Expression of CD4 T cell cytokine genes in the colorectal mucosa of inflammatory colorectal polyps in miniature dachshunds

Inflammatory colorectal polyps (ICRPs) in miniature dachshunds are recently recognized as a major cause of large bowel diarrhea in this dog breed in Japan. ICRPs are characterized by the formation of multiple small polyps and a space-occupying large polyp in the colorectal area, and are thought to be a novel form of inflammatory bowel disease (IBD). In humans, specific cytokine patterns attributed to T helper (Th)1, Th17 and regulatory T cells have important roles in the pathogenesis of IBD. Thus, the aim of the present study was to assess the gene expression of cytokines of T cell subsets in the colorectal mucosa from dogs with ICRPs. Colorectal mucosal specimens from 10 dogs with ICRPs and 14 control dogs were used in this study. Interferon (IFN)-γ, interleukin (IL)-4, IL-17A and IL-10 mRNA expression was assessed using quantitative real-time PCR. IL-17A mRNA expression was significantly increased in large polyps compared to small polyps and controls. IFN-γ and IL-10 mRNA expression in large polyps were significantly higher than in controls. There was no significant difference in IL-4 mRNA expression among the three groups. IL-17A is thought to play important roles in the pathogenesis of ICRPs. IL-10 up-regulation could oppose the proinflammatory function of IL-17A.     

Cloning and expression of pigeon IFN-γ gene

This is the first paper describing the cloning of pigeon IFN-γ gene (PiIFN-γ) and the analysis of the in vitro expressed recombinant protein. The PiIFN-γ gene was identified by RT-PCR as a 498 bp, fragment coding for a precursor protein of 165 amino acids instead of 164 amino acids, as observed in the other avian species. The recombinant protein was expressed in vitro by an eukaryotic system and the biological properties of the cytokine were tested using a chicken macrophage cell line. The high degree of amino acid and nucleotide identity, shared with the ChIFN-γ, and the fact that the pigeon protein was functional on chicken cells, indicates a cross-reactivity between pigeon and chicken IFN-γ. The detection of the PiIFN-γ could represent an useful instrument in understanding the role played by this cytokine in immune response related to vaccinations and infectious diseases in the pigeon.     

In vivo kinetics of peripheral cellular immune responses in Mycobacterium avium subspecies paratuberculosis (MAP) infected and vaccinated goats

Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of paratuberculosis (ParaTB) also known as Johne’s disease (JD) in ruminants, which is characterized by chronic intestinal inflammation. A similar counterpart has been observed in the form of Crohn's disease in humans. The present study is the first trail in goats to understand the peripheral cellular immune responses following experimental MAP infection and vaccination. Fifteen apparently healthy male kids (3–6 months old) of Barbari breed were included in this study. In the experimental study, 5 kids were infected with ‘S 5’ strain of MAP (“Indian Bison Type”), 5 were vaccinated (Indigenous Vaccine) against MAP infection (Singh et al., 2007) and the remaining 5 kids were uninfected and non-vaccinated controls. Kids were observed for a period of 180 days post exposure (infection and vaccination) and were tested for development of infection. Cellular immune responses (in blood) were recorded post-exposure by three assays. We measured the frequencies of CD4 and CD8T cells, estimated plasma IFNγ and TNα and in the third assay, in vitro cytokine production by peripheral blood mononuclear cells (PBMCs) from vaccinated, infected and controls were examined in response to polyclonal stimulation. The frequencies of peripheral CD4 and CD8T cells were comparable in control, infected and vaccinated animals except around day 49 post-infection where MAP infected animals showed a trend towards significantly reduced frequencies of CD4 T cells compared to apparently healthy controls. Significantly reduced plasma TNFα levels were also observed in infected animals compared to vaccinated animals,during the course of infection. Diminished levels (although non significant) of TNFα were observed in the supernatants from polyclonally stimulated PBMCs at around day 49 post infection. It is conceivable that the diminished cellular immune responses may coincide with an impairment (immune exhaustion) of perhaps antigen-specific CD4T cells that might, in the course of infection, contribute to the progressive nature of caprine paratuberculosis.     

PD-1 and PD-L1 regulate cellular immunity in canine visceral leishmaniasis

PD-1 is a negative costimulator of chronic infectious diseases In this study, we investigated the expression of PD-1 and its ligands in the spleen of dogs with visceral leishmaniasis and lymphoproliferative response to soluble antigen, in lymph node cells in the presence or absence of antibodies blocking PD-1 and its ligands. Our results showed expression of PD-1 and its ligands is higher after L. infantum infection and in the spleen of infected dogs, PD-1 blockage was able to restore the antigen-dependent lymphoproliferative response and regulated production of the cytokines IL-4 and IL-10 and NO production. We concluded that L. infantum infection modulates PD-1 and its ligands expression in canine VL and that blockage of PD-1 restores the immune response. Thus, blockage of PD-1 is a target for therapeutic drug development.     

Tumor Necrosis Factor and Interleukin-6 Activity and Endotoxin Concentration in Peritoneal Fluid and Blood of Horses with Acute Abdominal Disease

The purpose of this study was to evaluate the diagnostic and prognostic significance of tumor necrosis factor-alpha (TNF) and interleukin-6 (IL-6) activities and endotoxin concentration in blood and peritoneal fluid of 155 adult horses with acute abdominal disease (colic). Samples also were obtained from 20 healthy adult horses. Blood and peritoneal fluid supernatant TNF and IL-6 activities and endotoxin concentration were significantly greater in horses with colic, compared with healthy horses. In horses with colic, the peritoneal fluid endotoxin concentration and TNF and IL-6 activities were significantly greater than those in blood. Within the colic group, peritoneal fluid IL-6 activity was the analyte that was most frequently increased. Blood and peritoneal fluid supernatant TNF and IL-6 activities were significantly greater when endotoxin was detected in the same sample. Blood and peritoneal fluid IL-6 activity was significantly greater in horses with inflammatory or strangulating lesions, compared with horses having nonstrangulating or noninflammatory lesions. Compared with all other data categories, diagnostic accuracy for nonsurvival was greatest (80%) when blood IL-6 activity exceeded 60 units/mL. The results of this study indicate that endotoxin was present in the peritoneal cavity of at least one third of horses with any acute disease of the abdomen. In horses presented for colic, blood or peritoneal fluid IL-6 activity was more useful than either TNF activity or endotoxin concentration for distinguishing lesion type. Although diagnostic accuracy for the prediction of nonsurvival was good for all of the analytes, negative values were more useful in the prediction of a favorable outcome than were abnormally increased values in the prediction of mortality.     

n-3多不饱和脂肪酸对动物炎症·免疫和细胞因子的调节作用

综述了n-3多不饱和脂肪酸对动物炎症、感染和细胞因子的作用效果。     

Alteration in lymphocyte responses,cytokine and chemokine profiles in chickens infected with genotype VII and VIII velogenic Newcastle disease virus

Newcastle disease (ND) is a highly contagious avian disease and one of the major causes of economic losses in the poultry industry. The emergence of virulent NDV genotypes and repeated outbreaks of NDV in vaccinated chickens have raised the need for fundamental studies on the virus–host interactions. In this study, the profiles of B and T lymphocytes and macrophages and differential expression of 26 immune-related genes in the spleen of specific-pathogen-free (SPF) chickens, infected with either the velogenic genotype VII NDV strain IBS002 or the genotype VIII NDV strain AF2240, were evaluated. A significant reduction in T lymphocyte population and an increase in the infiltration of IgM⁺ B cells and KUL01⁺ macrophages were detected in the infected spleens at 1, 3 and 4 days post-infection (dpi) (P < 0.05). The gene expression profiles showed an up-regulation of CCLi3, CXCLi1, CXCLi2 (IL-8), IFN-γ, IL-12α, IL-18, IL-1β, IL-6, iNOS, TLR7, MHCI, IL-17F and TNFSF13B (P < 0.05). However, these two genotypes showed different cytokine expression patterns and viral load. IBS002 showed higher viral load than AF2240 in spleen at 3 and 4 dpi and caused a more rapid up-regulation of CXCLi2, IFN-γ, IL-12α, IL-18, IL-1β, iNOS and IL-10 at 3 dpi. Meanwhile, the expression levels of CCLI3, CXCLi1, IFN-γ, IL-12α, IL-1β and iNOS genes were significantly higher in AF2240 at 4 dpi. In addition, the expression levels of IL-10 were significantly higher in the IBS002-infected chickens at 3 and 4 dpi. Hence, infection with velogenic genotype VII and VIII NDV induced different viral load and production of cytokines and chemokines associated with inflammatory reactions.     

Blood Levels of Selected Metabolic Factors,Cytokines, and Lymphocyte Subpopulations in Arabian and Thoroughbred Horses During the Longest and Shortest Days of the Year

Day length-related alterations of several metabolic factors (glucose, leptin, insulin, and insulin-like growth factor-1 [IGF-1]), cytokines (interleukin-2 [IL-2], IL-4, IL-6, tumor necrosis factor-alpha [TNF-α], interferon-gamma [IFN-γ], and lymphocyte subpopulations [CD2, CD3, CD4, CD8, CD19, natural killer (NK) cells) were evaluated in Arabian and Thoroughbred horses. Plasma glucose, leptin, IGF-1, insulin, and cytokines levels were measured on the longest day of the breeding season and on the shortest day of the nonbreeding season. Determination of lymphocyte subpopulations was performed by flow cytometry. Glucose and IL-2 levels, CD4:CD8 ratio, and NK cells showed variations that depended on the day length. Mean concentrations of plasma leptin were higher in Arabian horses than in Thoroughbred horses, whereas mean concentrations of IGF-1 and IL-2 were lower in Arabian horses. Day length-by-breed-by-gender interaction was found for insulin, IFN-γ, and IL-4 levels. An interaction was also found between day length and gender for the expressions of CD2, CD3, CD8, and CD19. Correlations were detected between expression of CD8⁺ cells and levels of TNF-α and IFN-γ and between percentages of NK cells and levels of IGF-1, insulin, and glucose. Results suggested that day length and, therefore, season are important determinants or factors in modulating the immune system and could affect lymphocyte subpopulations depending on the sex of the horse. Additionally, it seems that a complex relationship in horses, as in humans and mice, exists between the immune and metabolic system, which changes according to day length, breed, and gender.     

Mucosal mRNA Cytokines’ Profile of Gastric Wall in Neonatal Foals: Comparison with Endoscopy and Histology

Gastritis and gastric ulcerations occur frequently in neonatal foals. The relationship between cytokines expressed by gastric mucosa and gastric histopathology in healthy or sick foals has never been investigated. The aim of this study was to compare the histological diagnosis and endoscopic view with cytokine expression (TNF-α, IL-1β, IL-4, IL-8, IL-13, and IFN-γ) of gastric mucosa. Twenty-two foals were definitively enrolled in the study: 19 were critically ill, and 3 were healthy foals. Gastric biopsy specimens were collected for histological examination and for cytokine mRNA qualitative real-time PCR analysis. This study shows that there is a substantial agreement between histology and endoscopy and that foals with evidence of gastritis and gastric ulcerations have higher probability of expressing TNF-α. Moreover, the overall profile of cytokines expression, with a low percentage of IFN-γ, a high percentage of IL-4, and the absence of IL-13, suggests a down-regulation of the Th1 cell-mediated immune response and an impaired Th2 response in the gastric wall in the neonatal period.     

Pathophysiology of acute pancreatitis: potential application from experimental models and human medicine to dogs

The cellular events leading to pancreatitis have been studied extensively in experimental models. Understanding the cellular events and inciting causes of the multisystem inflammatory cascades that are activated with this disease is of vital importance to advance diagnosis and treatment of this condition. Unfortunately, the pathophysiology of pancreatitis in dogs is not well understood, and extrapolation from experimental and human medicine is necessary. The interplay of the inflammatory cascades (kinin, complement, cytokine) is extremely complex in both initiating leukocyte migration and perpetuating disease. Recently, nitric oxide (NO) and altered microcirculation of the pancreas have been proposed as major initiators of inflammation. In addition, the role of the gut is becoming increasingly explored as a cause of oxidative stress and potentiation of systemic inflammation in pancreatitis.