Widespread expression of SAA and Hp RNA in bovine tissues after evaluation of suitable reference genes

Measurement of Feline Alpha-1 Acid Glycoprotein in Serum and Effusion Using an ELISA Method: Analytical Validation and Diagnostic Role for Feline Infectious Peritonitis

BACKGROUND

Alpha-1 acid glycoprotein (AGP) may support a clinical diagnosis of feline infectious peritonitis (FIP). In this study, we assessed the analytical and diagnostic performances of a novel ELISA method to measure feline AGP.

METHODS

AGP was measured in sera and effusions from cats with FIP (n = 20) or with other diseases (n = 15). Precision was calculated based on the coefficient of variation (CV) of repeated testing, and accuracy was calculated by linearity under dilution (LUD).

RESULTS

The test is precise (intra-assay CVs: <6.0% in individual samples, <15.0% in pooled samples; inter-assay CVs <11.0% and <15.0%) and accurate (serum LUD r2: 0.995; effusion LUD r2: 0.950) in serum and in effusions. AGP is higher in cats with FIP than in other cats in both serum (median: 1968, I-III interquartile range: 1216-3371 μg/mL and 296, 246-1963 μg/mL; p = 0.009) and effusion (1717, 1011-2379 μg/mL and 233, 165-566 μg/mL; p < 0.001). AGP discriminates FIP from other diseases (area under the receiver operating characteristic curve: serum, 0.760; effusion, 0.877), and its likelihood ratio is high (serum: 8.50 if AGP > 1590 μg/mL; effusion: 3.75 if AGP > 3780 μg/mL).

CONCLUSION

This ELISA method is precise and accurate. AGP in serum and in effusions is a useful diagnostic marker for FIP.

Acute phase reaction to lipopolysaccharide-induced mastitis in early lactation dairy cows fed nitrogenic, glucogenic, or lipogenic diets

The availability of certain macronutrients is likely to influence the capacity of the immune system. Therefore, we investigated the acute phase response to intramammary (i.mam.) lipopolysaccharide (LPS) in dairy cows fed a nitrogenic diet (n = 10) high in crude protein, a glucogenic diet (n = 11) high in carbohydrates and glucogenic precursors, or a lipogenic diet (n = 11) high in lipids. Thirty-two dairy cows were fed one of the dietary concentrates directly after calving until the end of trial at 27 ± 3 days in milk (mean ± standard deviation). In wk 3 of lactation, 20 µg of LPS was i.mam. injected in one quarter, and sterile NaCl (0.9%) in the contralateral quarter. Milk samples of the LPS-challenged and control quarter were taken hourly from before (0 h) until 9 h after LPS challenge and analyzed for milk amyloid A (MAA), haptoglobin (HP), and IL-8. In addition, blood samples were taken in the morning, and composite milk samples at morning and evening milkings, from 1 d before until 3 d after LPS challenge, and again on d 9, to determine serum amyloid A (SAA) and HP in blood, and MAA and HP in milk. The mRNA abundance of various immunological and metabolic factors in blood leukocytes was quantified by quantitative reverse-transcription PCR from samples taken at -18, -1, 6, 9, and 23 h relative to LPS application. The dietary concentrates did not affect any of the parameters in blood, milk, and leukocytes. The IL-8 was increased from 2 h, HP from 2 to 3 h, and MAA from 6 h relative to the LPS administration in the milk of the challenged quarter and remained elevated until 9 h. The MAA and HP were also increased at 9 h after LPS challenge in whole-udder composite milk, whereas HP and SAA in blood were increased only after 23 h. All 4 parameters were decreased again on d 9. Similar for all groups, the mRNA abundance of HP and the heat shock protein family A increased after the LPS challenge, whereas the mRNA expression of the tumor necrosis factor α and the leukocyte integrin β 2 subunit (CD18) were decreased at 6 h after LPS challenge. The glucose transporter (GLUT)1 mRNA abundance decreased after LPS, whereas that of the GLUT3 increased, and that of the GLUT4 was not detectable. The mRNA abundance of GAPDH was increased at 9 h after LPS and remained elevated. The acute phase protein response was detected earlier in milk compared with blood indicating mammary production. However, immunological responses to LPS were not affected by the availability of specific macronutrients provided by the different diets.

Effects of adding ruminal propionate on dry matter intake and glucose metabolism in steers fed a finishing ration

The objective of this experiment was to determine if supplying additional propionate to the rumen alters dry matter intake (DMI), feeding behavior, glucose metabolism, and rumen fluid metabolites in steers fed a finishing diet. Ruminally cannulated steers (n = 6) were fed a finishing diet ad libitum. Steers were randomly assigned to one of three treatments in a 3 × 6 Latin rectangle design with three 15 d periods. Treatments of no Ca propionate (Control), 100 g/d (Low), or 300 g/d (High) were ruminally dosed twice daily. Individual intake was measured using an Insentec feeding system. Pre-feeding blood samples were collected on day 7 and rumen fluid samples were collected on day 13. An intravenous glucose tolerance test (IVGTT) was conducted on day 14 and liver biopsies were collected on day 15. Liver samples were analyzed for expression of genes involved in gluconeogenesis. Data were analyzed using a mixed model with period, treatment, day, and their interaction included, with day and minute within period as a repeated measure and steer as a random effect. Meal size (P = 0.049), meal frequency (P = 0.046), and DMI (P < 0.001) were decreased in High steers. Day 7 plasma glucose (P = 0.23) and lactate (P = 0.47) were not affected by treatment, but insulin was decreased (P = 0.008) and non-esterified fatty acids were increased (P = 0.044) in the High treatment compared with the Control. Rumen fluid lactate was decreased (P = 0.015) in the High treatment compared with the Low treatment. Total VFA concentrations did not differ (P = 0.88) between treatments. There was treatment × time interaction for proportions of acetate and propionate (P < 0.001) and the acetate:propionate ratio (P = 0.005). The effect on acetate was due to a decrease in the High treatment 2 h after dosing the treatment. Propionate proportions were greater in the High treatment than the Control at all time points and differed from the Low except at 0 h. Propionate treatments had no major effects on the glucose and insulin parameters observed in the IVGTT other than a tendency (P = 0.09) for an increased insulin time to peak. These data indicate that exogenous propionate decreases DMI but the decrease in propionate from fermentation due to reduced DMI might negate the supply of exogenous propionate in VFA supply to the animal. Mechanisms other than hepatic oxidation of propionate might be responsible for DMI regulation.

Adaptive Cell-Mediated Immunity in the Mammary Gland of Dairy Ruminants

Mastitis is one of the greatest issues for the global dairy industry and controlling these infections by vaccination is a long-sought ambition that has remained unfulfilled so far. In fact, gaps in knowledge of cell-mediated immunity in the mammary gland (MG) have hampered progress in the rational design of immunization strategies targeting this organ, as current mastitis vaccines are unable to elicit a strong protective immunity. The objectives of this article are, from a comprehensive and critical review of available literature, to identify what characterizes adaptive immunity in the MG of ruminants, and to derive from this analysis research directions for the design of an optimal vaccination strategy. A peculiarity of the MG of ruminants is that it does not belong to the common mucosal immune system that links the gut immune system to the MG of rodents, swine or humans. Indeed, the MG of ruminants is not seeded by lymphocytes educated in mucosal epithelia of the digestive or respiratory tracts, because the mammary tissue does not express the vascular addressins and chemokines that would allow the homing of memory T cells. However, it is possible to elicit an adaptive immune response in the MG of ruminants by local immunization because the mammary tissue is provided with antigen-presenting cells and is linked to systemic mechanisms. The optimal immune response is obtained by luminal exposure to antigens in a non-lactating MG. The mammary gland can be sensitized to antigens so that a local recall elicits neutrophilic inflammation and enhanced defenses locally, resulting from the activation of resident memory lymphocytes producing IFN-γ and/or IL-17 in the mammary tissue. The rational exploitation of this immunity by vaccination will need a better understanding of MG cell-mediated immunity. The phenotypic and functional characterization of mammary antigen-presenting cells and memory T cells are amongst research priorities. Based on current knowledge, rekindling research on the immune cells that populate the healthy, infected, or immunized MG appears to be a most promising approach to designing efficacious mastitis vaccines.

Changes in social and feeding behaviors, activity, and salivary serum amyloid A in cows with subclinical mastitis

The aim of this study was to identify detailed changes in behavior, and in salivary serum amyloid A (SAA), associated with subclinical mastitis. This included standard sickness behaviors, such as decreased activity, feeding and drinking (here labeled "core maintenance" behaviors), and less well-studied social, grooming, and exploratory behaviors (here labeled "luxury" behaviors). Luxury behaviors are biologically predicted to change at lower levels of mastitis infection and are, therefore, particularly relevant to detecting subclinical mastitis. Salivary serum amyloid A is a physiological marker of systemic inflammation, with levels in milk and serum already known to increase during subclinical mastitis. We investigated whether the same was true for SAA in cow saliva. Data were collected for 17 matched pairs of commercial barn-housed Holstein-Friesian cows. Each pair comprised a cow with subclinical mastitis (SCM) and a healthy control (CTRL), identified using somatic cell count (SCC; SCM: SCC >200 × 1,000 cells/mL; CTRL: SCC <100 × 1,000 cells/mL). SCM cows were selected for study ad hoc, at which point they were paired with a CTRL cow, based upon parity and calving date; consequently, the full data set was accrued over several months. Data were collected for each pair over 3 d: SCC (d 1), behavior (d 2), salivary SAA (d 3). All behaviors performed by the focal cows over a single 24-h period were coded retrospectively from video footage, and differences between the SCM and CTRL groups were investigated using the main data set and a subset of data corresponding to the hour immediately following morning food delivery. Saliva was collected using cotton swabs and analyzed for SAA using commercially available ELISA kits. We report, for the first time, that an increase in salivary SAA occurs during subclinical mastitis; SAA was higher in SCM cows and demonstrated a positive (weak) correlation with SCC. The behavioral comparisons revealed that SCM cows displayed reductions in activity (behavioral transitions and distance moved), social exploration, social reactivity (here: likelihood to be displaced following receipt of agonism), performance of social grooming and head butts, and the receipt of agonistic noncontact challenges. In addition, SCM cows received more head swipes, and spent a greater proportion of time lying with their head on their flank than CTRL cows. The SCM cows also displayed an altered feeding pattern; they spent a greater proportion of feeding time in direct contact with 2 conspecifics, and a lower proportion of feeding time at self-locking feed barriers, than CTRL cows. Behavioral measures were found to correlate, albeit loosely, with serum SAA in a direction consistent with predictions for sickness behavior. These included positive correlations with lying duration and the receipt of all agonistic behavior, and negative correlations with feeding, drinking, the performance of all social and all agonistic behavior, and social reactivity. We conclude that changes in salivary SAA, social behavior, and activity offer potential in the detection of subclinical mastitis and recommend further investigation to substantiate and refine our findings.

Invited review: The influence of immune activation on transition cow health and performance-A critical evaluation of traditional dogmas

The progression from gestation into lactation represents the transition period, and it is accompanied by marked physiological, metabolic, and inflammatory adjustments. The entire lactation and a cow's opportunity to have an additional lactation are heavily dependent on how successfully she adapts during the periparturient period. Additionally, a disproportionate amount of health care and culling occurs early following parturition. Thus, lactation maladaptation has been a heavily researched area of dairy science for more than 50 yr. It was traditionally thought that excessive adipose tissue mobilization in large part dictated transition period success. Further, the magnitude of hypocalcemia has also been assumed to partly control whether a cow effectively navigates the first few months of lactation. The canon became that adipose tissue released nonesterified fatty acids (NEFA) and the resulting hepatic-derived ketones coupled with hypocalcemia lead to immune suppression, which is responsible for transition disorders (e.g., mastitis, metritis, retained placenta, poor fertility). In other words, the dogma evolved that these metabolites and hypocalcemia were causal to transition cow problems and that large efforts should be enlisted to prevent increased NEFA, hyperketonemia, and subclinical hypocalcemia. However, despite intensive academic and industry focus, the periparturient period remains a large hurdle to animal welfare, farm profitability, and dairy sustainability. Thus, it stands to reason that there are alternative explanations to periparturient failures. Recently, it has become firmly established that immune activation and the ipso facto inflammatory response are a normal component of transition cow biology. The origin of immune activation likely stems from the mammary gland, tissue trauma during parturition, and the gastrointestinal tract. If inflammation becomes pathological, it reduces feed intake and causes hypocalcemia. Our tenet is that immune system utilization of glucose and its induction of hypophagia are responsible for the extensive increase in NEFA and ketones, and this explains why they (and the severity of hypocalcemia) are correlated with poor health, production, and reproduction outcomes. In this review, we argue that changes in circulating NEFA, ketones, and calcium are simply reflective of either (1) normal homeorhetic adjustments that healthy, high-producing cows use to prioritize milk synthesis or (2) the consequence of immune activation and its sequelae.

Serum amyloid A, Serum Amyloid A1 and Haptoglobin in pregnant mares and their fetuses after experimental induction of placentitis

Serum amyloid A (SAA) and Haptoglobin (Hp) are acute phase proteins, produced during inflammation, such as placentitis. In horses, SAA and SAA1 are protein coding genes. Objectives were to analyze SAA and Hp concentrations and relative abundance of SAA, SAA1 and Hp mRNA transcript in maternal and fetal tissues after experimental induction of placentitis or mares of a control group. Serum Amyloid A family proteins were in marked abundance in the stroma of the endometrium and chorioallantois associated with inflammatory cells. Maternal plasma SAA concentrations were greater (P = 0.01) in mares with experimentally induced placentitis compared to those of the control group. Maternal Hp from the groups were not different, but fetal Hp concentrations of mares with experimentally induced placentitis were greater (P = 0.02). Maternal plasma SAA and Hp concentrations were greater than fetal plasma concentrations in mares with experimentally induced placentitis (P < 0.05). Relative abundance of SAA mRNA transcript was greater in the maternal, fetal liver and chorioallantois of mares with experimentally induced placentitis (P < 0.05) compared to those in the control group. Interestingly, relative abundance of SAA1 mRNA transcript was greater in the chorioallantois of mares with experimentally induced placentitis (P < 0.05). The SAA and Hp concentrations, therefore, were greater in mares with induced placentitis. Furthermore, relative abundance of SAA1 mRNA transcript is specifically greater in the chorioallantois of mares with placentitis, which warrants further studies to elucidate the immunological response of SAA1 in the chorioallantois of mares with placentitis.

Methods in isolation and characterization of bovine monocytes and macrophages

Monocytes and macrophages belong to the mononuclear phagocyte system and play important roles in both physiological and pathological processes. The cells belonging to the monocyte/macrophage system are structurally and functionally heterogeneous. Several subsets of monocytes have been previously identified in mammalian blood, generating different subpopulations of macrophages in tissues. Although their distribution and phenotype are similar to their human counterpart, bovine monocytes and macrophages feature differences in both functions and purification procedures. The specific roles that monocytes and macrophages fulfil in several important diseases of bovine species, including among the others tuberculosis and paratuberculosis, brucellosis or the disease related to peripartum, remain still partially elusive. The purpose of this review is to discuss the current knowledge of bovine monocytes and macrophages. We will describe methods for their purification and characterization of their major functions, including chemotaxis, phagocytosis and killing, oxidative burst, apoptosis and necrosis. An overview of the flow cytometry and morphological procedures, including cytology, histology and immunohistochemistry, that are currently utilized to describe monocyte and macrophage main populations and functions is presented as well.

Putative biomarkers for early detection of mastitis in cattle

Context Mastitis is an inflammation of mammary gland parenchyma, and is an unending cause of economic loss to the dairy industry. The interest in research on biomarker discovery for the diagnosis of bovine mastitis stems largely from the need to identify reliable biomarkers. Aim To determine the putative biomarkers of mastitis by using bioinformatics analysis, and experimental validation of pro-inflammatory cytokines and oxidative stress biomarkers of the mammary gland in healthy and diseased animals. Methods Various in silico analysis tools were applied to screen for gene expression in mastitis. Milk, as well as blood samples, was collected aseptically from the animals, which were then classified into three groups; namely, clinical, subclinical and control. Samples were subjected to assay of pro-inflammatory cytokines and oxidative biomarkers using enzyme-linked immunosorbent assay kits and the prescribed methodology respectively. Key results In silico analysis revealed that mastitis reduces the expression of fat metabolism and immune system-related genes, whereas it increased the expression of inflammatory genes. On laboratory analysis of cytokines and acute phase protein, it was revealed that interleukin-1∝, interleukin-8 and haptoglobin were significantly (P &lt; 0.01) increased in both blood serum and milk whey in subclinical and clinical mastitis cows. On analysis of oxidative biomarkers, our results showed that oxidative stress was significantly (P &lt; 0.05) increased with progression of mastitis in dairy cows. There was a significant (P &lt; 0.05) increase in the blood serum level of malondialdehyde and nitric oxide, and a decrease in the level of anti-oxidant enzymes – glutathione peroxidase, superoxide dismutase and catalase – compared with healthy animals. Conclusion In conclusion, bioinformatics analysis of high-throughput gene expression revealed the involvement of multiple pathways, including the inflammatory pathway, fatty acid pathway and triglyceride synthesis pathway, in mastitis. Experimental validation confirmed that interleukin-8 and haptoglobin are putative early diagnostic markers for mastitis in dairy cattle. This study also concluded that milk can be used for the detection of cytokines as a non-invasive technique.

Identification of Gene Changes Induced by Dexamethasone in the Anterior Segment of the Human Eye Using Bioinformatics Analysis

BACKGROUND Glucocorticoids (GCs)-induced glaucoma is a common adverse effect of prolonged GCs use. To better understand the effects of GCs on aqueous humor (AH) outflow, we analyzed the dataset GSE37474 using bioinformatics analysis to identify gene changes and pathways in the anterior segment of the human eye induced by dexamethasone (DEX). MATERIAL AND METHODS The GSE37474 dataset downloaded from the Gene Expression Omnibus (GEO) database was examined in this study. GEO2R was utilized to analyze data and identify differentially expressed genes (DEGs). Gene Ontology (GO) enrichment and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were constructed using the DAVID database followed by construction of a protein-protein interaction (PPI) network performed using Cytoscape software. Finally, modules and hub genes were screened out using MCODE and cytoHubba plugin, respectively. RESULTS A set of 252 DEGs were screened. Among the DEGs, 143 genes were upregulated and 109 were downregulated. GO analysis indicated that some of the DEGs participated in extracellular matrix (ECM) organization and cholesterol homeostasis. Additionally, KEGG pathways were predominantly enriched in tyrosine metabolism and ECM-receptor interaction. From the PPI network, 2 modules were identified, and 10 hub genes were screened out, including CCL2, FOS, IGF1, PTGS2, CCL5, EDN1, IL11, F3, PMCH, and BDKRB1. The 2 module genes primarily participate in the TNF signaling pathway, cytokine-cytokine receptor interaction, and the Jak-STAT signaling pathway. CONCLUSIONS The present study identified some significant DEGs, hub genes, pathways, and modules in the human anterior segment induced by DEX. These results demonstrate that DEX changes the expression of certain genes and pathways to resist aqueous humor outflow, which could be new targets for developing novel and more effective approaches of diagnosis and therapy for GCs-induced glaucoma.

Endometrial expression of the acute phase molecule SAA is more significant than HP in reflecting the severity of endometritis

This study investigated the correlation between endometrial local expressions of serum amyloid A (SAA) and haptoglobin (Hp) and severity of endometritis in 20 Chinese Holstein dairy cows at 40-60 days postpertum, aged 3-6, and 2-5 parities. Endometrial biopsies were collected and categorized into normal, mild endometritis, and severe endometritis based on clinical signs and histopathology. The protein and mRNA expression of SAA and Hp in endometrial tissue were measured using western blot and real-time PCR, respectively. Furthermore, bovine endometrial epithelial cells were isolated and cultured in vitro. The protein and mRNA expression of SAA and Hp were also determined in the cells treated with increasing concentrations of lipopolysaccharide (LPS; 0, 1, 5, 10 μg/ml). The results showed that both of protein and mRNA of SAA was increased in endometritis or in LPS-stimulated cells, and the increases were positively correlated with severity of endometritis in vivo or LPS stimulation strength in vitro. Meanwhile, protein expression of Hp were also increased in endometritis or in LPS-stimulated cells, but the increases were negatively correlative with severity of inflammation as well as mRNA expression of Hp in vivo or in vitro. Therefore, our results suggest that endometrial local expression of SAA is more significant than Hp as a potential biomarker to assess severity of endometritis in cows.

Tolerance and Innate Immunity Shape the Development of Postpartum Uterine Disease and the Impact of Endometritis in Dairy Cattle

Bacteria are ubiquitous in the bovine uterus after parturition, but 50 years ago, cows tolerated these bacteria and few animals developed uterine disease. Now, up to 40% of dairy cattle develop postpartum uterine disease. Uterine disease causes infertility by compromising the function of not only the endometrium but also the ovary. Animals defend themselves against pathogens using tolerance and resistance mechanisms. Tolerance is the ability to limit the disease severity induced by a given pathogen burden. Resistance is the ability to limit the pathogen burden and is usually the function of immunity. Endometrial cells contribute to tolerance and have roles in innate immunity and the inflammatory response to pathogens. However, failures in endometrial tolerance and the character of the inflammatory response shape postpartum uterine disease. We propose that uterine health is more dependent on the ability of the endometrium to tolerate pathogens than the ability to resist invading bacteria.

Widespread extrahepatic expression of acute-phase proteins in healthy chicken (Gallus gallus) tissues

Acute phase proteins (APP) are plasma proteins that can modify their expression in response to inflammation caused by tissue injury, infections, immunological disorders or stress. Although APP are produced mainly in liver, extrahepatic production has also been described. As a prerequisite to get insight the expression of APP in chicken during diseases, this study investigated the presence of five APP, including alpha1-acid glycoprotein (AGP), Serum Amyloid A (SAA), PIT54, C-Reactive protein (CRP) and Ovotransferrin (OVT) in twenty tissues collected from healthy chicken (Gallus gallus) by quantitative Real Time PCR and immunohistochemistry. As expected, APP gene abundance was higher in liver compared with other tissues. The mRNA coding for CRP, OVT and SAA was detected in all analyzed tissues with a higher expression in gastrointestinal tract, respiratory and lymphatic samples. SAA expression was particularly high in cecal tonsil, lung, spleen and Meckel's diverticulum, whereas OVT in lung, bursa of Fabricius and pancreas. AGP and PIT54 mRNA expression were detected in all tissues but at negligible levels. Immunohistochemical expression of AGP and OVT was variably detected in different organs, being identified in endothelium of every tissue. Positive cells were present in the epithelium of the mucosal layer of gastrointestinal tract and kidney. Lung and central nervous system stained for both proteins. No positive staining was detected in lymphoid tissues and muscle. These results suggest that most tissues can express different amount of APP even in healthy conditions and are therefore capable to mount a local acute phase reaction.

Stable reference genes in granulosa cells of bovine dominant follicles during follicular growth, FSH stimulation and maternal aging

The aim of the present study was to determine a set of reference genes in granulosa cells of dominant follicles that are suitable for relative gene expression analyses during maternal and follicular aging. Granulosa cells of growing and preovulatory dominant follicles were collected from aged and young cows (maternal aging study) and from FSH-stimulated follicles developing under different durations of FSH treatment (follicular aging study). The mRNA levels of the two commonly used reference genes (GAPDH, ACTB) and four novel genes (UBE2D2, EIF2B2, SF3A1, RNF20) were analysed using cycle threshold values. Results revealed that mRNA levels of GAPDH, ACTB, EIF2B2, RNF20, SF3A1 and UBE2D2 were similar (P>0.05) between dominant follicle type, age and among follicles obtained after FSH-stimulation, but differed (P=0.005) due to mRNA processing (i.e. with versus without amplification). The stability of reference genes was analysed using GeNorm, DeltaCT and NormFinder programs and comprehensive ranking order was determined using RefFinder. The mRNA levels of GAPDH and ACTB were less stable than those of UBE2D2 and EIF2B2. The geometric mean of multiple genes (UBE2D2, EIF2B2, GAPDH and SF3A1) is a more appropriate reference control than the use of a single reference gene to compare relative gene expression among dominant and FSH-stimulated follicles during maternal and/or follicular aging studies.

Molecular Characterization of Buffalo Haptoglobin: Sequence Based Structural Comparison Indicates Convergent Evolution Between Ruminants and Human

Haptoglobin (Hp) protein has high affinity for hemoglobin (Hb) binding during intravascular hemolysis and scavenges the hemoglobin induced free radicals. Earlier reports indicate about uniqueness of Hp molecule in human and cattle, but in other animals, it is not much studied. In this paper, we characterized buffalo Hp molecule and determined its molecular structure, evolutionary importance, and tissue expression. Comparative analysis and predicted domain structure indicated that the buffalo Hp has an internal duplicated region in α-chain only similar to an alternate Hp2 allele in human. This duplicated part encoded for an extra complement control protein CCP domain. Phylogenetic analysis revealed that buffalo and other ruminants were found to group together separated from all other non-ruminants, including human. The key amino acid residues involved in Hp and Hb as well as Hp and macrophage scavenger receptor, CD163 interactions in buffalo, depicted a significant variation in comparison to other non-ruminant species. Constitutive expression of Hp was also confirmed across all the vital tissues of buffalo, for the first time. Results revealed that buffalo Hp is both structurally and functionally conserved, having internal duplication in α-chain similar to human Hp2 and other ruminant species, which might have evolved separately as a convergent evolutionary process. Furthermore, the presence of extra Hp CCP domain possibly in all ruminants may have an effect during dimerization of molecule in these species.

Acute phase proteins as promising biomarkers: Perspectives and limitations for human and veterinary medicine

Acute phase proteins (APPs) are highly conserved plasma proteins that are increasingly secreted by the liver in response to a variety of injuries, independently of their location and cause. APPs favor the systemic regulation of defense, coagulation, proteolysis, and tissue repair. Various APPs have been applied as general diagnostic parameters for a long time. Through proteomic techniques, more and more APPs have been discovered to be differentially altered. Since they are not consistently explainable by a stereotypic hepatic expression of sets of APPs, most of these results have unfortunately been neglected or attributed to the nonspecificity of the acute phase reaction. Moreover, it appears that various extrahepatic tissues are also able to express APPs. These extrahepatic APPs show focally specific roles in tissue homeostasis and repair and are released primarily into interstitial and distal fluids. Since these focal proteins might leak into the circulatory system, mixtures of hepatic and extrahepatic APP species can be expected in blood. Hence, a selective alteration of parts of APPs might be expected. There are several hints on multiple molecular forms and fragments of tissue-derived APPs. These differences offer the chance for multiple selective determinations. Thus, specific proteoforms might indeed serve as tissue-specific disease indicators.

The effect of transport stress on turkey (Meleagris gallopavo) liver acute phase proteins gene expression

The aim of this study was to investigate the effects of transport-related stress on the liver gene expression of four acute phase proteins (APP), namely α1-acid glycoprotein (AGP), C-Reactive Protein (CRP), Serum Amyloid A (SAA) and PIT54, in turkeys (Meleagris gallopavo). A group of seven BUT BIG 6 commercial hens was subjected to a two-hour long road transportation and the quantitative gene expression of APP in the liver was compared to that of a non transported control group. The expression of AGP and CRP mRNA was found to be increased in animals slaughtered after road transport. The presence of AGP protein was also confirmed by immunohistochemistry and Western blotting. The results of this study showed that road-transport may induce the mRNA expression of immune related proteins. The finding that AGP and CRP can be upregulated during transport could suggest their use as for the assessment of turkey welfare during transport.

The localization and differential expression of Serum Amyloid A in bovine liver and adipose tissue depots

In this article the localization of the acute phase protein Serum Amyloid A (SAA) in different depots of bovine adipose tissue (AT) and liver is reported. Quantitative (Real Time) PCR was paired to immunohistochemistry after the production of a specific polyclonal antibody. SAA's mRNA was found in all analyzed AT depots included in the present study, the AT located in the withers being the major source of SAA mRNA. A polyclonal antibody was raised against bovine SAA and was used to validate gene expression analyses. Western Blotting confirmed that SAA is present in all the seven adipose tissue depots include in the present experiment. Anti-SAA polyclonal antibody also stained diffusely adipocytes. In liver, intracytoplasmic immunolabeling was observed in hepatocytes. Staining was generally mild and not diffuse: negative hepatocytes were intermixed with positive ones. A positive intracytoplasmic immunostaining was occasionally observed in endothelial cells lining small blood vessels within AT septa and liver parenchyma. Our data confirm that bovine AT may provide an important source of SAA in healthy subjects. It remains to be determined which is the contribution of AT in the serum concentration of SAA.

The major acute phase proteins of bovine milk in a commercial dairy herd

Background

Milk acute phase proteins (APP) have been identified and show promise as biomarkers of mastitis. However analysis of their profile in dairy cows from a production herd is necessary in order to confirm their benefits in mastitis diagnosis. The profiles of milk haptoglobin (Hp), mammary associated serum amyloid A3 (M-SAA3) and C-reactive protein (CRP) were determined in 54 composite milk (milk from all functional quarters of a cow’s udder collected in a common receptacle) samples (CMS) from a commercial dairy farm. Milk Hp was also determined in individual quarter milk (milk from a single udder quarter) samples (QMS) (n = 149) of the cows.

An ELISA was developed and validated for the determination of milk Hp while commercial kits were used for M-SAA3 and CRP assay respectively. Composite milk APP results were compared with cow factors including parity, stage of lactation, percentage protein and fat as well as somatic cell counts (SCC).

Results

Composite milk Hp ranged from <0.4–55 μg/ml with a median of 3.5 μg/ml; composite milk M-SAA3 ranged from <0.6–50 μg/ml and had a median of 1.2 μg/ml, while CRP ranged from <1.80–173 ng/ml and had a median of 24.6 ng/ml. Significant correlations were found between composite SCC and Hp (P-value <0.009) as well as parity and Hp (P < 0.009), but not between M-SAA3 and SCC, M-SAA3 and Hp, M-SAA3 and CRP or M-SAA3 and parity. Milk CRP was correlated with % fat (P = 0.002) and % protein (P = 0.001) of the milk samples. The lack of correlation of SCC with the M-SAA3 and CRP could result from these APP being more sensitive to intra-mammary infection than SCC. Quarter milk Hp had a range of <0.4–420 μg/ml with a median value of 3.6 μg/ml, with 92 % of samples below 20 μg/ml.

Conclusion

Baseline values of Hp, M-SAA3 and CRP were established in composite milk from cows with normal SCC on the dairy farm. Parity was recognized as a possible confounding factor when diagnosing mastitis using Hp. The value of the APP, Hp, M-SAA3 and CRP as substitutes or to complement SCC in indicating udder inflammation, was demonstrated.

Acute phase proteins as local biomarkers of respiratory infection in calves

Background

Cumulating reports suggest that acute phase proteins (APPs) do not only play a role as systemic inflammatory mediators, but are also expressed in different tissues as local reaction to inflammatory stimuli. The present study aimed to evaluate presence and changes in luminal lung concentrations of the APPs haptoglobin (Hp), lipopolysaccharide binding protein (LBP), C-reactive protein (CRP), and lactoferrin (Lf) in calves with an acute respiratory disease experimentally induced by Chlamydia (C.) psittaci.

Results

Intra-bronchial inoculation of the pathogen resulted in a consistent respiratory illness. In venous blood of the infected calves (n = 13), concentrations of plasma proteins and serum LBP were assessed (i) before exposure and (ii) 8 times within 14 days after inoculation (dpi). Increasing clinical illness correlated significantly with increasing LBP—and decreasing albumin concentrations in blood, both verifying a systemic acute phase response.

Broncho-alveolar lavage fluid (BALF) was obtained from all 13 calves experimentally infected with C. psittaci at 4, 9 and 14 dpi, and from 6 uninfected healthy calves. Concentrations of bovine serum albumin (BSA), Hp, LBP, CRP and Lf in BALF were determined by ELISA. In infected animals, absolute concentrations of LBP and Hp in BALF correlated significantly with the respiratory score. The quotient [LBP]/[BSA] in BALF peaked significantly in acutely infected animals (4 dpi), showed a time-dependent decrease during the recovery phase (9-14 dpi), and was significantly higher compared to healthy controls. Concentrations of Hp and Lf in BALF as well as [Hp]/[BSA]—and [Lf]/[BSA]-quotients decreased during the study in infected animals, but were never higher than in healthy controls. CRP concentrations and [CRP]/[BSA]-quotient did not express significant differences between infected and healthy animals or during the course of infection.

Conclusion

In conclusion, absolute concentrations of LBP in blood and BALF as well as the quotient [LBP]/[BSA] in BALF perfectly paralleled the clinical course of respiratory illness after infection. Beside LBP, the suitability of Hp and Lf as local biomarkers of respiratory infections in cattle and their role in the local response to pathogens is worth further investigation, while CRP does not seem to play a role in local defense mechanisms of the bovine lung.

Genes and environmental factors that influence disease resistance to microbes in the female reproductive tract of dairy cattle

Microbes commonly infect the female reproductive tract of cattle, causing infertility, abortion and post partum uterine diseases. When organisms reach the uterus, the resistance to disease depends on the balance between the classic triad of the virulence of the microbes, the host defence systems and the environment. The present review considers each aspect of this triad, using postpartum uterine disease as an exemplar for understanding disease resistance. The bacteria that cause postpartum uterine disease are adapted to the endometrium, and their microbial toxins cause tissue damage and inflammation. However, non-specific defence systems counter ascending infections of the female reproductive tract, and inflammatory responses in the endometrium are driven by innate immunity. Disease resistance to bacterial infection involves many genes involved in the maintenance or restoration of tissue homeostasis in the endometrium, including antimicrobial peptides, complement, cytokines, chemokines and Toll-like receptors. The most important environmental factors facilitating the development of postpartum uterine disease are related to trauma of the reproductive tract and to the metabolic stress of lactation in dairy cows. Long-term solutions for uterine disease will include genetic selection for disease resistance and optimising the care of the animal before, during and after parturition.

Innate immunity and inflammation of the bovine female reproductive tract in health and disease

Mammalian reproductive physiology and the development of viviparity co-evolved with inflammation and immunity over millennia. Many inflammatory mediators contribute to paracrine and endocrine signalling, and the maintenance of tissue homeostasis in the female reproductive tract. However, inflammation is also a feature of microbial infections of the reproductive tract. Bacteria and viruses commonly cause endometritis, perturb ovarian follicle development and suppress the endocrine activity of the hypothalamus and pituitary in cattle. Innate immunity is an evolutionary ancient system that orchestrates host cell inflammatory responses aimed at eliminating pathogens and repairing damaged tissue. Pattern recognition receptors on host cells bind pathogen-associated molecular patterns and damage-associated molecular patterns, leading to the activation of intracellular MAPK and NFκB signalling pathways and the release of inflammatory mediators. Inflammatory mediators typically include the interleukin cytokines IL1β and IL6, chemokines such as IL8, interferons and prostaglandins. This review outlines the mechanisms of inflammation and innate immunity in the bovine female reproductive tract during health and disease condition.

Validation of reference genes for normalization gene expression in reverse transcription quantitative PCR in human normal thyroid and goiter tissue

Reverse transcription quantitative polymerase chain reaction (RT-qPCR) has been recognized as the most accurate method for quantifying mRNA transcripts, but normalization of samples is a prerequisite for correct data interpretation. So, this study aimed to evaluate the most stable reference gene for RT-qPCR in human normal thyroid and goiter tissues. Beta-actin (ACTB); glyceraldehyde-3-phosphate dehydrogenase (GAPDH); succinate dehydrogenase, subunit A, flavoprotein (Fp) (SDHA); hypoxanthine phosphoribosyltransferase I (HPRTI); tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein, zeta polypeptide (YWHAZ); and beta-2-microglobulin (B2M) were evaluated in 14 thyroid tissue samples (7 normal and 7 goiter tissues) by RT-qPCR. The mean Cq and the maximum fold change (MFC) and NormFinder software were used to assess the stability of the genes. As a result, ACTB gene was more stable than GAPDH, SDHA, HPRTI, YWHAZ, and B2M. In conclusion, ACTB could be used to normalize RT-qPCR data in normal thyroid and goiter tissues.

Effects of feeding various dosages of Saccharomyces cerevisiae fermentation product in transition dairy cows

Feeding 56 versus 0 g/d of Saccharomyces cerevisiae fermentation product (SCFP; Diamond V Original XP; Diamond V, Cedar Rapids, IA) can increase feed intake and milk production in transition dairy cows. To evaluate the effects of various dosages of SCFP, Holstein cows were given individually a supplement containing 0 (n=14), 56 (n=15), or 112 g (n=13) of SCFP daily during morning lockup as a topdressing to their total mixed ration. The supplement consisted of 0, 56, or 112 g of SCFP mixed with 84 g of molasses and 168, 112, or 56 g of corn meal, respectively. Supplement feeding began 28 d before predicted calving date (no less than 14 d) and ended 28 d postpartum, and supplement intake was evaluated daily. Blood samples were collected at d -21, -14, -7, -3, -1, 0, 1, 3, 7, 14, 21, and 28 to measure serum concentrations of macrominerals, metabolites, acute-phase proteins, immunoglobulin, and hormones. Milk weights were measured and milk samples were collected 2 times/wk on nonconsecutive days and analyzed for milk fat, protein, lactose, and somatic cell count (SCC). During the first day after calving, feeding SCFP versus no SCFP decreased serum cortisol concentrations and at least tended to increase supplement intake and serum concentrations of calcium, glucose, urea N, and serum amyloid A. During the first 4 wk postpartum, feeding SCFP versus no SCFP decreased milk SCC and increased milk production and serum phosphorus concentrations. Feeding 112 versus 56 g of SCFP/d did not show additional effects. Feeding SCFP may have a dosage-independent beneficial effect in supporting the physiologic adaptations after parturition, resulting in higher milk production and lower milk SCC.

Growth and Development Symposium: Impacts of inflammation on cattle growth and carcass merit

Inflammation caused by bovine respiratory disease (BRD) continues to be one of the greatest challenges facing beef cattle producers and feedlot managers. Inflammation decreases DMI, ADG, and G:F in feedlot calves, decreasing growth rate and increasing days on feed, which results in economic losses during the feeding period. During the past decade, marketing of feedlot animals has changed from selling cattle on a live basis to a grid-based marketing system. When cattle are marketed on a live basis, the economic effects of BRD stop at increased health cost and decreased feedlot performance, carcass weight, and death loss. However, when cattle are marketed in a grid-based system, inflammation has the potential to also affect carcass cutability and quality. The effects of inflammation on feedlot cattle in regards to performance are well understood; however, specific effects on cattle growth and ultimately carcass merit are not as well described. Recent studies in feedlot cattle have indicated that the incidence of BRD decreases both HCW and marbling; however, mechanisms are not understood. Research in other species has demonstrated that during the acute phase response, pro-inflammatory cytokines promote skeletal muscle catabolism to supply AA and energy substrates for immune tissues. Further, during this early immune response, the liver changes its metabolic priorities to the production of acute phase proteins for use in host defense. Together these dramatic shifts in systemic metabolism may explain the detrimental effects on performance and carcass traits commonly associated with BRD in feedlot calves. Moreover, recent studies relative to human health have revealed complex multilevel interactions between the metabolic and immune systems, and highlighted inflammation as being a significant contributor to major metabolic diseases. The objective of this paper is to review data to help explain the economical and physiological effects of inflammation on cattle growth and carcass merit.

Global endometrial transcriptomic profiling: transient immune activation precedes tissue proliferation and repair in healthy beef cows

BACKGROUND

All cows experience bacterial contamination and tissue injury in the uterus postpartum, instigating a local inflammatory immune response. However mechanisms that control inflammation and achieve a physiologically functioning endometrium, while avoiding disease in the postpartum cow are not succinctly defined. This study aimed to identify novel candidate genes indicative of inflammation resolution during involution in healthy beef cows. Previous histological analysis of the endometrium revealed elevated inflammation 15 days postpartum (DPP) which was significantly decreased by 30 DPP. The current study generated a genome-wide transcriptomic profile of endometrial biopsies from these cows at both time points using mRNA-Seq. The pathway analysis tool GoSeq identified KEGG pathways enriched by significantly differentially expressed genes at both time points. Novel candidate genes associated with inflammatory resolution were subsequently validated in additional postpartum animals using quantitative real-time PCR (qRT-PCR).

RESULTS

mRNA-Seq revealed 1,107 significantly differentially expressed genes, 73 of which were increased 15 DPP and 1,034 were increased 30 DPP. Early postpartum, enriched immune pathways (adjusted P < 0.1) included the T cell receptor signalling pathway, graft-versus-host disease and cytokine-cytokine receptor interaction pathways. However 30 DPP, where the majority of genes were differentially expressed, the enrichment (adjusted P < 0.1) of tissue repair and proliferative activity pathways was observed. Nineteen candidate genes selected from mRNA-Seq results, were independently assessed by qRT-PCR in additional postpartum cows (5 animals) at both time points. SAA1/2, GATA2, IGF1, SHC2, and SERPINA14 genes were significantly elevated 30 DPP and are functionally associated with tissue repair and the restoration of uterine homeostasis postpartum.

CONCLUSIONS

The results of this study reveal an early activation of the immune response which undergoes a temporal functional change toward tissue proliferation and regeneration during endometrial involution in healthy postpartum cows. These molecular changes mirror the activation and resolution of endometrial inflammation during involution previously classified by the degree of neutrophil infiltration. SAA1/2, GATA2, IGF1, SHC2, and SERPINA14 genes may become potential markers for resolution of endometrial inflammation in the postpartum cow.