Pharmacologic Interventions to Immunologic and Immune-Mediated Conditions in Horses.

Immunomodulators can stimulate, suppress, or regulate one or many aspects of the immune response. Use of a variety of immunostimulants, immunosuppressors, and anti-inflammatory drugs are described in horses, but the evidence supporting their efficacy is variable. Corticosteroids and nonsteroidal anti-inflammatory drugs are the best characterized immunomodulators in horses, but further study is needed to fully define their ideal dosing protocols and indications and to characterize the efficacy of other immunomodulators in equine medicine.

Immunopathogenesis of the feline atopic syndrome.

BACKGROUND: Feline diseases of possible allergic origin with similar clinical phenotypes can have a varied underlying pathogenesis. Clinical phenotype, precise aetiology and underlying immunopathogenesis all need to be considered if advances in this neglected area of dermatology are to be made. OBJECTIVES: To document the status of research into the immunopathogenesis of the diseases that fall within the spectrum of the feline atopic syndrome (FAS ), to summarize the conclusions, identify the limitations and recommend future research directions. METHODS AND MATERIALS: A search of the literature was undertaken. The strengths and validity of the data and the contributions to our current understanding of the immunopathogenesis were analysed. Skin diseases of presumed allergic aetiology and asthma were assessed separately, as was the role of antibodies, cells and cytokines in each. RESULTS: The research varied in its quality and its impact often was limited by a failure to employ strict criteria in case selection. This reflected the difficulties of skin reaction patterns associated with a number of inciting causes. Research into feline asthma was handicapped by the difficulties of investigating clinical material, and much of the useful information was derived from experimental models. CONCLUSIONS AND CLINICAL IMPORTANCE: The evidence reviewed was supportive of a role for immunoglobulin (Ig)E in the pathogenesis of both feline atopic skin syndrome (FASS) and asthma, albeit not strongly so. The inflammation noted in both FASS and asthma is accompanied by eosinophils and lymphocytes, and these findings, together with the cytokine expression, are suggestive in some (not all) cats of T-helper type 2 immune dysregulation.

Transcriptome reveals the important role of metabolic imbalances, immune disorders and apoptosis in the treatment of Procambarus clarkii at super high temperature.

Temperature is an important environmental factor in the living environment of crustaceans. Changes in temperature can affect their normal growth and metabolism and even cause bacterial disease. Currently, the potential anti-reverse molecular reaction mechanism of crustaceans during high-temperature conditions has not yet been fully understood. Therefore, in this study, we characterised the transcriptome of Procambarus clarkii using RNA sequencing and performed a comparison between super-high-temperature treated samples and controls. After assembly and annotation, 81,097 unigenes with an average length of 069 bp and 358 differentially expressed genes (DEGs) were identified. Among these DEGs, 264 were differentially upregulated and 94 were differentially downregulated. To obtain comprehensive gene function information, we queried seven databases, namely, Nr, Nt, Pfam, KOG, Swiss-Prot, KEGG, and GO to annotate gene functions. Transcriptome analysis revealed that the identified DEGs have significant effects on immune-related pathways, including lysosomal and phagosomal pathways, and that super-high-temperature conditions can cause disease in P. clarkii. Some significantly downregulated genes are involved in oxidative phosphorylation and the PPAR signalling pathway; this suggests a metabolic imbalance in P. clarkia during extreme temperature conditions. In addition, elevated temperature changed the expression patterns of key apoptosis genes XIAP, CASP2, CASP2, CASP8, and CYTC, thereby confirming that high-temperature conditions caused immune disorders, metabolic imbalance, and, finally, triggered apoptosis. Our results provide a useful foundation for understanding the molecular mechanisms underlying the responses of P. clarkii during high-temperature conditions.

Serological markers of gluten sensitivity in Border terriers with gall bladder mucocoeles.

OBJECTIVES: To evaluate serological markers of gluten sensitivity in conjunction with cholecystokinin measurement in Border terriers with gall bladder mucocoeles. MATERIALS AND METHODS: Medical records from two referral hospitals were obtained between 2011 and 2019 to identify Border terriers with gall bladder mucocoeles, non-Border terriers with gall bladder mucocoeles and control Border terriers with non-biliary diseases. Enzyme-linked immunosorbent assays were performed on stored fasted serum samples for anti-gliadin IgG, anti-canine transglutaminase-2-IgA autoantibodies and cholecystokinin. Statistical analysis was performed using the Kruskall-Wallis test to identify differences between the groups. RESULTS: Fifteen Border terriers with gall bladder mucocoeles, 17 non-Border terriers with gall bladder mucocoeles and 14 control Border terriers with non-biliary diseases were recruited. Median transglutaminase-2-IgA autoantibodies in Border terriers with gall bladder mucocoeles was 0.73 (range: 0.18 to 1.67), which was significantly greater than in control Border terriers at 0.41 (0.07 to 1.14). Median cholecystokinin concentration in Border terriers with gall bladder mucocoeles was 13 pg/mL (6 to 45 pg/mL), which was significantly lower than in control Border terriers at 103 pg/mL (9 to 397 pg/mL). There was no difference in the anti-gliadin IgG between these groups. There was no difference observed in the non-Border terriers with gall bladder mucocoeles with either of the other groups. CLINICAL SIGNIFICANCE: Reduced cholecystokinin and increased transglutaminase-2-IgA autoantibodies was detected in Border terriers with gall bladder mucocoeles; which is in part homologous to gall bladder disease identified in human coeliac disease. The results suggest an immunological disease with impaired cholecystokinin release may be affecting gall bladder motility and possibly contributing to mucocoele formation in Border terriers.

Genetics of Immune Disease in the Horse.

Host defenses against infection by viruses, bacteria, fungi, and parasites are critical to survival. It has been estimated that upwards of 7% of the coding genes of mammals function in immunity and inflammation. This high level of genomic investment in defense has resulted in an immune system characterized by extraordinary complexity and many levels of redundancy. Because so many genes are involved with immunity, there are many opportunities for mutations to arise that have negative effects. However, redundancy in the mammalian defense system and the adaptive nature of key immune mechanisms buffer the untoward outcomes of many such deleterious mutations.

Nutrition as an etiological factor causing diseases in endangered huemul deer.

OBJECTIVES: Distinct diseases prevent endangered huemul deer (Hippocamelus bisulcus) recovery. Fundamental etiological factors include nutriments, a mayor component of habitat quality. Undernutrition affects growth, skeletal development, osteopathology, reproduction and immunocompetence: this paper amplifies data corroborating micro-nutrient deficiencies among huemul. RESULTS: In Argentina, 57% huemul cadavers exhibited osteopathology, with new cases reported here. Recently, 86% live huemul had osteopathology: cranial lesions involved antemortem tooth loss, reducing feeding efficiency and body condition, with starvation deaths. This population had tissues well deficient compared to other cervids, averaging 0.28 ppm selenium, 4.98 ppm copper, whereas for manganese 55% were deficient (2.52 ppm) and 45% adequate (42.79 ppm). Recently, lesions in one Chilean huemul were interpreted to stem from parapoxvirus. That population also has cases with cranial osteopathologies, high disease susceptibility (parapoxvirus, parasitism, foot lesions), crippled antlers, and low density, indicative of marginal habitat and primary etiological factors like undernutrition and immunosuppression. The reported atypical symptoms attributed to parapoxvirus may relate to probable diagnostic limitations, but does support presence of nutritional deficiencies. Patagonia has selenium deficient plants and livestock, including severe muscular dystrophy, and soil levels in extant huemul areas considered very deficient. Moreover, 73% of Chilean huemul were selenium deficient and 64% severely deficient with concomitant cranial osteopathology.

High incidence of anti-cytokine autoantibodies in dogs with immune diseases suggests important immuno-regulatory functions.

Autoantibodies against cytokines have been associated with immunodeficiency, susceptibility to infectious diseases, autoimmunity and inflammation in humans, but have not yet been investigated in the Veterinary field so far. The aim of the current study was to determine the presence of anti-cytokine autoantibodies in canines suffering from various conditions including recurrent infections, autoimmune diseases and cancer in comparison to healthy controls. This is the first report of the presence of autoantibodies against cytokines in dogs. A total of 101 serum samples (51 patients and 50 clinically healthy dogs) from the state of Mexico and surroundings were analysed using a multiplex bead-based flow cytometry assay. Results show significant levels of various anti-cytokine autoantibodies in diseased dogs but not in healthy controls. In addition we show distinct associations of various disease types to the specificity of anti-cytokine autoantibodies and to response complexities. Apart from the direct functional/causal implication of anti-cytokine auto-antibodies on disease processes, this findings point to the possibility to use anti-cytokine response patterns as diagnostic tools.

[Immunosuppressive therapy in dogs and cats. Properties of drugs and their use in various immune-mediated diseases]. / Immunsuppressive Therapie bei Hunden und Katzen. Eigenschaften von Wirkstoffen und ihre Anwendung bei verschiedenen immunvermittelten Erkrankungen.

Veterinarians are regularly faced with the diagnosis and therapy of immune-mediated diseases. More frequently occurring immune-mediated diseases are immune-mediated hemolytic anemia, immunemediated thrombocytopenia and polyarthritis. Glucocorticoids are commonly used as first-line treatment because of their availability, efficacy and rapid action. Nevertheless, some patients do not respond to glucocorticoid therapy alone. Others require a rapid dose reduction because of severe side effects from glucocorticoid treatment. These patients benefit from adjuvant therapies. Ciclosporin preparations are licensed for use in veterinary medicine. The use of azathioprine, mycophenolate mofetil and human immunoglobulin therapy has also been documented. This article describes the mode of action of certain immunosuppressive agents and their use in selected diseases from recent literature.

Evaluation of 5 methods for diagnosing failure of passive transfer in 160 Holstein calves.

BACKGROUND: Inadequate absorption of colostral IgG1 is termed failure of transfer of passive immunity (FTPI). Dairy calves with FTPI have increased mortality and morbidity in their first 6 months of life. OBJECTIVES: This study compared the clinical performance of 5 methods for diagnosing FTPI in Holstein calves. METHODS: An observational study was performed using 160 Holstein heifer calves. Serum was harvested at 48 hours of age, and FTPI was assessed using a digital Brix refractometer for total solids measurements, and digital refractometry and the biuret method to measure serum total protein (STP) concentrations. Serum gamma-glutamyltransferase activity was measured with an automated analyzer, and serum IgG was measured with the zinc sulfate turbidity test and an enzyme-linked immunosorbent assay. Diagnostic test performance was compared with that of the reference method (FTPI defined as a serum total IgG concentration <10 g/L). Test performance was evaluated using the area under the receiver operating characteristic curve, the sensitivity, the specificity, and the positive likelihood ratio at the optimal test cut point, and by calculating the kappa coefficient. RESULTS: A serum digital Brix percentage of <7.8% and an STP concentration of <52 g/L measured using digital refractometry were the best methods to identify calves with FTPI. The STP concentration measured with digital refractometry was 0.1 g/L lower than that measured with the biuret method. CONCLUSIONS: The digital Brix refractometer and the digital refractometer provide accurate and clinically useful methods for identifying dairy calves with FTPI. In this study, the excellent performance of the Brix refractometer was likely due to the use of a fixed sample volume (200 µL) and a uniform sample temperature at the time of measurement.

Ciclosporin and the cat: Current understanding and review of clinical use.

Practical relevance: Ciclosporin (CsA) is a systemic immuno-modulatory drug widely used to treat immune-mediated diseases in humans and veterinary species. CsA was registered for use in cats in the USA and Europe in 2011, and is indicated for the treatment of chronic allergic dermatitis at a recommended daily dose of 7 mg/kg PO. AUDIENCE: This review will be of interest to all veterinarians working with cats, given the wide range of potential applications of CsA and its safety profile. Although the drug is currently only licensed to treat chronic allergic dermatitis in cats, a small number of reports describe its use in non-dermatological conditions. Evidence base: This article reviews the mechanism of action, pharmacokinetics, drug interactions, adverse effects and clinical use of CsA, both for the licensed indication and for off-label use in the feline patient. Information presented has been summarised from the existing literature on CsA, with specific interest in studies carried out in cats. For its licensed indication, chronic allergic dermatitis, evidence provided includes randomised, placebo or prednisolone-controlled studies (EBM grade I) and prospective or retrospective open trials.

A Retrospective Study on the Safety and Efficacy of Leflunomide in Dogs.

BACKGROUND: Little clinical information is available concerning the use of leflunomide in dogs with immune-mediated diseases. OBJECTIVES: To report the safety and efficacy of leflunomide for the treatment of naturally occurring immune-mediated diseases in dogs. ANIMALS: Ninety-two dogs treated with leflunomide for management of suspected immune-mediated diseases. METHODS: Retrospective medical record review from Jan 1995 to Dec 2014. Data that were extracted from the medical records included signalment, body weight, underlying indication for leflunomide, dosage of leflunomide, treatment duration, concurrent medications, treatment response, and adverse events. RESULTS: Adverse events that could be related to leflunomide administration included diarrhea (3 of 92, 3.3%), lethargy (2 of 92, 2.2%), unexplained hemorrhage (3 of 92, 3.3%), thrombocytopenia (2 of 31, 6.5%), and increased liver enzyme activities (1 of 16, 6.3%). Significant dose differences between dogs with adverse events (n = 11; median, 2.9 mg/kg/d; range, 1.8-3.6 mg/kg/d) and dogs without adverse events (n = 81; median, 1.6 mg/kg/d; range, 0.8-4.3 mg/kg/d) were found (P < 0.001). Treatment response could be evaluated in 17 dogs. Of these 17 dogs, 12 dogs (70.5%) had an apparent positive response to the use of leflunomide. There was no significant difference (P = 0.22) in dosages between dogs that responded to leflunomide (n = 12; median, 1.9 mg/kg/d; range, 1.0-3.5 mg/kg/d) and those that did not respond (n = 5; median, 1.7 mg/kg/d; range, 1.0-2.0 mg/kg/d). CONCLUSIONS AND CLINICAL IMPORTANCE: Results suggest that the starting dosage of leflunomide should be 2 mg/kg/d rather than the currently suggested dosage of 3-4 mg/kg/d.

A novel RNAseq-assisted method for MHC class I genotyping in a non-model species applied to a lethal vaccination-induced alloimmune disease.

BACKGROUND: MHC class I genotyping is essential for a wide range of biomedical, immunological and biodiversity applications. Whereas in human a comprehensive MHC class I allele catalogue is available, respective data in non-model species is scarce in spite of decades of research. RESULTS: Taking advantage of the new high-throughput RNA sequencing technology (RNAseq), we developed a novel RNAseq-assisted method (RAMHCIT) for MHC class I typing at nucleotide level. RAMHCIT is performed on white blood cells, which highly express MHC class I molecules enabling reliable discovery of new alleles and discrimination of closely related alleles due to the high coverage of alleles with reads. RAMHCIT is more comprehensive than previous methods, because no targeted PCR pre-amplification of MHC loci is necessary, which avoids preselection of alleles as usually encountered, when amplification with MHC class I primers is performed prior to sequencing. In addition to allele identification, RAMHCIT also enables quantification of MHC class I expression at allele level, which was remarkably consistent across individuals. CONCLUSIONS: Successful application of RAMHCIT is demonstrated on a data set from cattle with different phenotype regarding a lethal, vaccination-induced alloimmune disease (bovine neonatal pancytopenia), for which MHC class I alleles had been postulated as causal agents.

Laparoscopic-assisted splenectomy in dogs: 18 cases (2012-2014).

OBJECTIVE: To describe the operative technique and perioperative outcome for laparoscopic-assisted splenectomy (LAS) in dogs. DESIGN: Retrospective case series. ANIMALS: 18 client-owned dogs. PROCEDURES: Medical records of dogs with naturally occurring disease of the spleen treated by means of LAS between 2012 and 2014 were reviewed. History, signalment, results of physical examination, results of preoperative diagnostic testing, details of surgical technique, intraoperative findings including results of abdominal exploration and staging, concurrent surgical procedures, complications, histopathologic diagnoses, duration of postoperative hospitalization, and perioperative outcome were recorded. The perioperative period was defined as the time from hospital admission for LAS until discharge or death (within the same visit). RESULTS: All dogs underwent initial abdominal exploration and staging via multiple 5-mm laparoscopic ports (n = 2) or a single commercially available multichannel port (16), followed by minilaparotomy with insertion of a wound retraction device, progressive exteriorization of the spleen, sealing of hilar vessels, and splenectomy. Splenectomy was performed for treatment of a splenic mass (n = 15), suspected neoplasia (2), or refractory immune-mediated disease (1). Median size (width × length) of splenic masses was 5 × 5 cm (range, 1.6 to 11.0 cm × 1.5 to 14.5 cm). Complications were limited to minor intraoperative hemorrhage in 1 dog; no patient required conversion to open laparotomy. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that LAS was technically feasible in dogs and not associated with major complications. Further evaluation is required; however, in appropriately selected patients, LAS may offer the benefits of a minimally invasive technique, including a smaller incision and improved illumination and magnification during exploration and staging.

Evaluation of a DLA-79 allele associated with multiple immune-mediated diseases in dogs.

Immune-mediated diseases are common and life-threatening disorders in dogs. Many canine immune-mediated diseases have strong breed predispositions and are believed to be inherited. However, the genetic mutations that cause these diseases are mostly unknown. As many immune-mediated diseases in humans share polymorphisms among a common set of genes, we conducted a candidate gene study of 15 of these genes across four immune-mediated diseases (immune-mediated hemolytic anemia, immune-mediated thrombocytopenia, immune-mediated polyarthritis (IMPA), and atopic dermatitis) in 195 affected and 206 unaffected dogs to assess whether causative or predictive polymorphisms might exist in similar genes in dogs. We demonstrate a strong association (Fisher's exact p = 0.0004 for allelic association, p = 0.0035 for genotypic association) between two polymorphic positions (10 bp apart) in exon 2 of one allele in DLA-79, DLA-79*001:02, and multiple immune-mediated diseases. The frequency of this allele was significantly higher in dogs with immune-mediated disease than in control dogs (0.21 vs. 0.12) and ranged from 0.28 in dogs with IMPA to 0.15 in dogs with atopic dermatitis. This allele has two non-synonymous substitutions (compared with the reference allele, DLA-79*001:01), resulting in F33L and N37D amino acid changes. These mutations occur in the peptide-binding pocket of the protein, and based upon our computational modeling studies, are likely to affect critical interactions with the peptide N-terminus. Further studies are warranted to confirm these findings more broadly and to determine the specific mechanism by which the identified variants alter canine immune system function.

Disease patterns and incidence of immune-mediated disease in insured Swedish Nova Scotia Duck Tolling Retrievers.

In this study, morbidity in insured Nova Scotia Duck Tolling Retriever (NSDTR) dogs from Sweden was investigated and compared with all other breeds and other retriever breeds. In addition to describing common morbidities in NSDTRs, the hypotheses that NSDTRs are predisposed to lymphoma, immune-mediated rheumatic disease (IMRD) and steroid-responsive meningitis-arteritis (SRMA) were tested. Included in the study were 445,336 dogs; of which, 2890 were NSDTRs that had been covered by veterinary insurance from the Agria Insurance Company (Stockholm, Sweden) at some point during the years 1995-2006. Incidences of various health problems were calculated using the number of veterinary visits as the numerator and the exact time at risk as the denominator. Overall, morbidity was higher in NSDTRs compared with all other breeds, but similar compared with other retriever breeds. The most common causes of veterinary visits in NSDTRs were injuries, gastrointestinal disease and locomotor disorders, with NSDTRs at increased risk of these compared with all other breeds. The incidences for IMRD, SRMA and lymphoma were significantly higher in NSDTRs than in all other dog breeds and all other retriever breeds. The study describes morbidity in NSDTRs, and identifies several disorders to which the breed is predisposed.

Disease patterns in 32,486 insured German shepherd dogs in Sweden: 1995-2006.

The aims of this retrospective study were to describe the morbidity and mortality in German shepherd dogs (GSD) in Sweden, based on insurance data, and to test the hypothesis that GSDs are predisposed to immune-related diseases. Morbidity was defined as incidence rates and based on veterinary care events. Mortality was defined as mortality rates and based on life insurance data. The study included 445,336 dogs, 7.3 per cent GSDs, covered by both veterinary care and life insurance between 1995 and 2006 in the Swedish insurance company Agria (Agria Insurance Company, Stockholm, Sweden). For veterinary care events (morbidity) GSDs were most over-represented for immunological disease, with a relative risk (RR) of 2.7, compared with the risk in all other breeds combined. The most common disease category (morbidity) in GSDs was skin disorders with an incidence rate of 346.8 cases per 10,000 dog years at risk. The highest RR for cause of death in GSDs compared with all other breeds was for skin conditions (RR=7.8). Locomotor disorders were the most common cause of death in GSDs. The GSD is predisposed to immune-related disorders, such as allergies, circumanal fistulae and exocrine pancreatic atrophy, with significantly increased risk compared with all other breeds.