Time Series Transcriptomic Analysis of Bronchoalveolar Lavage Cells from Piglets Infected with Virulent or Low-Virulent Porcine Reproductive and Respiratory Syndrome Virus 1.

Porcine reproductive and respiratory syndrome virus (PRRSV) has evolved to escape the immune surveillance for a survival advantage leading to a strong modulation of host's immune responses and favoring secondary bacterial infections. However, limited data are available on how the immunological and transcriptional responses elicited by virulent and low-virulent PRRSV-1 strains are comparable and how they are conserved during the infection. To explore the kinetic transcriptional signature associated with the modulation of host immune response at lung level, a time-series transcriptomic analysis was performed in bronchoalveolar lavage cells upon experimental in vivo infection with two PRRSV-1 strains of different virulence, virulent subtype 3 Lena strain or the low-virulent subtype 1 3249 strain. The time-series analysis revealed overlapping patterns of dysregulated genes enriched in T-cell signaling pathways among both virulent and low-virulent strains, highlighting an upregulation of co-stimulatory and co-inhibitory immune checkpoints that were disclosed as Hub genes. On the other hand, virulent Lena infection induced an early and more marked "negative regulation of immune system process" with an overexpression of co-inhibitory receptors genes related to T-cell and NK cell functions, in association with more severe lung lesion, lung viral load, and BAL cell kinetics. These results underline a complex network of molecular mechanisms governing PRRSV-1 immunopathogenesis at lung level, revealing a pivotal role of co-inhibitory and co-stimulatory immune checkpoints in the pulmonary disease, which may have an impact on T-cell activation and related pathways. These immune checkpoints, together with the regulation of cytokine-signaling pathways, modulated in a virulence-dependent fashion, orchestrate an interplay among pro- and anti-inflammatory responses. IMPORTANCE Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the major threats to swine health and global production, causing substantial economic losses. We explore the mechanisms involved in the modulation of host immune response at lung level performing a time-series transcriptomic analysis upon experimental infection with two PRRSV-1 strains of different virulence. A complex network of molecular mechanisms was revealed to control the immunopathogenesis of PRRSV-1 infection, highlighting an interplay among pro- and anti-inflammatory responses as a potential mechanism to restrict inflammation-induced lung injury. Moreover, a pivotal role of co-inhibitory and co-stimulatory immune checkpoints was evidenced, which may lead to progressive dysfunction of T cells, impairing viral clearance and leading to persistent infection, favoring as well secondary bacterial infections or viral rebound. However, further studies should be conducted to evaluate the functional role of immune checkpoints in advanced stages of PRRSV infection and explore a possible T-cell exhaustion state.

Molecular analysis of lungs from pigs immunized with a mutant transferrin binding protein B-based vaccine and challenged with Haemophilus parasuis.

The molecular analysis of pigs vaccinated with a mutant transferrin-binding protein B (Y167A) from Haemophilus parasuis was compared with that performed for unvaccinated challenged (UNCH) and unvaccinated unchallenged (UNUN) pigs. Microarray analysis revealed that UNCH group showed the most distinct expression profile for immune response genes, mainly for those genes involved in inflammation or immune cell trafficking. This fact was confirmed by real-time PCR, in which the greatest level of differential expression from this group were CD14, CD163, IL-8 and IL-12. In Y167A group, overexpressed genes included MAP3K8, CD14, IL-12 and CD163. Proteomics revealed that collagen α-1 and peroxiredoxins 2 and 6 were overexpressed in Y167A pigs. Our study reveals new data on genes and proteins involved in H. parasuis infection and several candidates of resistance to infection that are induced by Y167A vaccine. The expression of proinflammatory molecules from Y176A pigs is similar to their expression in UNUN pigs.

Iron status in blood donor dogs.

BACKGROUND: Despite the popularity of canine blood donor (BD) programs, there is scarce scientific information regarding iron status in this canine population of dogs. OBJECTIVE: To assess iron status in dogs used in a blood donor program. ANIMALS: A total of 130 healthy dogs (75 BD, 55 controls [C]) were included. A subset of dogs (n = 12) were used to evaluate the effects of repetitive donations by having a second and more recent sample analyzed. METHODS: Serum iron concentration (SI), unsaturated iron-binding capacity (UIBC), total iron-binding capacity (TIBC), and percentage transferrin saturation (%SAT) were obtained. Values were compared using a 2-way ANOVA (factors: BD status, breed). For the subset of BD, the first sample (less frequent donors -LD-, after a mean of 3.8 donations) was compared to a second sample (experienced donors -ED-, mean 13.6 donations) using a paired t-test. RESULTS: SI (183.7 ± 55.3 µg/dL) and %SAT (55.7 ± 17.4%) were higher and UIBC (152.6 ± 73.3 µg/dL) was lower in BD dogs than in C (153.9 ± 51.7 µg/dL, 43.8 ± 17.8%, and 224.1 ± 120.6 µg/dL, respectively). Also, UIBC and TIBC were lower, and %SAT higher in Greyhounds when compared with non-Greyhounds. ED had decreased %SAT and increased UIBC and TIBC when compared with LD. CONCLUSIONS AND CLINICAL IMPORTANCE: Our canine BD population did not have iron deficiency and had higher SI concentration than C. However, ED (~14 consecutive blood donations every ~8 weeks) developed a mild iron deficiency, although values were still within canine reference intervals. Greyhounds have higher %SAT than non-Greyhounds, which might be a breed-specific peculiarity.

Markers of iron metabolism in retired racing Greyhounds with and without osteosarcoma.

BACKGROUND: Greyhounds have well-described clinicopathologic idiosyncrasies, including a high prevalence of osteosarcoma (OSA). Hematocrit, HGB, and HGB oxygen affinity are higher than in other dogs, while haptoglobin concentration is lower, so we hypothesized that Greyhounds have a different iron metabolism. To our knowledge, there are no reports on serum iron profiles in Greyhounds. OBJECTIVES: To elucidate iron metabolism in Greyhounds, we wanted to compare serum iron concentration, total iron-binding capacity (TIBC), and percent transferrin saturation (%SAT) in healthy retired racing Greyhounds (RRGs) with OSA (RRGs - OSA), and also with non-Greyhounds (NGs), without and with OSA (NGs - OSA). METHODS: Serum iron concentration and unsaturated iron-binding capacity (UIBC) were measured by standard methods, and TIBC and %SAT were calculated in RRGs (n = 25), RRGs - OSA (n = 28), NGs (n = 30), and NGs - OSA (n = 32). RESULTS: TIBC was lower in RRGs than in NGs (P < .0001), and in RRGs - OSA than in NGs - OSA (P < .0001). NGs - OSA had lower TIBC than healthy NGs (P = .003). Percent SAT was higher in RRGs than in NGs (P < .0001) and in RRGs - OSA (P = .008), and %SAT was also lower in NGs than in NGs - OSA (P = .004). Percent SAT was also higher in RRGs - OSA than in NGs - OSA (P = .001). Both RRGs - OSA (P = .02) and NGs - OSA (P < .0001) had lower serum iron concentrations than their healthy counterparts. CONCLUSION: Lower TIBC and higher %SAT may constitute another Greyhound idiosyncrasy compared with other dogs. In this study, all dogs with OSA had higher serum iron concentrations and %SAT than healthy dogs.

Haematological and biochemical values in North American Scottish deerhounds.

OBJECTIVE: Sighthounds, including deerhounds, have unique physiological traits that result in laboratory test results that may lie outside reference intervals for the general dog population. Although reference intervals for most analytes are thought to be similar among sighthounds, breed-specific reference intervals are available mainly for greyhounds. The aim of this study was to establish reference intervals for haematology and serum biochemical profiles in deerhounds. METHODS: Venous blood samples were collected from healthy deerhounds. Haematological and biochemical analytes were examined and reference intervals were established using the 5th and 95th percentiles. RESULTS: The reference intervals obtained from 96 dogs for platelets, reticulocytes, total thyroxine, chloride, gamma glutamyl transferase, bilirubin and glucose were lower than the general dog population. Reference intervals for mean cell volume, potassium, urea, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and cholesterol were higher than the general dog population. Reference intervals for eosinophils and globulin were wider than that of the general population. CLINICAL SIGNIFICANCE: These results confirm that differences in haematological and biochemical values exist in the deerhound. Some appear to be shared by all sighthounds but others may be unique to this breed.

Haematological, blood gas and acid-base values in the Galgo Español (Spanish greyhound).

OBJECTIVES: Haematologic profiles, electrolyte concentrations, blood gas values and acid-base balance have been studied and reported in healthy greyhounds; however, there is only one study published on blood gas values in Galgos Españoles. Because of their purported common origins with greyhounds (same group and class), it was hypothesised that Galgos Españoles also have differences in haematologic values, electrolyte concentrations, blood gas values and acid-base balance compared to other non-sporting breeds. METHODS: Venous blood samples from 30 Galgos Españoles and 20 dogs from different breeds were collected, and complete blood counts, electrolyte concentrations, blood gas values and acid-base balance were measured. RESULTS: From the 24 parameters analysed, 5 had statistically significant differences (P<0·05). Galgos Españoles had higher haematocrit (P<0·001), haemoglobin concentration (P=0·003), erythrocyte count (P=0·016) and pH (P=0·03), and lower platelet count (P=0·005), than those in other-breed dogs. CLINICAL SIGNIFICANCE: These results confirm that significant haematologic differences exist in Galgos Españoles when compared with other dogs, although these differences are not as striking as in greyhounds. Practitioners need to be aware of these breed-specific differences in order to make accurate diagnoses in Galgos Españoles.

Clinical pathology of Greyhounds and other sighthounds.

Owing to the development of Greyhounds as racing sighthounds, these dogs have acquired unique physiologic adaptations that distinguish them from other breeds. Reference intervals for many analytes in retired racing Greyhounds (RRGs) differ from those of other breeds; most of the hematologic differences have also been described in other sighthounds. In this review, we provide a survey of the literature on clinical pathology of Greyhounds and other sighthounds and results of laboratory testing, including analysis of CBCs, biochemical profiles, coagulation tests, and blood gases, in RRGs at The Ohio State University. Major clinicopathologic differences in this breed include higher RBC mass, creatinine concentration, glomerular filtration rate, activities of hepatic enzymes, and concentration of cardiac troponin, as well as lower WBC, neutrophil, and platelet counts, thromboelastographic values, and concentrations of serum haptoglobin, total globulins, and T4.

Thromboelastography in healthy, sick non-septic and septic neonatal foals.

OBJECTIVES: To evaluate citrated recalcified thromboelastography (TEG) in healthy newborn foals, and to determine intra-assay, inter-individual and intra-individual (at 12 h, 24 h and 7 days after birth) variations. Additionally, to compare TEG variables, haematological values and conventional coagulation profiles from healthy, sick non-septic, and septic foals. DESIGN: Prospective study. METHODS: The study group comprised 18 healthy, 15 sick non-septic and 17 septic foals. Two citrated (3.2%; 1 : 9 anticoagulant : blood ratio) blood samples were submitted for haemostatic evaluation using a TEG analyser and conventional coagulation profile. TEG values (R time (R), K time (K), angle (α), maximum amplitude (MA) and G value (G)), complete blood count (CBC) and conventional coagulation profile (prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration (Fib) and antithrombin (AT)) were evaluated. Signalment, presenting complaint, sepsis scores, blood culture results and outcome were taken from the medical records of the sick foals. RESULTS: Mean values ± SD for TEG variables in healthy neonatal foals were: R = 11.82 ± 5.35 min, K = 3.06 ± 1.34 min, α= 51.19 ± 12.66 degrees, MA = 55.06 ± 6.67 mm and G = 6361 ± 1700 dyn/cm(2) . Mean coefficients of variation for intra-assay/inter-individual/intra-individual in healthy foals were: R = 3.5/45.2/43.1%; K = 5.3/58.7/28.7%; α= 1.5/24.7/11.9%; MA = 0.3/12.1/6.1%; G = 1.6/26.7/14.7%. Septic foals had significantly greater α, MA and G values than sick non-septic foals, and significantly greater MA and G than healthy foals, changes that are consistent with hypercoagulability. Weak correlations were detected between TEG variables and haematological or haemostatic values. CONCLUSIONS: TEG could be used to provide additional information about the haemostatic system in equine neonates.