Identification of the Target Cells and Sequence of Infection during Experimental Infection of Ovine Fetuses with Cache Valley Virus

Cache Valley virus-induced malformations have been previously reproduced in ovine fetuses; however, no studies have established the course of infection of cells and tissues with Cache Valley virus. To address these questions, ovine fetuses at 35 days of gestation were inoculated in utero with Cache Valley virus and euthanized at 7, 10, 14, 21, and 28 days postinfection. On postmortem examination, arthrogryposis and oligohydramnios were observed in some infected fetuses. Morphological studies showed necrosis in the central nervous system and skeletal muscle of infected fetuses evaluated after 7 to 14 days postinfection, and hydrocephalus, micromyelia, and muscular loss were observed in infected fetuses after 21 to 28 days postinfection. Using immunohistochemistry and in situ hybridization, intense Cache Valley virus antigen and RNA staining was detected in the brain, spinal cord, skeletal muscle, and, to a lesser degree, in fetal membranes and other tissues of infected fetuses. Viral antigen and RNA staining decreased in targeted and infected tissues with the progression of the infection

Analysis of gene transcript profiling and immunobiology in Shetland sheepdogs with dermatomyositis

Dermatomyositis (DM) is a canine and human inflammatory disease of the skin and muscle that is thought to be autoimmune in nature. In dogs, DM occurs most often in the rough collie and Shetland sheepdog. Characteristic skin lesions typically develop on the face, ears, tail, and distal extremities. The severity of lesions varies and is thought to increase with stressful stimuli. Previous studies in the collie suggest that DM is inherited in an autosomal dominant fashion with incomplete penetrance. The work presented here concerns gene transcripts profiling and immunobiology of DM in the Shetland sheepdog. Gene transcript profiles were generated for affected and normal skin using a canine-specific oligonucleotide array having 49,929 probe sets. Two-hundred and eight-five gene transcripts, many of which are involved in immune function, were found to be differentially regulated in these tissues. Also reported are Western blot, immunohistochemistry, and immunofluorescence analyses which showed that staining patterns with sera from normal and affected dogs are quite similar. While our work suggests that canine DM is a disease that may be immune mediated, it did not detect the production of specific disease-associated autoantibodies. © 2008 ESVD and ACVD

Enhanced Myocardial Vascularity and Contractility by Novel FGF-1 Transgene in a Porcine Model of Chronic Coronary Occlusion

Background: Angiogenesis gene therapy has long been sought as a novel alternative treatment for restoring the blood flow and improving the contractile function of the ischemic heart in selected clinical settings. Angiogenic fibroblast growth factor-1 (FGF-1) is a promising candidate for developing a promising gene therapy protocol due to its multipotent ability to stimulate endothelial cell (EC) growth, migration, and tube formation. Despite these advantages, however, FGF gene therapy has suffered setbacks mainly due to the inefficient delivery rate of the growth factor in vivo. Given the potent angiogenic effect of FGF-1, we reasoned that constitutively synthesized minute quantities of this polypeptide hormone, when empowered with the ability to escape the cellular constraint, could freely act in a paracrine/autocrine fashion on nearby existing capillary plexuses and lead to neovascularization and restoration of the blood flow to ischemic tissues for reparative purpose. Methods: We report the direct gene transfer of a retroviral-based mammalian expression vector encoding a secreted form of FGF-1 (sp-FGF-1) for the purpose of therapeutic angiogenesis into the porcine myocardium subjected to the surgical placement of an ameroid occluder to induce the chronic coronary occlusion of the left circumflex coronary artery (LCx) and regional myocardial ischemia. Coronary angiography, performed 3 weeks after surgery, confirmed the interruption of the blood flow in the LCx distal to the site of ameroid placement. Results: Immunohistochemical analysis using antibody specific to von Willebrand factor (vWF), an endothelial marker, showed a significant increase (p<0.05) in myocardial vascularity in the sp-FGF-1 hearts compared to the control (vector alone). Importantly, an assessment of the cardiac function by echocardiography, performed 3 weeks after surgery, demonstrated improved cardiac contractility due to increased left ventricular free wall contraction in the sp-FGF-1-treated animals only. Conclusion: These results suggest that the intramyocardial delivery of our chimeric secretory FGF-1 gene can enhance vascularity and improve cardiac contractility in a chronic ischemic heart. This protocol may serve useful for developing reparative angiogenesis strategies aimed at improving the pumping function of the ischemic hearts in human patients

Mucosal expression of S100A12 (calgranulin C) and S100A8/A9 (calprotectin) and correlation with serum and fecal concentrations in dogs with chronic inflammatory enteropathy.

S100A12 and S100A8/A9 (calprotectin) are released from activated mononuclear cells and belong to the group of damage associated molecular patterns. Fecal S100A12 and S100A8/A9 concentrations have been suggested as biomarkers of intestinal inflammation in dogs with chronic inflammatory enteropathies (CIE). However, the mucosal cellular infiltrate in dogs with CIE is primarily lymphocytic-plasmacytic. Whether fecal S100A12 and S100A8/A9 levels reflect the number and/or activity of intestinal mucosal mononuclear cells, or whether these proteins are also produced by other cells has not been investigated. Thus, the aim of this study was to evaluate intestinal mucosal S100A12 and S100A8/A9 positivity and a potential relationship with the respective protein concentrations in serum and fecal samples in dogs with CIE. Serum (single sample), fecal samples (from 3 consecutive days), and gastrointestinal tissue biopsies (i.e., stomach, duodenum, ileum, and colon) were evaluated from 21 dogs with CIE. Serum and fecal S100A12 and S100A8/A9 concentrations were measured by analytically validated in-house ELISAs. Tissue biopsies underwent routine histopathology and immunohistochemical evaluation for S100A12 and S100A8/A9 positivity (S100A12+ and S100A8/A9+, each recorded as positive cells/mm2). S100A12+ and S100A8/A9+ cells were identified in all segments of the gastrointestinal tract, but were predominantly localized in the lamina propria (LP). Duodenal LP S100A12 positivity correlated statistically significantly with that in the stomach and ileum (ρ = 0.66 and 0.69, both p < 0.01), but was inversely correlated with the severity of macrophage infiltration in the duodenum (ρ=-0.47, p = 0.042). Ileal LP S100A8/A9 positivity correlated positively with the extent of ileal neutrophil and macrophage infiltration (ρ=0.61, p = 0.047). Fecal S100A12 concentrations strongly correlated with the number of S100A12+ cells along the entire gastrointestinal tract (ρ = 0.76, p = 0.028), whereas serum S100A12 concentrations were inversely correlated to colonic S100A12+ cell counts (ρ=-0.50, p = 0.043). Mucosal S100A8/A9+ cell counts were not associated with the corresponding fecal or serum S100A8/A9 concentrations. These results suggest that the intestinal mucosa in dogs with CIE contains an increased number of activated (pro-inflammatory) phagocytes expressing and secreting the S100A12 protein, but the macrophage population seen on routine histopathology is predominantly mature (anti-inflammatory) with a reduced or absent expression of S100A12 and a normal or increased expression of S100A8/A9. However, the distribution of intestinal S100A8/A9 expression requires further study

Validation of an enzyme-linked immunosorbent assay (ELISA) for the measurement of canine S100A12.

BACKGROUND Canine S100 calcium-binding protein A12 (cS100A12) shows promise as biomarker of inflammation in dogs. A previously developed cS100A12-radioimmunoassay (RIA) requires radioactive tracers and is not sensitive enough for fecal cS100A12 concentrations in 79% of tested healthy dogs. An ELISA assay may be more sensitive than RIA and does not require radioactive tracers. OBJECTIVE The purpose of the study was to establish a sandwich ELISA for serum and fecal cS100A12, and to establish reference intervals (RI) for normal healthy canine serum and feces. METHODS Polyclonal rabbit anti-cS100A12 antibodies were generated and tested by Western blotting and immunohistochemistry. A sandwich ELISA was developed and validated, including accuracy and precision, and agreement with cS100A12-RIA. The RI, stability, and biologic variation in fecal cS100A12, and the effect of corticosteroids on serum cS100A12 were evaluated. RESULTS Lower detection limits were 5 μg/L (serum) and 1 ng/g (fecal), respectively. Intra- and inter-assay coefficients of variation were ≤ 4.4% and ≤ 10.9%, respectively. Observed-to-expected ratios for linearity and spiking recovery were 98.2 ± 9.8% (mean ± SD) and 93.0 ± 6.1%, respectively. There was a significant bias between the ELISA and the RIA. The RI was 49-320 μg/L for serum and 2-484 ng/g for fecal cS100A12. Fecal cS100A12 was stable for 7 days at 23, 4, -20, and -80°C; biologic variation was negligible but variation within one fecal sample was significant. Corticosteroid treatment had no clinically significant effect on serum cS100A12 concentrations. CONCLUSIONS The cS100A12-ELISA is a precise and accurate assay for serum and fecal cS100A12 in dogs

Validation of the specificity of the mAb 2E4E4 against CD40 expressed in swine, bovine, ovine, and caprine spleen.

<p>Immunohistochemistry performed on: A) swine; B) bovine; C) ovine; and D) caprine spleen tissues probed with the mAb 2E4E4. Background reactivity was tested by probing E) swine, F) bovine, G) ovine, and H) caprine spleen tissues with an IgG1 isotype control mAb.</p

Characterization of a Broadly Reactive Anti-CD40 Agonistic Monoclonal Antibody for Potential Use as an Adjuvant

<div><p>Lack of safe and effective adjuvants is a major hindrance to the development of efficacious vaccines. Signaling via CD40 pathway leads to enhanced antigen processing and presentation, nitric oxide expression, pro-inflammatory cytokine expression by antigen presenting cells, and stimulation of B-cells to undergo somatic hypermutation, immunoglobulin class switching, and proliferation. Agonistic anti-CD40 antibodies have shown promising adjuvant qualities in human and mouse vaccine studies. An anti-CD40 monoclonal antibody (mAb), designated 2E4E4, was identified and shown to have strong agonistic effects on primary cells from multiple livestock species. The mAb recognize swine, bovine, caprine, and ovine CD40, and evoked 25-fold or greater proliferation of peripheral blood mononuclear cells (PBMCs) from these species relative to cells incubated with an isotype control (p<0.001). In addition, the mAb induced significant nitric oxide (p<0.0001) release by bovine macrophages. Furthermore, the mAb upregulated the expression of MHC-II by PBMCs, and stimulated significant (p<0.0001) IL-1α, IL6, IL-8, and TNF-α expression by PBMCs. These results suggest that the mAb 2E4E4 can target and stimulate cells from multiple livestock species and thus, it is a potential candidate for adjuvant development. This is the first study to report an anti-swine CD40 agonistic mAb that is also broadly reactive against multiple species.</p></div

Bovine, ovine, and caprine CD40 protein sequences have high homology to swine CD40 protein sequence.

<p>Alignment of swine, bovine, caprine, and ovine CD40 amino acid sequences. The signal sequence is shown where the consensus sequence is highlighted in green (amino acid 1–19), whereas the consensus sequence of the transmembrane domain is highlighted in red (amino acid 192–215). The percentage identity of the extracellular domains of bovine, ovine, and caprine CD40 protein sequences to that of swine is 74%, 75%, and 75%, respectively.</p

Upregulation of pro-inflammatory cytokine response by mAb 2E4E4.

<p>Intracellular cytokine staining was used to evaluate the ability of mAb 2E4E4 to stimulate upregulation of pro-inflammatory cytokines. Swine PBMCs were incubated with the mAb 2E4E4, LPS, or media alone, harvested at 12 hr. (Gray) and 24 hr. (Black), and then probed with mAbs against A) IL-1α; B) TNF-α; C) IL-6; or D) IL-8. Each column represents the mean florescent intensity of two wells ± SD. *p<0.05.</p