo studies have been carried out to clarify the causes of these lesions. The aim of this study was to elucidate in vivo the pathogenetic mechanisms involved in the appearance of vascular lesions in different organs during BT. For this purpose, tissue samples from goats naturally infected with bluetongue virus serotype 1 (BTV-1) were taken for histopathological and immunohistochemical studies to determine the potential role of proinflammatory cytokines (tumour necrosis factor alpha, TNFα and interleukin one alpha, IL-1α) in the increased vascular permeability and their relationship with the presence of virus. Gross and histopathological examination revealed the presence of vascular damage leading to generalized oedema and haemorrhages. Immunohistochemical studies displayed that endothelial injury may have been due to the direct pathogenic effect of BTV infection on endothelial cells or may be a response to inflammatory mediators released by virus-infected endothelial cells and, possibly, other cell types such as monocytes/macrophages. These preliminary results of what appears to be the first in vivo study of tissue damage in small BT-infected ruminants suggest a direct link between the appearance of vascular changes and the presence of BTV-induced vasoactive cytokines.
Assuntos
Vírus Bluetongue/patogenicidade , Bluetongue/imunologia , Interleucina-1alfa/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Doenças Vasculares/patologia , Animais , Bluetongue/complicações , Bluetongue/patologia , Vírus Bluetongue/genética , Permeabilidade da Membrana Celular , Edema/etiologia , Edema/metabolismo , Ensaio de Imunoadsorção Enzimática , Cabras , Hemorragia/etiologia , Hemorragia/metabolismo , Técnicas Imunoenzimáticas , Mediadores da Inflamação/metabolismo , Interleucina-1alfa/genética , RNA Mensageiro/genética , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/genética , Doenças Vasculares/imunologia , Doenças Vasculares/virologiaRESUMO
Previous studies have shown that activation of effector caspase-3 is associated with the apoptosis of lymphocytes occurring during infection with bovine viral diarrhoea virus (BVDV); however, the regulation of the apoptosis pathways that induce cell death via activation of effector caspase-3 has not yet been clarified. The aim of this study was to examine immunohistochemically the expression of cleaved caspase (CCasp)-8 (initiator caspase of the extrinsic pathway), CCasp9 (initiator caspase of the intrinsic pathway) and Bcl-2 (an anti-apoptotic marker) in gut-associated lymphoid tissue (GALT) of the ileum from calves inoculated with a non-cytopathic strain of BVDV genotype-1. CCasp8 had similar expression to that of CCasp3. In interfollicular T-cell areas there was moderate apoptosis and evidence of moderate activation of initiator caspase-8. In B-cell follicles there was marked lymphocyte apoptosis and evidence of intense caspase-8 activation, highlighting the potentially major role of the extrinsic pathway in lymphocyte apoptosis in the GALT during BVDV infection. Additionally, there was a significant decrease in the number of CCasp9(+) cells from the start of the experiment and this was linked to inactivation of caspase-9. Therefore, the intrinsic pathway may play only a minor role in the induction of lymphocyte apoptosis. Finally, the observed overexpression of Bcl-2 protein could play a major role in protecting lymphocytes in the T-cell areas against apoptosis, while low levels of Bcl-2 expression could be associated with the follicular lymphocyte apoptosis occurring during BVDV infection.
Assuntos
Apoptose/fisiologia , Vírus da Diarreia Viral Bovina Tipo 1/imunologia , Tecido Linfoide/metabolismo , Animais , Linfócitos B/metabolismo , Linfócitos B/virologia , Caspase 8/metabolismo , Caspase 9/metabolismo , Bovinos , Vírus da Diarreia Viral Bovina Tipo 1/metabolismo , Tecido Linfoide/virologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismoRESUMO
To detect and monitor the sequential changes in virus levels, a reverse transcription quantitative real-time polymerase chain reaction assay using a TaqMan probe was carried out on frozen blood and tissues samples collected from calves experimentally infected with a non-cytopathic Bovine viral diarrhoea virus (BVDV) genotype 1 strain. Blood samples were collected among days 1-14 post-inoculation (p.i). On day 3 p.i, viral RNA was detected in blood samples from six of the eight inoculated animals. Viral RNA was detected in all remaining inoculated animals between 5 and 12 days p.i. The levels of viral RNA increased along the experiment, with a maximal peak between 6 and 9 days p.i. Analysis of virus load in tissues collected from calves euthanized on days 3, 6, 9 and 14 p.i displayed that BVDV was detected on day 3 p.i, being especially abundant in tonsils and ileocaecal valve, highlighting the role of tonsils as the main earliest viral replication sites as well as the principal source for virus spread to other lymphoid tissues and visceral organs. Coinciding with the highest viraemia levels, the highest viral loads were recorded at 9 days p.i. in tonsils, ileal lymph nodes, distal ileum and spleen, showing the main role of these secondary lymphoid organs in the pathogenic mechanisms of BVDV. However, virus levels in the liver and lung increased only towards the end of the infection. This fact could influence in the appearance of bovine respiratory diseases because of the capacity of BVDV for enhancing susceptibility to secondary infections.
Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Colostro , Vírus da Diarreia Viral Bovina Tipo 1 , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/imunologia , Bovinos , Valva Ileocecal/virologia , Íleo/virologia , Fígado/virologia , Pulmão/virologia , Linfonodos/virologia , Masculino , Tonsila Palatina/virologia , Reação em Cadeia da Polimerase , RNA Viral/isolamento & purificação , Baço/virologia , Timo/virologia , Distribuição Tecidual , Carga ViralRESUMO
The aim of this work was to investigate the susceptibility of calves infected with bovine viral diarrhea virus (BVDV) against secondary infections. For this purpose, the profile of cytokines implicated in the immune response of calves experimentally infected with a non-cytopathic strain of BVDV type-1 and challenged with bovine herpesvirus 1.1 (BHV-1.1) was evaluated in comparison with healthy animals challenged only with BHV-1.1. The immune response was measured by serum concentrations of cytokines (IL-1ß, TNFα, IFNγ, IL-12, IL-4 and IL-10), acute phase proteins (haptoglobin, serum amyloid A and fibrinogen) and BVDV and BHV-1.1 specific antibodies. BVDV-infected calves displayed a great secretion of TNFα and reduced production of IL-10 following BHV-1 infection, leading to an exacerbation of the inflammatory response and to the development of more intense clinical symptoms and lesions than those observed in healthy animals BHV-1-inoculated. A Th1 immune response, based on IFNγ production and on the absence of significant changes in IL-4 production, was observed in both groups of BHV-1-infected calves. However, whereas the animals inoculated only with BHV-1 presented an IFNγ response from the start of the study and high expression of IL-12, the BVDV-infected calves showed a delay in the IFNγ production and low levels of IL-12. This alteration in the kinetic and magnitude of these cytokines, involved in cytotoxic mechanisms responsible for limiting the spread of secondary pathogens, facilitated the dissemination of BHV-1.1 in BVDV-infected calves.