JAK3 and PI3K mediate bovine Interferon-tau stimulated gene expression in the blood neutrophils

Interferon-tau protects bovine endometrial epithelial cells against inflammatory injury by regulating the PI3K/AKT/β-catenin/FoxO1 signaling axis

Endometritis is one of the most common causes of infertility in dairy cows, and is histopathologically characterized by inflammation and damage of endometrial epithelium. Interferon-tau (IFN-τ) is a novel type I interferon secreted by ruminant trophoblast cells with low cytotoxicity even at high doses. Previous studies suggested that IFN-τ plays an important role in inflammation. However, the mechanisms whereby IFN-τ may modulate the inflammatory responses in the bovine endometrium are unknown. In the present study, primary bovine endometrial epithelial cells (BEEC) isolated from fresh and healthy uterine horns were used for in vitro studies. The integrity of BEEC was assessed by immunofluorescence staining for cytokeratin 18 (CK-18, a known epithelial marker). For the experiments, BEEC were stimulated with different concentrations of lipopolysaccharide (LPS; 0-20 µg/mL) for different times (0-24 h). Cell viability and apoptosis were assessed via CCK-8 and flow cytometry. In a preliminary study, we observed that compared with the control group without LPS, 10 µg/mL of LPS stimulation for 24 h induced apoptosis. In a subsequent study, 20 or 40 ng/mL of IFN-τ alleviated LPS-induced apoptosis. Relative to the LPS group, western blotting further revealed that IFN-τ inhibited the protein abundance of TLR4 and phosphorylated (p-) p65 (p-p65) and Bax/Bcl-2 ratio, suggesting that IFN-τ can protect BEEC against inflammatory injury. Furthermore, the protein abundance of p-phosphoinositide 3-kinase (p-PI3K), p-protein kinase B (p-AKT), p-glycogen synthase kinase-3β (p-GSK3β), β-catenin, and p-forkhead box O1 (p-FoxO1) was lower in the LPS group, whereas IFN-τ upregulated their abundance. The use of LY294002, a specific inhibitor of PI3K/AKT, attenuated the upregulation of p-PI3K, p-AKT p-GSK3β, β-catenin, and p-FoxO1 induced by IFN-τ, and also blocked the downregulation of TLR4, p-p65, and Bax/Bcl-2 ratio. This suggested that the inhibition of TLR4 signaling by IFN-τ was mediated by the PI3K/AKT pathway. Furthermore, compared with the LPS group, the β-catenin agonist SB216763 led to greater p-FoxO1 and lower p-p65 and cell apoptosis. In contrast, knockdown of β-catenin using small interfering RNA had the opposite effects. To explore the role of FoxO1 on the inhibition of TLR4 by IFN-τ, we employed LY294002 to inhibit the PI3K/AKT while FoxO1 was knocked down. Results revealed that the knockdown of FoxO1 blocked the upregulation of TLR4 and p-p65 induced by LY294002, and enhanced the inhibition of IFN-τ on TLR4, p-p65, and cell apoptosis. Overall, these findings confirmed that IFN-τ can protect endometrial epithelial cells against inflammatory injury via suppressing TLR4 activation through the regulation of the PI3K/AKT/β-catenin/FoxO1 axis. These represent new insights into the molecular mechanisms underlying the anti-inflammatory function of IFN-τ in BEEC, and also provide a theoretical basis for further studies on the in vivo application of IFN-τ to help prevent negative effects of endometritis.

Repeated injection of multivitamins and multiminerals during the transition period enhances immune response by suppressing inflammation and oxidative stress in cows and their calves

Periparturient dairy cows undergo major physiological and metabolic changes as well as immunosuppression, associated with decrease in plasma concentrations of various minerals and vitamins. The present study was conducted to investigate effects of repeated injections of vitamins and minerals on oxidative stress, innate and adaptive immune response in periparturient dairy cows and their offspring. Experiment was carried out on 24 peripartum Karan-Fries cows, randomly divided into four groups (n=6): control, Multi-mineral (MM), Multi-vitamin (MV) and Multi-minerals and Multi-vitamin (MMMV). Five ml of MM (Zinc 40 mg/ml, Manganese 10 mg/ml, Copper 15 mg/ml, Selenium 5 mg/ml) and five ml of MV (Vitamin E 5 mg/ml, Vitamin A 1000 IU/ml, B-Complex 5 mg/ml, and Vitamin D₃ 500 IU/ml) were injected intramuscularly (IM) to the MM and MV groups. MMMV group cows were injected with both. In all treatment groups, injections and blood sampling were carried out on 30^th, 15^th, 7^th days before and after expected date of parturition and at calving. In calves, blood was collected at calving and on 1, 2, 3, 4, 7, 8, 15, 30 and 45 days post-calving. Colostrum/milk were collected at calving and at days 2, 4, and 8 post-calving. A lower percentage of total neutrophils and immature neutrophils, higher percentage of lymphocytes together with increased phagocytic activity of neutrophils and proliferative capacity of lymphocytes found in blood of MMMV cows/calves. Lower relative mRNA expression of TLRs and CXCRs and higher mRNA expression of GR-α, CD62L, CD11b, CD25 and CD44 found in blood neutrophils of MMMV groups. Total antioxidant capacity was higher, activity of antioxidant enzymes (SOD and CAT), TBARS levels were lower in the blood plasma of treated cows/calves. In both cows/calves, plasma pro-inflammatory cytokines (IL-1α, IL-1β, IL-6, IL-8, IL-17A, IFN-γ and TNF-α) increased, whereas anti-inflammatory cytokines (IL-4 and IL-10) decreased in MMMV groups. Total immunoglobulins increased in colostrum/milk of MMMV injected cows and plasma of their calves. Results indicate that repeated injections of multivitamins and multiminerals to peripartum dairy cows could be a major strategy to improve immune response and decrease in inflammation and oxidative stress in transition dairy cows and their calves.

Comparative Analysis on Abnormal Methylome of Differentially Expressed Genes and Disease Pathways in the Immune Cells of RA and SLE

We identified abnormally methylated, differentially expressed genes (DEGs) and pathogenic mechanisms in different immune cells of RA and SLE by comprehensive bioinformatics analysis. Six microarray data sets of each immune cell (CD19⁺ B cells, CD4⁺ T cells and CD14⁺ monocytes) were integrated to screen DEGs and differentially methylated genes by using R package “limma.” Gene ontology annotations and KEGG analysis of aberrant methylome of DEGs were done using DAVID online database. Protein-protein interaction (PPI) network was generated to detect the hub genes and their methylation levels were compared using DiseaseMeth 2.0 database. Aberrantly methylated DEGs in CD19⁺ B cells (173 and 180), CD4⁺ T cells (184 and 417) and CD14⁺ monocytes (193 and 392) of RA and SLE patients were identified. We detected 30 hub genes in different immune cells of RA and SLE and confirmed their expression using FACS sorted immune cells by qPCR. Among them, 12 genes (BPTF, PHC2, JUN, KRAS, PTEN, FGFR2, ALB, SERB-1, SKP2, TUBA1A, IMP3, and SMAD4) of RA and 12 genes (OAS1, RSAD2, OASL, IFIT3, OAS2, IFIH1, CENPE, TOP2A, PBK, KIF11, IFIT1, and ISG15) of SLE are proposed as potential biomarker genes based on receiver operating curve analysis. Our study suggests that MAPK signaling pathway could potentially differentiate the mechanisms affecting T- and B- cells in RA, whereas PI3K pathway may be used for exploring common disease pathways between RA and SLE. Compared to individual data analyses, more dependable and precise filtering of results can be achieved by integrating several relevant data sets.

JAK3 and PI3K mediates the suppressive effects of interferon tau on neutrophil extracellular traps formation during peri-implantation period

Interferon tau (IFNτ) is the main maternal signal for pregnancy in ruminants and modulates the functions of various immune cells, including neutrophils. Neutrophil extracellular traps (NETs) are one of the main defence mechanisms of neutrophils. In this study, we observed higher (p < 0.01) ex-vivo NETs extrusion by blood neutrophils from day 16-18 post artificial insemination (AI) in non-inseminated and inseminated non-pregnant cows compared to pregnant cows. In vitro study also showed that IFNτ hampers NETs formation in dose and time dependent manner. The lowest (p < 0.01) NETs formation and the highest (p < 0.01) mRNA expression (RT-PCR) of IFNτ stimulated genes (ISG15, OAS1, MX1) were observed when neutrophil incubated with 9 ng/mL IFNτ for 3.5 h. Signalling cascades mediating IFNτ impairment of NETs formation were identified using inhibitors of JAK2, JAK3, p38, PI3K/Akt and MAPK/Erk. IFNτ reduced (p < 0.01) the mRNA expression (RT-PCR) and concentration (ELISA) of genes and proteins that mediate NETs formation in blood neutrophils including histones (H1, H2), neutrophil elastase (NE) and myeloperoxidase (MPO). However, the effects of IFNτ on these genes and proteins were eliminated in the presence of JAK3 or PI3K inhibitors. Immunocytochemistry study also showed strong MPO signal in the presence of JAK3 or PI3K inhibitors as compared to positive control (PC, IFNτ alone). The results indicate that IFNτ impairs NETs formation using JAK3 and PI3K and thus essential for successful implantation and establishment of pregnancy in cows.

A comparative study on various immunological parameters influencing embryo survivability in crossbred dairy cows

Since long embryonic mortality has remained an area of concern affecting the reproduction, production, and profitability of dairy cows. We investigated the possible interaction between interleukins, hormones, and neutrophil associated CD markers during the implantation window in Karan Fries (KF) cows naturally coming to heat. Blood collection was done on days 0 i.e. day of Artificial Insemination (AI), 10, 18, 21, 30 and on day 40 post-AI. Total leucocyte count (TLC) and neutrophil to lymphocyte (N:L) ratio were recorded. Blood neutrophils were isolated and their number, phagocytic activity (PA), myeloperoxidase (MPO) concentration and relative mRNA expression of cell adhesion molecules (CD-11b, CD-31, CD-44, CD-62L) as well as progesterone-inducing-blocking-factor (PIBF) and glucocorticoid receptor alpha (GRα) were examined. Plasma progesterone, cortisol, IL-2, IL-8, IL-6, and IL-10 were also measured. Pregnancy was confirmed by non-return to heat, ultrasonography and per rectal examination along with progesterone assay. Cows were further divided into pregnant (P), early embryonic mortality (EEM) and late embryonic mortality (LEM) groups. Embryonic losses cows showed lower plasma concentration of IL-10 (<100 pg/ml) and a higher concentration of IL-2 (>500 pg/ml). Also, a 4 fold increase in the relative mRNA expression of CD-11b and 2.5 fold changes in CD-44 expression were observed in embryonic mortality. We observed a 1.5 fold increase in the relative mRNA expression of PIBF and a 0.5 fold increase in GRα expression in pregnant cows compared to EEM (on day 21) and LEM (on days 30 and 40) cows. Our results depicted that the hyperimmune status of the dam which could be due to multifactorial events that led to the pregnancy failure. The above basic values may be used for checking the immune status and thus timely management strategies can be taken to prevent embryonic losses.

Proteomics and transcriptomics study reveals the utility of ISGs as novel molecules for early pregnancy diagnosis in dairy cows

An early and precise diagnosis of pregnancy in cows is critical to short the calving interval and to improve their reproductive efficiency. Neutrophils are the first blood cells to sensitize the embryo in the uterus and participate in maternal recognition of pregnancy after getting induced by interferon tau (IFNτ). To study the protein abundance ratio, blood samples were collected on 0th, 10th, 18th and 36th day post-artificial insemination (AI) from crossbred Karan Fries cows. Neutrophils were isolated through density gradient centrifugation and studied for protein abundance by high-performance liquid chromatography coupled with mass spectrometry (LC-MS). Protein abundance ratios for Myxovirus resistance (MX1 and MX2) were found to be higher (P < 0.05) on day 10 and day 18 post-AI, whereas Oligoadenylate synthetase-1 (OAS1) and Interferon stimulated gene-15 ubiquitin-like modifier (ISG15) proteins were more abundant on day 18 post-AI. The relative mRNA expressions of these molecules were also studied by qPCR. The gene expression of ISG15, MX1, MX2 and OAS1 was found to be higher (P < 0.05) on day 10th, 18th and 36th post-AI compared to day 0. The study indicates that ISGs on blood neutrophils are essential for the establishment of pregnancy and may be targeted as potential biomarkers for pregnancy diagnosis in cows.

Abnormal DNA methylation patterns in patients with infection‑caused leukocytopenia based on methylation microarrays

The present study aimed to investigate the association between gene methylation and leukocytopenia from the perspective of gene regulation. A total of 30 patients confirmed as having post-infection leukocytopenia at People's Hospital of Xinjiang Uygur Autonomous Region between January 2016 and June 2017 were successively recruited as the leukocytopenia group; 30 patients with post-infection leukocytosis were enrolled as the leukocytosis group. In addition, 30 healthy volunteers who received a health examination at the hospital during the same period were included as the normal control group. In each group, four individuals were randomly selected for whole genome methylation screening. After selection of key methylation sites, the remaining samples in each group were used for verification using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. The levels of serum complement factors C3 and C5 in the leukocytopenia group were significantly lower than those in the other two groups (P<0.05). According to whole-genome DNA methylation detection, 66 and 27 methylation loci may be associated with leukocytopenia and leukocytosis, respectively. Most of these abnormal loci are located on chromosomes 2, 6, 7, 1, 17 and 11. The rates of WW domain containing E3 ubiquitin protein ligase 2 gene methylation at cytosine-phosphate-guanine (CpG)_1, CpG_5/6 and CpG_7 in the leukocytopenia group were higher than in the other two groups (P<0.05); the rate of AKT2 CpG_1 methylation was higher in the leukocytopenia group than in the other two groups (P<0.05); the rate of calcium-binding atopy-related autoantigen 1 gene CpG_2 methylation was higher in the leukocytosis group than in the normal control group (P<0.05); and the rate of NADPH oxidase 5 gene CpG_3 methylation was higher in the leukocytosis group than in the normal control group (P<0.05). Chemotactic factor secretion and cell migration abnormalities, ubiquitination modification disorders and reduced oxidative burst may participate in infection-complicated leukocytopenia. The results of this study shed new light on the molecular biological mechanisms of infection-complicated leukocytopenia and provide novel avenues for diagnosis and treatment.