The Chicken MHC: Insights into Genetic Resistance, Immunity, and Inflammation Following Infectious Bronchitis Virus Infections.

The chicken immune system has provided an immense contribution to basic immunology knowledge by establishing major landmarks and discoveries that defined concepts widely used today. One of many special features on chickens is the presence of a compact and simple major histocompatibility complex (MHC). Despite its simplicity, the chicken MHC maintains the essential counterpart genes of the mammalian MHC, allowing for a strong association to be detected between the MHC and resistance or susceptibility to infectious diseases. This association has been widely studied for several poultry infectious diseases, including infectious bronchitis. In addition to the MHC and its linked genes, other non-MHC loci may play a role in the mechanisms underlying such resistance. It has been reported that innate immune responses, such as macrophage function and inflammation, might be some of the factors driving resistance or susceptibility, consequently influencing the disease outcome in an individual or a population. Information about innate immunity and genetic resistance can be helpful in developing effective preventative measures for diseases such as infectious bronchitis, to which a systemic antibody response is often not associated with disease protection. In this review, we summarize the importance of the chicken MHC in poultry disease resistance, particularly to infectious bronchitis virus (IBV) infections and the role played by innate immunity and inflammation on disease outcome. We highlight how future studies focusing on the MHC and non-MHC genes can potentially bring clarity to observed resistance in some chicken B haplotype lines.

Effects of Chicken MHC Haplotype on Resistance to Distantly Related Infectious Bronchitis Viruses.

The major histocompatibility complex (MHC) B locus of chickens has been associated with resistance to different viral diseases. We previously provided evidence that chicken lines expressing MHC haplotypes B2 and B19 exhibit different resistance to a challenge with infectious bronchitis virus (IBV) Massachusetts 41 (M41). In the current study, we attempted to determine if those differences were true for genetically diverse IB viruses, i.e., IBV M41 and Arkansas-Delmarva poultry industry (ArkDPI). Clinical, pathologic, molecular, and immunologic outcomes were compared. Our results showed subtle clinical and pathologic differences between the two MHC chicken lines tested. Clinical differences were observed in respiratory signs at 2 days postinfection (dpi) in M41-infected birds. Pathologic differences were detected in viral load at 2 dpi in M41-infected birds and in tracheal epithelial thickness at 6 dpi in ArkDPI-infected birds. Substantial differences were observed in antibody responses at 14 dpi. The transcriptome analysis showed that B19 chickens highly expressed genes related to inflammatory and innate immune responses. This increased immune gene expression detected in B19 birds at 6 dpi did not lead to enhanced antibody production at 14 dpi. On the other hand, B2-haplotype chickens highly expressed genes related to cell responses, suggesting that B2 is able to diligently control the infection. Although not identical, genes triggered by M41 and ArkDPI are part of communal pathways and suggest similar immune and cell responses to both IBV genotypes. This work provides modest evidence for differential resistance to IBV by chickens displaying different MHC haplotypes as well as insights into the expression of a variety of genes after IBV replication in the host.

Efectos del haplotipo del complejo mayor de histocompatibilidad (MHC) del pollo sobre la resistencia a los virus de la bronquitis infecciosa relacionados de manera distante. El locus B del complejo mayor de histocompatibilidad (MHC) de los pollos se ha asociado con la resistencia a diferentes enfermedades virales. Previamente, se proporcionó evidencia de que las líneas de pollos que expresan los haplotipos B2 y B19 del MHC exhiben una resistencia diferente a un desafío con el virus de la bronquitis infecciosa (IBV) Massachusetts 41 (M41). En este estudio, se intentó determinar si esas diferencias eran verdaderas para virus de la bronquitis infecciosa genéticamente diversos como M41 y Arkansas DPI (Industria Avícola de Delmarva). Se compararon los resultados clínicos, patológicos, moleculares e inmunológicos. Los resultados mostraron diferencias clínicas y patológicas sutiles entre las dos líneas de pollo con diferente MHC que fueron analizadas. Se observaron diferencias clínicas en los signos respiratorios a los dos días postinfección en aves infectadas con M41. Se detectaron diferencias patológicas en la carga viral a los dos días después de la inoculación en aves infectadas con M41 y a los seis días después de la infección con Arkansas DPI. Se observaron diferencias sustanciales en las respuestas de anticuerpos al día 14 después de la inoculación. El análisis del transcriptoma mostró que los pollos B19 expresaban en gran medida los genes relacionados con las respuestas inmunes inflamatorias e innatas. Este aumento en la expresión de genes inmunes detectado en aves con haplotipo B19 a los seis días después de la inoculación no condujo a una mayor producción de anticuerpos a 14 días después de la inoculación. Por otro lado, los pollos con haplotipo B2 expresaron en gran medida los genes relacionados con las respuestas celulares, lo que sugiere que el haplotipo B2 es capaz de controlar de manera importante la infección. Aunque no son idénticos, los genes desencadenados por M41 y Arkansas DPI son parte de vías comunes y sugieren respuestas inmunes y celulares similares para ambos genotipos del virus de la bronquitis infecciosa. Este trabajo proporciona una evidencia modesta de la resistencia diferencial al virus de la bronquitis infecciosa por parte de los pollos que muestran diferentes haplotipos de MHC, así como información sobre la expresión de una variedad de genes después de la replicación del virus de la bronquitis infecciosa en el huésped.

Doenças neurológicas em gatos: 155 casos / Neurological diseases in cats: 155 cases

Foi realizado um estudo epidemiológico retrospectivo de gatos com doenças neurológicas atendidos em um Hospital Veterinário Universitário entre 2001 e 2014. O objetivo foi identificar e caracterizar a idade, o sexo, a raça, as doenças neurológicas e classificá-las de acordo com a região anatômica e o acrônimo DINAMIT-V. Foram observados 155 gatos com doenças neurológicas em 13 anos, sendo o diagnóstico confirmado em 112 gatos (72,2%) e presuntivo em 43 (27,8%). Gatos sem raça definida (77,9%) foram os mais comuns, seguido de gatos da raça persa e siamesa. Os locais mais afetados foram medula espinhal entre T3-L3 (28,4%) e tálamo-córtex (24,5%). A maioria dos gatos (43,9%) foi diagnosticada com doença traumática, principalmente trauma de medula espinhal, seguida de doença inflamatória/infecciosa (33,5%). Pode se concluir que a maior prevalência das doenças neurológicas de gatos envolve a medula espinhal e o tálamo-córtex, sendo as traumáticas as mais frequentes. Os dados obtidos podem auxiliar em futuros estudos sobre a frequência e a distribuição das principais doenças neurológicas em gatos.(AU)

A retrospective epidemiological study on neurological disease of cats was performed using data from cats admitted to a Veterinary Teaching Hospital from 2001 to 2014. The aim the study was to determine the age, sex race, and type of neurological disease affecting cats and identify these diseases according to the anatomical region and disease classes, specified under the acronym DINAMIT-V. One hundred and fifty five cats with neurological disease were observed during 13 years; the diagnosis was confirmed in 112 (72.2%) and was presumptive in 43 (27.8%). Mixed breed cats (77.9%) were the most commonly affected, followed by Persian and Siamese cats. The most affected anatomic sites were segments T3-L3 of the spinal cord (28.4%) and thalamic-cortical area (24.5%). Most cats (43.9%), were diagnosed with trauma, mainly spinal cord trauma, followed by inflammatory/infectious disease (33.5%). It is concluded that the neurological disorders in cats have higher prevalence in the spinal cord and thalamic-cortical areas and that the most frequent class of disease is trauma. Data obtained may assist future studies regarding neurological diseases in cats.(AU)

Light-driven photosensitizer uptake increases Candida albicans photodynamic inactivation.

Photodynamic Inactivation (PDI) is based on the use of a photosensitizer (PS) and light that results mainly in the production of reactive oxygen species, aiming to produce microorganism cell death. PS incubation time and light dose are key protocol parameters that influence PDI response; the correct choice of them can increase the efficiency of inactivation. The results of this study show that a minor change in the PDI protocol, namely light-driven incubation leads to a higher photosensitizer and more uniform cell uptake inside the irradiated zone. Furthermore, as the uptake increases, the damage caused by PDI also increases. The proposed light-driven incubation prior to the inactivation illumination dose has advantages when compared to the traditional PDI treatments since it can be more selective and effective. Using a violet light as pre-illumination (light-driven incubation) source and a red-light system as PDI source, it was possible to demonstrate that when compared to the traditional protocol of dark incubation, the pre-illuminated cell culture showed an inactivation increase of 7 log units. These in vitro results performed in Candida albicans cells may result in the introduction of a new protocol for PDI.

Epilepsia em cães: 66 casos (2005-2010) / Epilepsy in dogs: 66 cases (2005-2010)

O objetivo deste estudo foi identificar cães com epilepsia e obter informações a respeito da raça, do sexo, da idade, da classificação da epilepsia e da crise convulsiva, dos estágios e do período de ocorrência das crises convulsivas. Em 66,7% (44/66) dos cães a epilepsia foi primária, em 21,2% (14/66) sintomática e em 12,1% (8/66) provavelmente sintomática. Os cães sem raça definida (27%) foram os mais acometidos e a faixa etária predominou entre um e cinco anos de idade. A crise convulsiva generalizada tônico-clônica (66,7%) foi a mais observada, a procura pelo dono (72,7%) no período pré-ictal e o andar compulsivo (60,5%) no período pós-ictal foram os sinais mais encontrados e a ocorrência das crises convulsivas foi maior no período noturno (79,2%).

The objective of this study was to identify dogs with epilepsy and to obtain information about breed, sex, age, classification of the epilepsy and the seizures, as well as the stage and time of occurrence of the seizures. Epilepsy was primary in 66.7% (44/66) of dogs, symptomatic in 21.2% (14/66), and probably symptomatic in 12.1% (8/66). Crossbred dogs (27%) were the most affected and the predominant age group ranged from one to five years; the generalized tonic-clonic seizures (66.7%) was the most frequent presentation. The search for the owner (72.7%) during the preictal period and the compulsive walking (60.5%) in post-ictal period were the more frequent signs observed in the affected dogs, and the occurrence of seizures was higher at night (79.2%).