CC chemokine ligand 2 and CXC chemokine ligand 8 as neutrophil chemoattractant factors in canine idiopathic polyarthritis

Inflammatory response and MAPK and NF-κB pathway activation induced by natural street rabies virus infection in the brain tissues of dogs and humans

BACKGROUND

Street rabies virus (RABV) usually infects hosts at peripheral sites and migrates from motor or sensory nerves to the central nervous system. Several studies have found that inflammation is mild in a mouse model of street RABV infection. However, the pathogenetic mechanisms of street RABV in naturally infected dogs or humans are not well understood.

METHODS

Brain tissues collected from 3 dogs and 3 humans were used; these tissue samples were collected under the natural condition of rabies-induced death. The inflammatory response and pathway activation in the brain tissue samples of dogs and humans were evaluated by HE, IHC, ARY006, WB and ELISA. The clinical isolate street RABV strains CGS-17 and CXZ-15 from 30 six-week-old ICR mice were used to construct the mouse infection model presented here.

RESULTS

Neuronal degeneration and increased lymphocyte infiltration in the cerebral cortex, especially marked activation of microglia, formation of glial nodules, and neuronophagy, were observed in the dogs and humans infected with the street RABV strains. The various levels of proinflammatory chemokines, particularly CXCL1, CXCL12, CCL2, and CCL5, were increased significantly in the context of infection with street RABV strains in dogs and humans in relation to healthy controls, and the levels of MAPK and NF-κB phosphorylation were also increased in dogs and humans with natural infection. We also found that the degrees of pathological change, inflammatory response, MAPK and NF-κB signaling pathway activation were obviously increased during natural infection in dogs and humans compared with artificial model infection in mice.

CONCLUSION

The data obtained here provide direct evidence for the RABV-induced activation of the inflammatory response in a dog infection model, which is a relatively accurate reflection of the pathogenic mechanism of human street RABV infection. These observations provide insight into the precise roles of underlying mechanisms in fatal natural RABV infection.

Cytokine and Chemokine Profiling in Cats With Sepsis and Septic Shock

Background: Sepsis is a life-threatening condition associated with an exacerbated production of both pro- and anti-inflammatory cytokines that can promote a hyperactive response to infection or induce immunoparalysis. Data regarding the immune response to sepsis in cats are scarce. Establishing the profiles of cytokines and chemokines in feline sepsis to characterize the nature of the immune responses to sepsis might enable individualized treatments to be developed and targeted.

Objective: To evaluate the cytokine and chemokine network in cats with sepsis and septic shock, and to investigate the associations of these analytes with disease severity and outcome.

Methods: Blood samples prospectively collected at presentation of cats with sepsis and septic shock to two veterinary teaching hospitals were analyzed. Forty healthy cats were included as controls. A 19-plex feline cytokine/chemokine magnetic bead assay system was used to measure analytes in citrated plasma samples. Cytokine concentrations were compared between groups using the Kruskal-Wallis test with Dunn's post-hoc correction for multiple comparisons. Cytokine concentrations were compared between survivors and non-survivors with the Mann-Whitney U test. Odds ratios were calculated using logistic regression. A multivariable logistic regression model for prediction of septic shock was constructed.

Results: The study enrolled 35 septic cats. Many cytokines were undetectable in both sick and healthy control cats and were excluded from subsequent analyses. Comparisons of cytokine concentrations among healthy controls, cats with sepsis (n = 12) and cats with septic shock (n = 23) revealed that sick cats (sepsis or septic shock) had significantly higher plasma concentrations of IL-6, IL-8, KC-like, and RANTES compared to healthy controls. The combination of MCP-1, Flt-3L, and IL-12 was predictive of septic shock. None of the cytokines analyzed was predictive of outcome in this study population.

Conclusion: Plasma concentrations of IL-6, IL-8, KC-like, and RANTES are increased in cats with sepsis and may play important roles in pathogenesis. Multivariable modeling suggested that analysis of cytokines might aid differentiation of septic shock from sepsis. None of the cytokines analyzed was predictive of outcome. Measurement of these cytokines might enable future studies to better diagnose and characterize feline sepsis and septic shock.

Evaluation of the host cytokine response in dogs with sepsis and noninfectious systemic inflammatory response syndrome

OBJECTIVE

To quantify plasma cytokine concentrations in dogs with sepsis and noninfectious systemic inflammation and to evaluate the association between plasma cytokines and outcome in dogs with sepsis.

DESIGN

Prospective, observational cohort study.

SETTING

University teaching hospital.

ANIMALS

Forty-five dogs with sepsis, 10 dogs with noninfectious systemic inflammation (nSIRS), and 15 healthy controls were consecutively enrolled from June 2015 to February 2016 and followed to hospital discharge. Dogs with sepsis satisfied ≥2 SIRS criteria and had a documented or highly suspected bacterial infection. Dogs with nSIRS satisfied ≥2 SIRS criteria but had no evidence of infection. Dogs <3 kg and those with documented coagulopathy were excluded.

INTERVENTIONS

Measurement of inflammatory cytokines and high-mobility group box-1 (HMGB-1) was performed on each group.

MEASUREMENTS AND MAIN RESULTS

High-mobility group box-1 concentrations were analyzed by ELISA. Plasma concentrations of 13 cytokines were measured in singlet using multiplex magnetic bead assays. Kruskal-Wallis with Dunn's multiple comparison tests were used to compare biomarker concentrations between groups. Mann-Whitney U-tests were used to compare biomarker concentrations between survivors and nonsurvivors. Associations between biomarkers were evaluated using Spearman's correlation coefficients. Independent outcome predictors were identified using multivariable logistic regression. Alpha was set at 0.05. Concentrations of interleukin (IL)-6, C-X-C motif chemokine (CXCL)-8, keratinocyte-derived chemokine (KC)-like, C-C motif chemokine ligand 2 (CCL2), and HMGB-1 were significantly greater in dogs with sepsis versus healthy controls (all P ≤ 0.034). In dogs with sepsis, only CCL2 was independently associated with survival (odds ratio [OR] 0.996, 95% CI 0.993-0.999, P = 0.004). A cut-off of 385 pg/mL for CCL2 was 80% sensitive and 91.4% specific for nonsurvival (area under the ROC curve [AUROC] 0.866).

CONCLUSIONS

Dogs with sepsis have significantly increased concentrations of HMGB-1 and inflammatory cytokines, including IL-6, CXCL8, and KC-like. Increased CCL2 concentration is a negative prognostic indicator in dogs with sepsis. These findings should be confirmed using duplicate analyses in larger, distinct populations of dogs with sepsis before applying them to clinical patients.

Detection of anti-neutrophil cytoplasmic antibodies in dogs with immune-mediated inflammatory diseases

Anti-neutrophil cytoplasmic antibody (ANCA) is a type of autoantibody against neutrophil cytoplasm. In veterinary medicine, few studies have reported the detection of ANCA in dogs, and most of these studies were performed in dogs with inflammatory bowel disease (IBD). The aim of this study was to evaluate whether ANCA is detected in dogs with immune-mediated inflammatory diseases (IMIDs) other than IBD. Serum samples were collected before treatment initiation from 40 client-owned dogs with various diseases and 22 healthy beagle dogs; the dogs were classified into two groups: IMID group (n = 16) and control group (n = 46). ANCA was detected using the indirect fluorescent antibody test. Of the 16 dogs in the IMID group, 13 (81.3%) tested positive for ANCA. In contrast, of the 46 dogs in the control group, 13 (28.03%) tested positive for ANCA. Moreover, a significant association between ANCA positivity and IMIDs was identified in the IMID group than in the control group (P = 0.0003). In the control group, however, dogs with bacterial infection showed a relatively high rate of ANCA positivity. Therefore, ANCA positivity was observed in dogs with both IMIDs and bacterial infection. This suggested that ANCA positivity is associated with diseases accompanied by neutrophil activation and infiltration.