Characterization of the contributions of Hp-MMP 9 to the serum acute phase protein response of lipopolysaccharide challenged calves

Live-attenuated Japanese encephalitis virus inhibits glioblastoma growth and elicits potent antitumor immunity

Glioblastomas (GBMs) are highly aggressive brain tumors that have developed resistance to currently available conventional therapies, including surgery, radiation, and systemic chemotherapy. In this study, we investigated the safety of a live attenuated Japanese encephalitis vaccine strain (JEV-LAV) virus as an oncolytic virus for intracerebral injection in mice. We infected different GBM cell lines with JEV-LAV to investigate whether it had growth inhibitory effects on GBM cell lines in vitro. We used two models for evaluating the effect of JEV-LAV on GBM growth in mice. We investigated the antitumor immune mechanism of JEV-LAV through flow cytometry and immunohistochemistry. We explored the possibility of combining JEV-LAV with PD-L1 blocking therapy. This work suggested that JEV-LAV had oncolytic activity against GBM tumor cells in vitro and inhibited their growth in vivo. Mechanistically, JEV-LAV increased CD8+ T cell infiltration into tumor tissues and remodeled the immunosuppressive GBM microenvironment that is non-conducive to immunotherapy. Consequently, the results of combining JEV-LAV with immune checkpoint inhibitors indicated that JEV-LAV therapy improved the response of aPD-L1 blockade therapy against GBM. The safety of intracerebrally injected JEV-LAV in animals further supported the clinical use of JEV-LAV for GBM treatment.

Biomarkers of sepsis in pigs, horses and cattle: from acute phase proteins to procalcitonin

Sepsis is a complex clinical syndrome triggered by an inflammatory host response to an infection. It is usually complicated to detect and diagnose, and has severe consequences in human and veterinary health, especially when treatment is not started early. Therefore, efforts to detect sepsis accurately are needed. In addition, its proper diagnosis could reduce the misuse of antibiotics, which is essential fighting against antimicrobial resistance. This case is a particular issue in farm animals, as antibiotics have been traditionally given massively, but now they are becoming increasingly restricted. When sepsis is suspected in animals, the most frequently used biomarkers are acute phase proteins such as C-reactive protein, serum amyloid A and haptoglobin, but their concentrations can increase in other inflammatory conditions. In human patients, the most promising biomarkers to detect sepsis are currently procalcitonin and presepsin, and there is a wide range of other biomarkers under study. However, there is little information on the application of these biomarkers in veterinary species. This review aims to describe the general concepts of sepsis and the current knowledge about the biomarkers of sepsis in pigs, horses, and cattle and to discuss possible advances in the field.

Sequential changes in hepatic mRNA abundance and serum concentration of serum amyloid A in cattle with acute inflammation caused by endotoxin

The objective of the present study was to elucidate sequential changes in mRNA abundance of serum amyloid A (SAA) isotypes in endotoxin (ETX) challenge model cattle. Ten healthy cattle were separated to 2 groups: control and ETX groups. Cattle in the ETX group were challenged by 2.5 µg/kg of O111:B4 lipopolysaccharide in 4 ml of autologous serum. Blood samples were withdrawn at pre, 0.5, 1, 2, 4, 8, 12, 24, 48, 72 and 96 hr after ETX challenge. Plasma ETX activity, serum SAA concentrations, mRNA abundance of interleukin (IL)-6, SAA2 and SAA4 in the liver and polymorphonuclear leukocytes were measured. The plasma ETX activity in the ETX group increased at 0.5 hr after the ETX challenge. The serum SAA value remained higher between 12 and 72 hr after the ETX challenge than that of the control group. Hepatic IL-6 mRNA abundance in the ETX group increased at 2 hr after the ETX challenge. Hepatic SAA2 and SAA4 mRNA abundance significantly increased from 4 hr after administration, and remained significantly higher than those pre-values up to 12 and 24 hr, respectively. The abundance ratio of hepatic SAA2 was much higher than that of SAA4. The major isotype was SAA2 in liver tissue, and it is indicating systemic inflammation in cattle.

Oral administration of lipopolysaccharides from Escherichia coli (serotype O111:B4) does not induce an effective systemic immune response in milk-fed Holstein calves

It is well established that intravenous administration of lipopolysaccharides (LPS)-cell wall components from gram-negative bacteria-induce acute inflammatory responses in dairy calves, but the effect of oral administration of LPS to dairy calves is currently unknown. To evaluate the effects of oral administration of LPS derived from Escherichia coli (serotype O111:B4) on innate immune responses in milk-fed Holstein calves, 20 visually healthy calves (34 ± 1 d) received 4 L of milk with LPS (12 μg/kg body weight; n = 10; LPS) or without LPS (n = 10; control) at the morning feeding. Samples were collected at 0.5 h before the morning feeding and at 3, 6, 24, 48, 72, and 168 h after the morning feeding to measure rectal temperature and heart rate, as well as plasma-negative and plasma-positive acute phase proteins (i.e., haptoglobin, serum amyloid A, albumin, total protein, and fibrinogen) and immunoglobulin concentrations (IgG, IgM, and IgA). None of these measurements was affected by the oral administration of LPS. Oral administration of LPS at 12 μg/kg of body weight did not induce an acute inflammatory response in visually healthy milk-fed Holstein calves when administered in milk.

The effects of pretransportation or arrival meloxicam administration to calves entering the feedlot on morbidity, biomarkers, performance, and carcass characteristics

The objective of this trial was to investigate the effects of using meloxicam as a pretransport or on arrival therapeutic on disease outcomes of bovine respiratory disease (BRD), biomarker outcomes associated with BRD, performance characteristics over the first 42 d on feed, and carcass traits at harvest in cross bred beef cattle. Multisourced, crossbred steer calves (n = 168) consisting of mainly British and British-Continental breeds were purchased from an auction market in central Missouri. Calves were processed prior to transportation and again upon feedlot arrival. Animals were randomized to 3 separate treatments: pretransport meloxicam (PMEL), arrival meloxicam (AMEL), and a control group receiving inactive excipient (CONT). Dosing at 1 mg/kg on weighted averaged administered per os. Animals were weighed and blood was collected pre- and post-transport. Haptoglobin (Hp)-matrix metaloproteinase (MMP)-9 complex, cortisol, and substance P were quantified. Weights were taken again at 42 d and at harvest. Clinical signs of BRD were monitored using indicators of depression, appetite, respiration, and temperature that qualified the animals for treatment. Harvest parameters were collected using a standardized United States Department of Agriculture grading system for quality grade and yield grade. Meloxicam did not have a significant effect on BRD morbidity over the course of the study and there was no significant effect on performance characteristics at 42 d (P > 0.10). Of the calves that did succumb to BRD, no significant differences were found in severity of disease (P > 0.10). Concentrations of substance P and Hp- MMP-9, were increased on arrival (P ≤ 0.05) however no significant treatment effect or interaction were found between AMEL, PMEL, CONT, or across different levels of biomarkers (P > 0.10). Meloxicam use prior to or on arrival does not mitigate disease or improve performance during the feeding period.

The ectoenzyme-side of matrix metalloproteinases (MMPs) makes inflammation by serum amyloid A (SAA) and chemokines go round

During an inflammatory response, a large number of distinct mediators appears in the affected tissues or in the blood circulation. These include acute phase proteins such as serum amyloid A (SAA), cytokines and chemokines and proteolytic enzymes. Although these molecules are generated within a cascade sequence in specific body compartments allowing for independent action, their co-appearance in space and time during acute or chronic inflammation points toward important mutual interactions. Pathogen-associated molecular patterns lead to fast induction of the pro-inflammatory endogenous pyrogens, which are evoking the acute phase response. Interleukin-1, tumor necrosis factor-α and interferons simultaneously trigger different cell types, including leukocytes, endothelial cells and fibroblasts for tissue-specific or systemic production of chemokines and matrix metalloproteinases (MMPs). In addition, SAA induces chemokines and both stimulate secretion of MMPs from multiple cell types. As a consequence, these mediators may cooperate to enhance the inflammatory response. Indeed, SAA synergizes with chemokines to increase chemoattraction of monocytes and granulocytes. On the other hand, MMPs post-translationally modify chemokines and SAA to reduce their activity. Indeed, MMPs internally cleave SAA with loss of its cytokine-inducing and direct chemotactic potential whilst retaining its capacity to synergize with chemokines in leukocyte migration. Finally, MMPs truncate chemokines at their NH₂- or COOH-terminal end, resulting in reduced or enhanced chemotactic activity. Therefore, the complex interactions between chemokines, SAA and MMPs either maintain or dampen the inflammatory response.

Effect of oral administration of meloxicam prior to transport on inflammatory mediators and leukoctye function of cattle at feedlot arrival

OBJECTIVE To investigate the effects of meloxicam administration before long-distance transport on inflammatory mediators and leukocyte function of cattle at feedlot arrival. ANIMALS 60 healthy yearling beef steers. PROCEDURES Single-source steers were assigned to a transported (n = 40) or nontransported (20) group. Then, half of the steers within each group were assigned to receive meloxicam (1 mg/kg, PO) or a lactose placebo (1 bolus/steer, PO). All steers were transported approximately 1,300 km overnight to a feedlot; however, the nontransported group was moved before treatment (meloxicam or placebo) administration and allowed a 17-day acclimation period, whereas the transported group was moved immediately after treatment administration on day -1. Blood samples for measurement of inflammatory mediators and leukocyte function were collected from all steers on days -1, 0, and 3. RESULTS For steers that received meloxicam, mean plasma meloxicam concentration for the transported group was significantly greater than that for the nontransported group on day 0. For steers that received the placebo, mean haptoglobin-matrix metalloproteinase-9 complex for the transported group was significantly greater than that for the nontransported group on day 0. Mean haptoglobin concentration, neutrophil L-selectin intensity, and polymorphonuclear leukocyte count for the transported group were significantly greater than those for the nontransported group. Mean substance P concentration for nontransported steers that received meloxicam was significantly lower than that for the other 3 treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated meloxicam administration to healthy steers immediately before long-distance transport did not significantly mitigate the effects of transport-induced stress on leukocyte function or inflammatory markers.

Serum proteins and lipids in mild form of calf bronchopneumonia: candidates for reliable biomarkers

Calf bronchopneumonia is complex multifactorial disease and for its accurate diagnosis and therapy, besides clinical examination, microbiologic, hematologic and biochemical analyses could be necessary. In general, additional analyses are not implemented, mainly because the disease biomarkers are not defined.

To establish which analysis might be useful for determining the severity of the disease, we analyzed 23 three-month old calves with mild clinical signs of bronchopneumonia and 15 age-matched healthy calves. Pasteurella multocida was isolated from deep nasal swabs of diseased calves. Peripheral blood erythrocyte and leukocyte count of bronchopneumonic and healthy calves showed no difference. Serum proteins, lipoproteins and lipids were analyzed with spectrophotometry, agarose gel electrophoresis, non-reducing SDS-PAGE, gel zymography, and thin-layer chromatography. The bronchopneumonic calves had an increased level of circulating immune complexes and α globulins, which contain some of the positive acute phase proteins. In diseased calves the increased concentration of total γ globulins (IgG), due to an increased concentration of anionic γ globulins (predominately IgG1), was detected. The increased concentration of anionic γ globulins followed by increased concentration of transferrin (negative acute phase protein) and HDL cholesterol, decreased concentration of LDL-cholesterol, unchanged activity of matrix metalloproteases and leukocyte counts might reflect the obvious absence of generalized inflammation. A positive correlation was found between the acquired results and the appearance of mild clinical signs. Therefore, we believe that the parameters analyzed in the peripheral blood could be applied as reliable disease markers to distinguish between severe (inflammatory) and mild forms of calf bronchopneumonia and to predict a better outcome for these calves.