Richard R. E. Uwiera

Recent advances in the use of DNA vaccines for the treatment of diseases of farmed animals

DNA-based vaccination constitutes one of the most recent approaches to vaccine development. This technology is in principle one of the most simple and yet versatile methods of inducing both humoral and cellular immune responses, as well as protection against a variety of infectious agents. However, although immune responses have been induced in a number of larger species, most information on the efficacy of DNA immunization has been generated in mice. In this review the information available to date about the use of DNA vaccines in farmed animals, including cattle, pigs and poultry, is presented. The areas that need specific attention in the future to bring this technology to the market are discussed, including the issues concerning delivery, safety, compatibility of plasmids in multivalent vaccines and the potential of using immune stimulants as part of a DNA vaccine.

Animal models to study acute and chronic intestinal inflammation in mammals.

Acute and chronic inflammatory diseases of the intestine impart a significant and negative impact on the health and well-being of human and non-human mammalian animals. Understanding the underlying mechanisms of inflammatory disease is mandatory to develop effective treatment and prevention strategies. As inflammatory disease etiologies are multifactorial, the use of appropriate animal models and associated metrics of disease are essential. In this regard, animal models used alone or in combination to study acute and chronic inflammatory disease of the mammalian intestine paired with commonly used inflammation-inducing agents are reviewed. This includes both chemical and biological incitants of inflammation, and both non-mammalian (i.e. nematodes, insects, and fish) and mammalian (i.e. rodents, rabbits, pigs, ruminants, dogs, and non-human primates) models of intestinal inflammation including germ-free, gnotobiotic, as well as surgical, and genetically modified animals. Importantly, chemical and biological incitants induce inflammation via a multitude of mechanisms, and intestinal inflammation and injury can vary greatly according to the incitant and animal model used, allowing studies to ascertain both long-term and short-term effects of inflammation. Thus, researchers and clinicians should be aware of the relative strengths and limitations of the various animal models used to study acute and chronic inflammatory diseases of the mammalian intestine, and the scope and relevance of outcomes achievable based on this knowledge. The ability to induce inflammation to mimic common human diseases is an important factor of a successful animal model, however other mechanisms of disease such as the amount of infective agent to induce disease, invasion mechanisms, and the effect various physiologic changes can have on inducing damage are also important features. In many cases, the use of multiple animal models in combination with both chemical and biological incitants is necessary to answer the specific question being addressed regarding intestinal disease. Some incitants can induce acute responses in certain animal models while others can be used to induce chronic responses; this review aims to illustrate the strengths and weaknesses in each animal model and to guide the choice of an appropriate acute or chronic incitant to facilitate intestinal disease.

Inflammation and epithelial cell injury in AIDS enteropathy: involvement of endoplasmic reticulum stress

Immunosuppressive lentivirus infections, including human, simian, and feline immunodeficiency viruses (HIV, SIV, and FIV, respectively), cause the acquired immunodeficiency syndrome (AIDS), frequently associated with AIDS enteropathy. Herein, we investigated the extent to which lentivirus infections affected mucosal integrity and intestinal permeability in conjunction with immune responses and activation of endoplasmic reticulum (ER) stress pathways. Duodenal biopsies from individuals with HIV/AIDS exhibited induction of IL‐1β, CD3ε, HLA‐DRA, spliced XBP‐1(Xbp‐1s), and CHOP expression compared to uninfected persons (P<0.05). Gut epithelial cells exposed to HIV‐1 Vpr demonstrated elevated TNF‐α., IL‐1β, spliced Xbp‐1s, and CHOP expression (P<0.05) together with calcium activation and disruption of epithelial cell monolayer permeability. In addition to reduced blood CD4+ T lymphocyte levels, viral loads in the gut and plasma were high in FIV‐infected animals (P<0.05). FIV‐infected animals also exhibited a failure to gain weight and increased lactulose/mannitol ratios compared with uninfected animals (P<0.05). Proinflammatory and ER stress gene expression were activated in the ileum of FIV‐infected animals (P<0.05), accompanied by intestinal epithelial damage with loss of epithelial cells and leukocyte infiltration of the lamina propria. Lentivirus infections cause gut inflammation and ensuing damage to intestinal epithelial cells, likely through induction of ER stress pathways, resulting in disruption of gut functional integrity.—Maingat, F., Halloran, B., Acharjee, S., van Marle, G., Church, D., Gill, M. J., Uwiera, R. R. E., Cohen, E. A., Meddings, J., Madsen, K., Power, C. Inflammation and epithelial cell injury in AIDS enteropathy: involvement of endoplasmic reticulum stress. FASEB J. 25, 2211‐2220 (2011). www.fasebj.org

Diets enriched in trans-11 vaccenic acid alleviate ectopic lipid accumulation in a rat model of NAFLD and metabolic syndrome

Trans11-18:1 (vaccenic acid, VA) is one of the most predominant naturally occurring trans fats in our food chain and has recently been shown to exert hypolipidemic effects in animal models. In this study, we reveal new mechanism(s) by which VA can alter body fat distribution, energy utilization and dysfunctional lipid metabolism in an animal model of obesity displaying features of the metabolic syndrome (MetS). Obese JCR:LA-cp rats were assigned to a control diet that included dairy-derived fat or the control diet supplemented with 1% VA. VA reduced total body fat (-6%), stimulated adipose tissue redistribution [reduced mesenteric fat (-17%) while increasing inguinal fat mass (29%)] and decreased adipocyte size (-44%) versus control rats. VA supplementation also increased metabolic rate (7%) concomitantly with an increased preference for whole-body glucose utilization for oxidation and increased insulin sensitivity [lower HOMA-IR (-59%)]. Further, VA decreased nonalcoholic fatty liver disease activity scores (-34%) and reduced hepatic (-27%) and intestinal (-39%) triglyceride secretion relative to control diet, while exerting differential transcriptional regulation of SREBP1 and FAS amongst other key genes in the liver and the intestine. Adding VA to dairy fat alleviates features of MetS potentially by remodeling adipose tissue and attenuating ectopic lipid accumulation in a rat model of obesity and MetS. Increasing VA content in the diet (naturally or by fortification) may be a useful approach to maximize the health value of dairy-derived fats.

A Unique Rodent Model of Cardiometabolic Risk Associated with the Metabolic Syndrome and Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, oligo-/anovulation, and polycystic ovarian morphology and is a complex endocrine disorder that also presents with features of the metabolic syndrome, including obesity, insulin resistance, and dyslipidemia. These latter symptoms form cardiometabolic risk factors predisposing individuals to the development of type 2 diabetes and cardiovascular disease (CVD). To date, animal models to study PCOS in the context of the metabolic syndrome and CVD risk have been lacking. The aim of this study was to investigate the JCR:LA-cp rodent as an animal model of PCOS associated with the metabolic syndrome. Metabolic indices were measured at 6 and 12 wk, and reproductive parameters including ovarian morphology and estrous cyclicity were assessed at 12 wk or adulthood. At 6 wk of age, the cp/cp genotype of the JCR:LA-cp strain developed visceral obesity, insulin resistance, and dyslipidemia (hypertriglyceridemia and hypercholesterolemia) compared with control animals. Serum testosterone concentrations were not significantly different between groups at 6 wk of age. However, at 12 wk, the cp/cp genotype had higher serum testosterone concentrations, compared with control animals, and presented with oligoovulation, a decreased number of corpora lutea, and an increased number of total follicles, in particular atretic and cystic follicles. The cardiometabolic risk factors in the cp/cp animals were exacerbated at 12 wk including obesity, insulin resistance, and dyslipidemia. The results of this study demonstrate that the JCR:LA-cp rodent may be a useful PCOS-like model to study early mechanisms involved in the etiology of cardiometabolic risk factors in the context of both PCOS and the metabolic syndrome.

Non-therapeutic administration of a model antimicrobial growth promoter modulates intestinal immune responses

BackgroundThe development of efficacious alternatives to antimicrobial growth promoters (AGP) in livestock production is an urgent issue, but is hampered by a lack of knowledge regarding the mode of action of AGP. The belief that AGP modulate the intestinal microbiota has become prominent in the literature; however, there is a lack of experimental evidence to support this hypothesis. Using a chlortetracycline-murine-Citrobacter rodentium model, the ability of AGP to modulate the intestinal immune system in mammals was investigated.ResultsC. rodentium was transformed with the tetracycline resistance gene, tet O, and continuous oral administration of a non-therapeutic dose of chlortetracycline to mice did not affect densities of C. rodentium CFU in feces throughout the experiment or associated with mucosal surfaces in the colon (i.e. at peak and late infection). However, chlortetracycline regulated transcription levels of Th1 and Th17 inflammatory cytokines in a temporal manner in C. rodentium-inoculated mice, and ameliorated weight loss associated with infection. In mice inoculated with C. rodentium, those that received chlortetracycline had less pathologic changes in the distal colon than mice not administered CTC (i.e. relative to untreated mice). Furthermore, chlortetracycline administration at a non-therapeutic dose did not impart either prominent or consistent effects on the colonic microbiota.ConclusionData support the hypothesis that AGP function by modulating the intestinal immune system in mammals. This finding may facilitate the development of biorationale-based and efficacious alternatives to AGP.

Increased risk of cardiovascular disease in Type 1 diabetes: arterial exposure to remnant lipoproteins leads to enhanced deposition of cholesterol and binding to glycated extracellular matrix proteoglycans

Diabet. Med. 28, 61–72 (2011)

Role of healing-specific-matricellular proteins and matrix metalloproteinases in age-related enhanced early remodeling after reperfused STEMI in dogs

We assessed whether aging augments left ventricular (LV) damage, remodeling, and dysfunction and alters expression of healing-specific-matricellular proteins (HSMPs), matrix metalloproteinases (MMPs) and other pertinent proteins after acute reperfused-ST-segment-elevation myocardial infarction (RSTEMI) in the dog model. The findings suggest a novel role for HSMPs, MMPs, and the other proteins in the age-related increase in LV damage, remodeling, and dysfunction. Potentially detrimental effects of the altered proteins appear to outweigh beneficial effects and contribute to adverse outcome. Deleterious changes include the increase in matrix-degrading MMPs, inducible nitric oxide synthase (iNOS) and pro-inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α, HSMPs such as secreted-protein-acidic-and-rich-in-cysteine (SPARC) and osteopontin (OPN), the blunted increase in endothelial-NOS (eNOS), and the decrease in IL-10 and neuronal NOS (nNOS). Potentially beneficial changes include increases in the HSMP secretory-leucocyte-protease-inhibitor (SLPI) and cytokine transforming growth factor (TGF)-β1. Targeting these proteins may mitigate enhanced LV remodeling and dysfunction with aging.

Tisseel and its effects on wound drainage post-thyroidectomy: prospective, randomized, blinded, controlled study.

OBJECTIVE This randomized, blinded, controlled study examines the effects of fibrin sealant (Tisseel, Laboratoire de production Baxter AG, Vienna, Austria) on wound drainage following thyroidectomy. METHODS Fifty-six consecutive patients were enrolled in the study. Patients were randomized into Tisseel and non-Tisseel treatment groups. Wound drain output was tallied in 8-hour increments by observers blinded to the treatment groups. RESULTS Fifty-six patients completed the study. Significant decreases in wound drainage were found in the first 8 hours in the Tisseel group. Eight hours postoperatively, wound output in the Tisseel group was reduced by 44% compared with the non-Tisseel group. A significant decrease in the total drainage over the 64-hour time period of 43% was noted between the treatment and control groups. Post-thyroidectomy wound drainage was reduced and trended to earlier drain removal. No significant changes in the length of hospital stay were noted, nor were postoperative complications encountered in either treatment group. CONCLUSIONS Fibrin sealants offer a unique opportunity to safely decrease post-thyroidectomy wound drainage. This investigation furthers the evidence that fibrin sealants could safely enable the implementation of drain-free thyroidectomies.

Comparative variation within the genome of Campylobacter jejuni NCTC 11168 in human and murine hosts.

Campylobacteriosis incited by C. jejuni is a significant enteric disease of human beings. A person working with two reference strains of C. jejuni National Collection of Type Cultures (NCTC) 11168 developed symptoms of severe enteritis including bloody diarrhea. The worker was determined to be infected by C. jejuni. In excess of 50 isolates were recovered from the worker’s stool. All of the recovered isolates and the two reference strains were indistinguishable from each other based on comparative genomic fingerprint subtyping. Whole genome sequence analysis indicated that the worker was infected with a C. jejuni NCTC 11168 obtained from the American Type Culture Collection; this strain (NCTC 11168-GSv) is the genome sequence reference. After passage through the human host, major genetic changes including indel mutations within twelve contingency loci conferring phase variations were detected in the genome of C. jejuni. Specific and robust single nucleotide polymorphism (SNP) changes in the human host were also observed in two loci (Cj0144c, Cj1564). In mice inoculated with an isolate of C. jejuni NCTC 11168-GSv from the infected person, the isolate underwent further genetic variation. At nine loci, mutations specific to inoculated mice including five SNP changes were observed. The two predominant SNPs observed in the human host reverted in mice. Genetic variations occurring in the genome of C. jejuni in mice corresponded to increased densities of C. jejuni cells associated with cecal mucosa. In conclusion, C. jejuni NCTC 11168-GSv was found to be highly virulent in a human being inciting severe enteritis. Host-specific mutations in the person with enteritis occurred/were selected for in the genome of C. jejuni, and many were not maintained in mice. Information obtained in the current study provides new information on host-specific genetic adaptation by C. jejuni.