Project description:This study describes differential miRNA expression in intact colon tissue during acute SIV infection of rhesus macaques. Nine miRNAs were found to be significantly affected by infection, with 5 down-regulated and 4 up-regulated miRNAs. The expression of one upregulated miRNA was further characterized and found to be significantly elevated specifically in response to SIV replication and not immune activation/inflammation accompanying SIV infection. We performed TaqMan Low Density Array based high throughput miRNA analysis on intact colon tissue from 10 acutely SIV-infected and 5 uninfected control macaques. All SIV-infected animals were inoculated intravenously with 100TCID50 of SIV. Out of the ten, one animal each was at 7, 8 and 10DPI (days post infection), 3 each at 13 and 21DPI, and 1 at 29DPI. microRNA reverse transcription and preamplification was performed according to the manufacturerM-bM-^@M-^Ys recommendation. Data analysis was performed using RQ Manager 1.2.2 and DataAssist v3.01 software. Data was normalized using Global normalization method and multiple comparisons correction was performed using Benjamini-Hochberg method.
Project description:The study describes miRNA expression in colonic epithelium of chronic SIV-infected rhesus macaques. We profiled and characterized miRNA/mRNA expression exclusively in colonic epithelium (CE) of 12 chronically SIV-infected and 8 control rhesus macaques (RMs). About 46 miRNAs were differentially expressed (DE) (20-up and 26-down) in CE during chronic SIV infection. Using TargetScan, we bioinformatically crossed the predicted targets of DE miRNAs to genome-wide transcriptomic data and identified several critical miRNA-mRNA pairings that suggested miRNA-mediated regulation of aberrant epithelial gene expression in CE. Immunofluorescence, luciferase reporter and miRNA overexpression studies confirmed the ability of miR-130a and miR-212 to bind the 3’ UTR and downregulate protein expression of occludin (OCLN) and peroxisome proliferator activator receptor gamma (PPAR), respectively, two proteins with pivotal roles in epithelial barrier function. MiR-130a and miR-212 overexpression in Caco-2 cells significantly reduced transepithelial electrical resistance (TEER). Interestingly, delta-9-tetrahydrocannabinol (9-THC) treatment restored TEER to levels observed with control miRNA mimic. Finally, ex-vivo 9-THC treatment of colon tissue from chronically SIV-infected RMs significantly increased PPAR gene expression. Our findings suggest that dysregulated miR-130a and miR-212 expression in CE during chronic HIV/SIV infection can facilitate epithelial barrier disruption by downregulating OCLN and PPAR protein expression. Most importantly, our results highlight the beneficial effects of cannabinoids on epithelial barrier function in not just HIV/SIV but potentially other chronic intestinal inflammatory diseases.
Project description:The study describes miRNA expression in intact duodenum following chronic delta 9 tetrahydrocannabinol (Δ9-THC) administration to SIV-infected rhesus macaques. Chronic Δ9-THC administration to uninfected macaques significantly and positively modulated intestinal miRNA expression by increasing the total number of differentially expressed miRNAs from 14 to 60 days post infection (DPI). At 60DPI, ~28% of miRNAs showed decreased expression in VEH/SIV compared to none in the THC/SIV group. Furthermore, compared to the VEH/SIV group, THC selectively upregulated the expression of miR-10a, miR-24, miR-99b, miR-145, miR-149 and miR-187 previously shown to target proinflammatory molecules. NOX4, a potent reactive oxygen species generator was confirmed as a direct miR-99b target. A significant increase in NOX4+ crypt epithelial cells was detected in VEH/SIV compared to the THC/SIV group. We speculate that miR-99b-mediated NOX4 downregulation may protect the intestinal epithelium from oxidative stress-induced damage.
Project description:This study describes differential miRNA expression in intact colon tissue during acute SIV infection of rhesus macaques. Nine miRNAs were found to be significantly affected by infection, with 5 down-regulated and 4 up-regulated miRNAs. The expression of one upregulated miRNA was further characterized and found to be significantly elevated specifically in response to SIV replication and not immune activation/inflammation accompanying SIV infection.
Project description:The study describes miRNA expression in intact duodenum following chronic delta 9 tetrahydrocannabinol (M-NM-^T9-THC) administration to SIV-infected rhesus macaques. Chronic M-NM-^T9-THC administration to uninfected macaques significantly and positively modulated intestinal miRNA expression by increasing the total number of differentially expressed miRNAs from 14 to 60 days post infection (DPI). At 60DPI, ~28% of miRNAs showed decreased expression in VEH/SIV compared to none in the THC/SIV group. Furthermore, compared to the VEH/SIV group, THC selectively upregulated the expression of miR-10a, miR-24, miR-99b, miR-145, miR-149 and miR-187 previously shown to target proinflammatory molecules. NOX4, a potent reactive oxygen species generator was confirmed as a direct miR-99b target. A significant increase in NOX4+ crypt epithelial cells was detected in VEH/SIV compared to the THC/SIV group. We speculate that miR-99b-mediated NOX4 downregulation may protect the intestinal epithelium from oxidative stress-induced damage. Twelve age and weight matched male Indian rhesus macaques were randomly divided into 4 groups. Group 1 (n=1) received vehicle (1:1:18 of emulphor : alcohol : saline) and no infection. Group 2 (THC only, n=3) animals received twice daily intramuscular injections of M-NM-^T9-THC and no infection. Group-3 THC/SIV, (n=4) animals received twice daily injections of vehicle and were infected intravenously with 100TCID50 of SIVmac251. Group-4 (VEH/SIV, n=4) animals received twice daily injections of M-NM-^T9-THC similar to group 1 for four weeks prior to SIV infection. Duodenal pinch biopsies were collected before infection and thereafter at 14 and 30 days post infection. All animals were necropsied at 60 days post SIV infection. ~100 ng of total RNA was first reverse transcribed and preamplified according to the manufacturerM-bM-^@M-^Ys recommendation. microRNA expression profiling was performed using TaqMan M-BM-.OpenArrayM-BM-. Human microRNA panels. Data analysis was performed using ExpressionSuiteM-BM-. software. Data was normalized to three endogenous controls (RNU44, RNU48 and snoU6). Delta CT values were calculated by subtracting individual miRNA CT values from an average of all three endogenous controls. Comparisons were made between preinfection and all three treatment groups at 14, 30 and 60 DPI. To determine the effect of chronic THC treatment during SIV infection, comparisons were also made between VEH/SIV and THC/SIV at all three time points.
Project description:Hyperimmune activation is one of the strong predictors of disease progression during pathogenic immunodeficiency virus infections and is mediated in part by sustained type I interferon (IFN) signaling. Combination antiretroviral therapy suppresses hyperimmune activation only partially in HIV-infected individuals. Here, we show that blockade of Programmed Death-1 (PD-1) during chonic SIV infection significantly reduces the expression of transcripts associated with type I IFN signaling in the blood and colorectal tissue of rhesus macaques (RM). The effect of PD-1 blockade on type I IFN signaling was durable and persisted under high viremia, a condition that is seen in nonprogressive SIV infection in their natural hosts. The reduced type I IFN signaling was associated with enhanced expression of some of the junction-associated genes in the colorectal tissue and a profound decrease in LPS levels in plasma suggesting a possible repair of gut associated junctions and decreased microbial translocation. The reduced type I IFN signaling was also associated with enhanced immunity against gut resident pathogenic bacteria, control of gut associated opportunistic infections and survival of SIV-infected RMs. These results reveal novel mechanisms by which PD-1 blockade enhances survival of SIV-infected RMs and have implications for development of novel therapeutic approaches to control HIV/AIDS. SIV negative controls (n=4); SIV infected and control antibody (SYNAGIS) treated (n=3); and SIV infected Programmed Death 1 antibody (PD-1 Ab) treated (n=3) groups of Rhesus macaques PBMCs were isolated by Ficoll-paque plus medium (Amersham) and were lysed in to RNA later reagent (Qiagen) and samples were homogenized with Qiagen Shredder (Qiagen). RNA was extracted with Rneasy mini kit (Qiagen) and was used for microarray experiments. Rhesus GeneChip assays were performed in the Yerkes Microarray Core Facility (www.microarray.emory.edu), one of the Affymetrix Microarray Core Labs.The 0.5µg of total RNA sample was analyzed on Rhesus Macaque Genome GeneChip that consists of over 52,000 probe sets (Affymetrix, Santa Clara, CA). Target RNA labeling, hybridization and post-hybridization processing were performed following the Affymetrix GeneChip Expression Analysis standard protocols. In brief, RNA sample was first reverse-transcribed using T7-Oligo(dT) Promoter Primer and SuperScript II in the first-strand cDNAs synthesis reaction. Following RNase H-mediated second-stranded cDNA synthesis, the double-stranded cDNAs were purified by use of a GeneChip sample clean-up module and served as templates in the generation of biotinylated complementary RNAs (cRNAs) in the presence of T7 RNA Polymerase and a biotinylated nucleotide analog/ribonucleotide mix by in vitro transcription (IVT) reaction. The biotinylated cRNAs were cleaned up, fragmented, and hybridized to the rhesus macaque expression arrays at 45°C for 16 h with constant rotation at 60 rpm. The gene chips were then washed and stained with Affymetrix fluidics stations 450 and scanned on Affymetrix scanner 3000. The images are processed to collect raw data with GeneChip Operating Software (GCOS) 1.4.