Function and gene expression of circulating neutrophils in dairy cows : impact of micronutrient supplementation

Title from PDF of title page (University of Missouri--Columbia, viewed on October 30, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisor: Dr. Matthew R. WaldronIncludes bibliographical references.Vita.Ph. D. University of Missouri--Columbia 2012."July, 2012"Three experiments were conducted to investigate the mechanisms of neutrophil dysfunction during the periparturient period and test potential nutritional strategies to prevent the immune-alteration typical of this time. The in vitro effects of Escherichia coli lipopolysaccharide (LPS) on the function of bovine neutrophils (PMNL) and expression of selected genes were examined. Lipopolysaccharide directly stimulated PMNL from midlactation cows (n = 7) to produce reactive oxygen species (ROS), and release of neutrophil extracellular traps (NETs) Furthermore, LPS stimulated the gene expression of tumor necrosis factor-α (TNF), bactericidal/permeability increasing protein (BPI) and cytochrome b (CYBA) in PMNL from midlactation (n = 10), but not from early lactation (n = 10) cows. In the second experiment, the effects of a B-vitamin dietary and yeast supplement on the function and global gene expression of PMNL from periparturient dairy cows were tested. Cows received 56 g/day of either OmniGen-AF® (n = 8) or sham control (n = 12) from day 46 before calving until day 31 after parturition. Although no differences in PMNL function were detected between supplemented and non-supplemented cows, Omnigen-AF® down-regulated the expression of genes that enriched the lysosome pathway (upon activation with LPS) and decreased the expression of transcripts in the oxidative phosphorylation pathway (regardless of LPS activation). The objective of the third study was to investigate the effects of trace mineral supplementation from inorganic or organic sources on PMNL function and global gene expression in dairy cows. Thirty nine pregnant Holstein cows were assigned to a basal diet with no added dietary Mn, Co, Cu or Zn (basal, n = 13) or supplemented with 200 mg Mn, 25 mg Co, 125 mg Cu, and 360 mg Zn from inorganic (n = 11) or organic (n = 11) sources. Cows supplemented with trace minerals from inorganic sources had a 39% increase in the amount of E. coli particles phagocytized by PMNL on day 6 postpartum, compared with cows receiving no supplemental trace minerals. Trace mineral supplementation from either inorganic or organic sources resulted in minimal changes in gene expression in non-activated and LPS-activated PMNL, relative to cows fed the basal diet. However, organic trace mineral supplementation (vs. inorganic) up-regulated the expression of genes that enriched the RIG-I-like receptor signaling, cytosolic DNA-sensing, and TOLL-like receptor (TLR) signaling pathways. In conclusion, we identified several cellular and molecular mechanisms of bovine PMNL dysfunction during the periparturient period. In addition, several pathways by which supplementation with micronutrients may impact PMNL performance were discovered.Includes bibliographical reference

Efecto de la aplicación de Hierro Dextrán a terneros recién nacidos Holstein, Jersey y sus cruces sobre su crecimiento en las primeras siete semanas de vida

26 P.La leche no contiene suficiente hierro para satisfacer las necesidades de los terneros cuya capacidad de crecimiento es elevada como consecuencia del mejoramiento genético. Se han usado compuestos de hierro para tratar su deficiencia. Entre junio y diciembre de 2004 se realizó un estudio en Zamorano con el objetivo de determinar el efecto de la aplicación de hierro dextrán (HD; Hierrox®) a terneros recién nacidos sobre su porcentaje de hematocrito, ganancia de peso y aumento de estatura en los primeros 42 días de vida. Se utilizaron 79 terneros machos y hembras de las razas Holstein, Jersey y sus cruces. Se aplicaron 1000 mg de HD vía intramuscular a 39 terneros en las primeras 24 horas de nacidos y 40 terneros se usaron como control. Se usó un diseño completamente al azar (DCA) con medidas repetidas en el tiempo

Functional phenotyping of hepatic lymphocytes in murine MASH by mass cytometry

Summary: Hepatic inflammation, driven by immune cells such as B and T lymphocytes, is a hallmark feature of metabolic dysfunction-associated steatohepatitis (MASH). Here, we detail a robust cytometry by time-of-flight (CyTOF) procedure to phenotype hepatic lymphocytes from mice with MASH. We employ custom metal conjugation of antibodies, isolation of hepatic lymphocytes, cell surface and intracellular staining, and data acquisition. This protocol overcomes the limitations of traditional flow cytometry by accommodating up to 40 markers for comprehensive immune phenotyping.For complete details on the use and execution of this protocol, please refer to Barrow et al.1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics

Non-alcoholic fatty liver disease-related hepatocellular carcinoma: Is there a role for immunotherapy?

Hepatocellular carcinoma (HCC) is among the most common cancers and it is a major cause of cancer-related deaths. Non-alcoholic fatty liver disease (NAFLD) affects approximately one fourth of individuals worldwide and it is becoming one of the most important causes of HCC. The pathogenic mechanisms leading to NAFLD-related HCC are complex and not completely understood. However, metabolic, fibrogenic, oncogenic, inflammatory and immunological pathways seem to be involved. First-line therapy of advanced HCC has recently undergone major changes, since the combination of atezolizumab and bevacizumab was proven to increase survival when compared to sorafenib. Other immune-oncology drugs are also demonstrating promising results in patients with advanced HCC when compared to traditional systemic therapy. However, initial studies raised concerns that the advantages of immunotherapy might depend on the underlying liver disease, which seems to be particularly important in NAFLD-related HCC, as these tumors might not benefit from it. This article will review the mechanisms of NAFLD-related hepatocarcinogenesis, with an emphasis on its immune aspects, the efficacy of traditional systemic therapy for advanced NAFLD-related HCC, and the most recent data on the role of immunotherapy for this specific group of patients, showing that the management of this condition should be individualized and that a general recommendation cannot be made at this time

Nucleic Acid-Targeting Pathways Promote Inflammation in Obesity-Related Insulin Resistance

Obesity-related inflammation of metabolic tissues, including visceral adipose tissue (VAT) and liver, are key factors in the development of insulin resistance (IR), though many of the contributing mechanisms remain unclear. We show that nucleic-acid-targeting pathways downstream of extracellular trap (ET) formation, unmethylated CpG DNA, or ribonucleic acids drive inflammation in IR. High-fat diet (HFD)-fed mice show increased release of ETs in VAT, decreased systemic clearance of ETs, and increased autoantibodies against conserved nuclear antigens. In HFD-fed mice, this excess of nucleic acids and related protein antigens worsens metabolic parameters through a number of mechanisms, including activation of VAT macrophages and expansion of plasmacytoid dendritic cells (pDCs) in the liver. Consistently, HFD-fed mice lacking critical responders of nucleic acid pathways, Toll-like receptors (TLR)7 and TLR9, show reduced metabolic inflammation and improved glucose homeostasis. Treatment of HFD-fed mice with inhibitors of ET formation or a TLR7/9 antagonist improves metabolic disease. These findings reveal a pathogenic role for nucleic acid targeting as a driver of metabolic inflammation in IR