Glomerulonephritis and autoimmune vasculitis are independent of P2RX7 but may depend on alternative inflammasome pathways.

P2RX7, an ionotropic receptor for extracellular adenosine triphosphate (ATP), is expressed on immune cells, including macrophages, monocytes, and dendritic cells and is upregulated on nonimmune cells following injury. P2RX7 plays a role in many biological processes, including production of proinflammatory cytokines such as interleukin (IL)-1ß via the canonical inflammasome pathway. P2RX7 has been shown to be important in inflammation and fibrosis and may also play a role in autoimmunity. We have developed and phenotyped a novel P2RX7 knockout (KO) inbred rat strain and, taking advantage of the human-resembling unique histopathological features of rat models of glomerulonephritis, we induced three models of disease: nephrotoxic nephritis, experimental autoimmune glomerulonephritis, and experimental autoimmune vasculitis. We found that deletion of P2RX7 does not protect rats from models of experimental glomerulonephritis or the development of autoimmunity. Notably, treatment with A-438079, a P2RX7 antagonist, was equally protective in WKY WT and P2RX7 KO rats, revealing its 'off-target' properties. We identified a novel ATP/P2RX7/K+ efflux-independent and caspase-1/8-dependent pathway for the production of IL-1ß in rat dendritic cells, which was absent in macrophages. Taken together, these results comprehensively establish that inflammation and autoimmunity in glomerulonephritis is independent of P2RX7 and reveals the off-target properties of drugs previously known as selective P2RX7 antagonists. Rat mononuclear phagocytes may be able to utilise an 'alternative inflammasome' pathway to produce IL-1ß independently of P2RX7, which may account for the susceptibility of P2RX7 KO rats to inflammation and autoimmunity in glomerulonephritis. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Live Imaging of Monocyte Subsets in Immune Complex-Mediated Glomerulonephritis Reveals Distinct Phenotypes and Effector Functions.

BACKGROUND: Immune complexes within glomerular capillary walls cause crescentic GN (CrGN). Monocytes and macrophages are important in mediating CrGN, but little work has been done to phenotype the subpopulations involved and determine their respective contributions to glomerular inflammation. METHODS: Live glomerular imaging using confocal microscopy monitored intravascular monocyte subset behavior during nephrotoxic nephritis (NTN) in a novel WKY-hCD68-GFP monocyte/macrophage reporter rat strain. Flow cytometry and qPCR further analyzed ex vivo the glomerular leukocyte infiltrate during NTN. RESULTS: Non-classical monocytes surveyed the glomerular endothelium via lymphocyte function-associated antigen 1 (LFA-1) in the steady state. During NTN, non-classical monocytes were recruited first, but subsequent recruitment and retention of classical monocytes was associated with glomerular damage. Monocytes recruited to the glomerular vasculature did not undergo transendothelial migration. This finding suggests that inflammation in immune complex-mediated CrGN is predominantly intravascular, driven by dynamic interactions between intravascular blood monocytes and the endothelium. Glomerular endothelium and non-classical monocytes overexpressed a distinct chemokine axis, which may orchestrate inflammatory myeloid cell recruitment and expression of damage mediators. Reduced classical monocyte recruitment in Lewis rats during NTN confirmed a role for CD16 in mediating glomerular damage. CONCLUSIONS: Monocyte subsets with distinct phenotypes and effector functions may be important in driving inflammation in experimental CrGN resulting from immune complexes formed within the glomerular capillary wall. LFA-1-dependent endothelial surveillance by non-classical monocytes may detect immune complexes through CD16, orchestrating the inflammatory response through intravascular retention of classical monocytes, which results in glomerular damage and proteinuria.

Cardiac rehabilitation and outcome in stable outpatients with recent myocardial infarction.

OBJECTIVE: To compare the mortality rate and the rate of subsequent ischemic events (myocardial infarction [MI], ischemic stroke, or limb amputation) in patients with recent MI according to the use of cardiac rehabilitation or no rehabilitation. DESIGN: Longitudinal observational study. SETTING: Ongoing registry of outpatients. PARTICIPANTS: Patients (N=1043) with recent acute MI were recruited; of these, 521 (50%) participated in cardiac rehabilitation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Subsequent ischemic events and mortality rates were registered. RESULTS: Over a mean follow-up of 18 months, 50 patients (4.8%) died and 49 (4.7%) developed 52 subsequent ischemic events (MI: n=43, ischemic stroke: n=6, limb amputation: n=3). Both the mortality rate (.16 vs 5.57 deaths per 100 patient-years; rate ratio=.03; 95% confidence interval [CI], 0.0-0.1]) and the rate of subsequent ischemic events (1.65 vs 4.54 events per 100 patient-years; rate ratio=0.4; 95% CI, 0.2-0.7) were significantly lower in cardiac rehabilitation participants than in nonparticipants. Multivariate analysis confirmed that patients in cardiac rehabilitation had a significantly lower risk of death (hazard ratio=.08; 95% CI, .01-.63; P=.016) and a nonsignificant lower risk of subsequent ischemic events (hazard ratio=.65; 95% CI, .30-1.42). CONCLUSIONS: The use of cardiac rehabilitation in patients with recent MI was independently associated with a significant decrease in the mortality rate and a nonsignificant decrease in the rate of subsequent ischemic events.

Alcohol consumption and outcome in stable outpatients with peripheral artery disease.

BACKGROUND: The influence of alcohol consumption on outcome in patients with peripheral artery disease (PAD) has not been thoroughly studied. METHODS: Factores de Riesgo y ENfermedad Arterial (FRENA) is an ongoing, multicenter, observational registry of consecutive stable outpatients with arterial disease. We compared the mortality rate and the incidence of subsequent ischemic events in patients with PAD, according to their alcohol habits. RESULTS: As of August 2010, 1073 patients with PAD were recruited, of whom 863 (80%) had intermittent claudication (Fontaine stage II), 102 (9.5%) had rest pain (Fontaine stage III), and 108 (10%) had ischemic skin lesions (Fontaine stage IV). In all, 422 patients (39%) consumed alcohol during the study period. Over a mean follow-up of 13 months, 150 patients (14%) developed subsequent ischemic events (myocardial infarction 28, stroke 30, disabling claudication/critical limb ischemia 100), and 70 patients (6.5%) died. The incidence of subsequent events was the same in both subgroups: 11.8 events per 100 patient-years (rate ratio: 1.00; 95% confidence interval [CI], 0.72-1.41), but the mortality rate was significantly lower in alcohol consumers than in non-consumers: 2.78 vs 6.58 deaths per 100 patient-years (rate ratio: 0.42; 95% CI, 0.23-0.74; P = .002). This better outcome was consistently found in patients with Fontaine stages II and III or IV, and persisted after multivariate adjustment (relative risk: 0.49; 95% CI, 0.28-0.88). CONCLUSIONS: In patients with PAD, moderate alcohol consumption was associated with lower cardiovascular mortality and overall mortality than abstention. These patients should be informed that low to moderate alcohol consumption may not be harmful to their health.

Selective Interleukin-6 Trans-Signaling Blockade Is More Effective Than Panantagonism in Reperfused Myocardial Infarction.

Interleukin (IL)-6 is an emerging therapeutic target in myocardial infarction (MI). IL-6 has 2 distinct signaling pathways: trans-signaling, which mediates inflammation, and classic signaling, which also has anti-inflammatory effects. The novel recombinant fusion protein sgp130Fc achieves exclusive trans-signaling blockade, whereas anti-IL-6 antibodies (Abs) result in panantagonism. In a rat model of reperfused MI, sgp130Fc, but not anti-IL-6-Ab, attenuated neutrophil and macrophage infiltration into the myocardium, reduced infarct size, and preserved cardiac function 28 days after MI. These data demonstrate the efficacy of exclusive IL-6 trans-signaling blockade and support further investigation of sgp130Fc as a potential novel therapy in MI.

Comparative evaluation of the ExaVir Load version 3 reverse transcriptase assay for measurement of human immunodeficiency virus type 1 plasma load.

In resource-limited settings, the virological monitoring of antiretroviral therapy is limited by high cost and the lack of infrastructure. The Cavidi ExaVir Load assay employs a simple and inexpensive enzyme-linked immunosorbent assay format to measure human immunodeficiency virus (HIV) reverse transcriptase activity, which correlates with plasma RNA load. The version 3 assay has been described as having improved precision and sensitivity. There are limited data on its performance relative to those of current real-time assays. Our objective was to compare HIV type 1 (HIV-1) RNA load measurement in plasma by ExaVir Load version 3 (designated ExaVir), Abbott M2000sp/M2000rt RealTime HIV-1 assay (designated RealTime), and Roche COBAS Ampliprep/COBAS TaqMan HIV-1 version 1 assay (designated TaqMan). Plasma from 119 patients (34 with subtype B infection, 85 with non-subtype B infection [A-H, CRF01, CRF02, CRF06, CRF12, CRF14, and complex]; 48 subjects were treatment experienced, 71 were naive) and serial dilutions of the second international standard (IS) were tested. Assay relationship and agreement were determined by linear regression, correlation analysis, and the Bland-Altman method. The ExaVir assay quantified 77/83 (92.8%) samples with viral loads of >2.3 log10 copies/ml by the molecular assays. Results were linearly associated and strongly correlated with RealTime and TaqMan measurements (R of 0.94 and 0.92, respectively) for both subtype B (R of 0.97 and 0.95, respectively) and non-subtype B (R of 0.93 and 0.91, respectively) samples. Mean differences were 0.28 and 0.18 log10 copies/ml in favor of the two molecular assays; 7/119 (5.9%) and 5/119 (4.2%) samples were outside the 95% level of agreement. ExaVir underquantified the IS by a mean of 0.2 (range, 0.0 to 0.5) log10 copies/ml. The ExaVir assay showed excellent concordance with real-time molecular assays, offering a suitable option for virological monitoring in settings with limited infrastructure.

Determinants of virological failure after successful viral load suppression in first-line highly active antiretroviral therapy.

BACKGROUND: We aimed to investigate the long-term virological outcomes of a cohort initially showing good responses to first-line highly active antiretroviral therapy (HAART) with no evidence ofvirological failure during the first year after achieving viral load (VL) undetectability (<50 copies/ml). METHODS: Virological failure was defined as a confirmed VL >400 copies/ml or a single VL >400 copies/ml followed by a treatment change or end of follow-up. Risk factors for low-level VL rebound (50-400 copies/ml) in the first year after achieving undetectability and for virological failure during subsequent follow-up were investigated by logistic and Poisson regression. RESULTS: In the first year after achieving VL undetectability, 354/1386 (25.5%) patients experienced low-level VL rebound, the remaining patients maintained consistent undetectability. Low-level rebound occurred less commonly with non-nucleoside reverse transcriptase inhibitor (NNRTI)-based HAART than with other regimens (P = 0.01). Over median 2.2 (range 0.0-7.4) years of subsequent follow-up, 86 (6.2%) patients experienced virological failure, corresponding to 2.30 failures per 100 person-years (95% confidence interval [CI] 1.82-2.79). Independent predictors of virological failure included low-level rebound during the first year after achieving undetectability relative to consistent undetectability (rate ratio [RR] 2.18, 95%0 CI 1.15-4.10), female gender (RR 1.79, 95% CI 1.12-2.85) and receiving a ritonavir-boosted protease inhibitor (Pl/r) relative to NNRTI-based HAART (RR 1.88, 95% CI 1.02-3.46). CONCLUSIONS: Patients on first-line HAART who maintain consistent VL undetectability for 1 year have a low risk of subsequent virological failure. A subset might benefit from targeted interventions, including women and patients on Pl/r-based HAART.

Detection of low-frequency K103N mutants after unstructured discontinuation of efavirenz in the presence of the CYP2B6 516 TT polymorphism.

OBJECTIVES: To measure antiretroviral drug plasma levels in newly diagnosed HIV-1 seropositive persons who presented with an undetectable plasma HIV-1 RNA load but gave no history of antiretroviral drug exposure and to determine the impact of interrupting undisclosed or unknown antiretroviral therapy on the emergence of drug resistance. PATIENTS AND METHODS: Five newly diagnosed, reportedly drug-naive HIV-1 seropositive persons were included in the study. Drug resistance was determined by population and clonal sequencing of reverse transcriptase and protease. CYP2B6 polymorphisms were assayed by real-time PCR allelic discrimination on pre-amplified exons. RESULTS: Efavirenz was detected in the plasma of one of the five persons coinciding with a viral load <40 copies/mL by two different assays. When efavirenz became undetectable, the viral load rebounded. The patient was CYP2B6-516T homozygous. Population sequencing showed wild-type subtype D virus, whereas clonal sequencing detected low-frequency (2%) K103N. The patient firmly denied antiretroviral exposure but described the use of Ugandan remedies. CONCLUSIONS: In migrating populations seeking HIV testing, careful and compassionate counselling is required to facilitate the disclosure of previous diagnosis and therapy. The use of remedies of dubious content should also be discussed and investigated.

Raised Fibrinogen Levels and Outcome in Outpatients With Peripheral Artery Disease.

The influence of raised fibrinogen levels on outcome in stable outpatients with peripheral arterial disease (PAD) has not been consistently investigated. We used data from the Factores de Riesgo y ENfermedad Arterial (FRENA) registry to compare ischemic events, major bleeding, and mortality in stable outpatients with PAD, according to their baseline plasma fibrinogen levels. Of 1363 outpatients with PAD recruited in FRENA, 558 (41%) had fibrinogen levels >450 mg/100 mL. Over 18 months, 43 patients presented with acute myocardial infarction, 37 had an ischemic stroke, 51 underwent limb amputation, 19 had major bleeding, and 90 died. Compared to patients with normal levels, those with raised fibrinogen levels had an over 2-fold higher rate of ischemic stroke (rate ratio [RR]: 2.30; 95% confidence interval [CI]: 1.19-4.59), limb amputation (RR: 2.58; 95% CI: 1.46-4.67), or death (RR: 2.27; 95% CI: 1.49-3.51) and an over 3-fold higher rate of major bleeding (RR: 3.90; 95% CI: 1.45-12.1). On multivariate analysis, patients with raised fibrinogen levels had an increased risk of developing subsequent ischemic events (hazard ratio [HR]: 1.61; 95% CI: 1.11-2.32) and major bleeding (HR: 3.42; 95% CI: 1.22-9.61). Stable outpatients with PAD and raised plasma fibrinogen levels had increased rates of subsequent ischemic events and major bleeding.

Genetic, physiological and comparative genomic studies of hypertension and insulin resistance in the spontaneously hypertensive rat.

We previously mapped hypertension-related insulin resistance quantitative trait loci (QTLs) to rat chromosomes 4, 12 and 16 using adipocytes from F2 crosses between spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats, and subsequently identified Cd36 as the gene underlying the chromosome 4 locus. The identity of the chromosome 12 and 16 genes remains unknown. To identify whole-body phenotypes associated with the chromosome 12 and 16 linkage regions, we generated and characterised new congenic strains, with WKY donor segments introgressed onto an SHR genetic background, for the chromosome 12 and 16 linkage regions. We found a >50% increase in insulin sensitivity in both the chromosome 12 and 16 strains. Blood pressure and left ventricular mass were reduced in the two congenic strains consistent with the congenic segments harbouring SHR genes for insulin resistance, hypertension and cardiac hypertrophy. Integrated genomic analysis, using physiological and whole-genome sequence data across 42 rat strains, identified variants within the congenic regions in Upk3bl, RGD1565131 and AABR06087018.1 that were associated with blood pressure, cardiac mass and insulin sensitivity. Quantitative trait transcript analysis across 29 recombinant inbred strains showed correlation between expression of Hspb1, Zkscan5 and Pdgfrl with adipocyte volume, systolic blood pressure and cardiac mass, respectively. Comparative genome analysis showed a marked enrichment of orthologues for human GWAS-associated genes for insulin resistance within the syntenic regions of both the chromosome 12 and 16 congenic intervals. Our study defines whole-body phenotypes associated with the SHR chromosome 12 and 16 insulin-resistance QTLs, identifies candidate genes for these SHR QTLs and finds human orthologues of rat genes in these regions that associate with related human traits. Further study of these genes in the congenic strains will lead to robust identification of the underlying genes and cellular mechanisms.

Complement Factor B Is a Determinant of Both Metabolic and Cardiovascular Features of Metabolic Syndrome.

CFB (complement factor B) is elevated in adipose tissue and serum from patients with type 2 diabetes mellitus and cardiovascular disease, but the causal relationship to disease pathogenesis is unclear. Cfb is also elevated in adipose tissue and serum of the spontaneously hypertensive rat, a well-characterized model of metabolic syndrome. To establish the role of CFB in metabolic syndrome, we knocked out the Cfb gene in the spontaneously hypertensive rat. Cfb-/- rats showed improved glucose tolerance and insulin sensitivity, redistribution of visceral to subcutaneous fat, increased adipocyte mitochondrial respiration, and marked changes in gene expression. Cfb-/- rats also had lower blood pressure, increased ejection fraction and fractional shortening, and reduced left ventricular mass. These changes in metabolism and gene expression, in adipose tissue and left ventricle, suggest new adipose tissue-intrinsic and blood pressure-independent mechanisms for insulin resistance and cardiac hypertrophy in the spontaneously hypertensive rat. In silico analysis of the human CFB locus revealed 2 cis-regulated expression quantitative trait loci for CFB expression significantly associated with visceral fat, circulating triglycerides and hypertension in genome-wide association studies. Together, these data demonstrate a key role for CFB in the development of spontaneously hypertensive rat metabolic syndrome phenotypes and of related traits in humans and indicate the potential for CFB as a novel target for treatment of cardiometabolic disease.

Von Willebrand Factor Gene Variants Associate with Herpes simplex Encephalitis.

Herpes simplex encephalitis (HSE) is a rare complication of Herpes simplex virus type-1 infection. It results in severe parenchymal damage in the brain. Although viral latency in neurons is very common in the population, it remains unclear why certain individuals develop HSE. Here we explore potential host genetic variants predisposing to HSE. In order to investigate this we used a rat HSE model comparing the HSE susceptible SHR (Spontaneously Hypertensive Rats) with the asymptomatic infection of BN (Brown Norway). Notably, both strains have HSV-1 spread to the CNS at four days after infection. A genome wide linkage analysis of 29 infected HXB/BXH RILs (recombinant inbred lines-generated from the prior two strains), displayed variable susceptibility to HSE enabling the definition of a significant QTL (quantitative trait locus) named Hse6 towards the end of chromosome 4 (160.89-174Mb) containing the Vwf (von Willebrand factor) gene. This was the only gene in the QTL with both cis-regulation in the brain and included several non-synonymous SNPs (single nucleotide polymorphism). Intriguingly, in human chromosome 12 several SNPs within the intronic region between exon 43 and 44 of the VWF gene were associated with human HSE pathogenesis. In particular, rs917859 is nominally associated with an odds ratio of 1.5 (95% CI 1.11-2.02; p-value = 0.008) after genotyping in 115 HSE cases and 428 controls. Although there are possibly several genetic and environmental factors involved in development of HSE, our study identifies variants of the VWF gene as candidates for susceptibility in experimental and human HSE.

New Wistar Kyoto and spontaneously hypertensive rat transgenic models with ubiquitous expression of green fluorescent protein.

The Wistar Kyoto (WKY) rat and the spontaneously hypertensive (SHR) rat inbred strains are well-established models for human crescentic glomerulonephritis (CRGN) and metabolic syndrome, respectively. Novel transgenic (Tg) strains add research opportunities and increase scientific value to well-established rat models. We have created two novel Tg strains using Sleeping Beauty transposon germline transgenesis, ubiquitously expressing green fluorescent protein (GFP) under the rat elongation factor 1 alpha (EF1a) promoter on the WKY and SHR genetic backgrounds. The Sleeping Beauty system functioned with high transgenesis efficiency; 75% of new rats born after embryo microinjections were transgene positive. By ligation-mediated PCR, we located the genome integration sites, confirming no exonic disruption and defining a single or low copy number of the transgenes in the new WKY-GFP and SHR-GFP Tg lines. We report GFP-bright expression in embryos, tissues and organs in both lines and show preliminaryin vitroandin vivoimaging data that demonstrate the utility of the new GFP-expressing lines for adoptive transfer, transplantation and fate mapping studies of CRGN, metabolic syndrome and other traits for which these strains have been extensively studied over the past four decades.

Prevalence of baseline polymorphisms for potential resistance to NS5A inhibitors in drug-naive individuals infected with hepatitis C genotypes 1-4.

BACKGROUND: The non-structural 5A (NS5A) protein of HCV is a multifunctional phosphoprotein involved in regulation of viral replication and virion assembly. NS5A inhibitors targeting domain I of NS5A protein have demonstrated high potency and pan-genotypic antiviral activity, however they possess a low genetic barrier to resistance. At present, only genotype 1, the most prevalent HCV genotype has been studied in detail for resistant variants. METHODS: Utilizing a panel of genotypic-specific resistance assays, population sequencing was performed on plasma-derived viral RNA isolated from 138 patients infected with HCV genotypes 1-4 and not treated with direct-acting antiviral agents. Amino acid changes in HCV NS5A domain I at codon positions 28, 30, 31, 32 and 93, reported to confer reduced susceptibility to certain NS5A inhibitors were examined. Additionally, genotypic outcome based on NS5A sequences were compared with VERSANT HCV Genotype Assay (LiPA) 1.0 (Siemens Healthcare Diagnostics, Surrey, UK) and Abbott m2000 RealTime HCV genotype II assay (Abbott Molecular, Maidenhead, Berkshire, UK). RESULTS: Amino acid substitutions associated with moderate to high level resistance to NS5A inhibitors were detected in 2/42 (4.76%) HCV-1a, 3/23 (13.04%) HCV-1b, 4/26 (15.38%) HCV-2, 1/24 (4.17%) HCV-3 and 1/23 (4.35%) HCV-4 infected patients who had not been treated with NS5A inhibitors. Genotype prediction based on NS5A sequences were concordant with LiPA and/or Abbott RealTime for 97.10% of cases. CONCLUSIONS: Primary resistance mutations associated with resistance to first-generation NS5A inhibitors such as daclatasvir were observed in all genotypes, albeit at low frequencies. An excellent correlation based on NS5A genotyping and LiPA or Abbott RealTime was achieved.

Analysis of transmitted HIV-1 drug resistance using 454 ultra-deep-sequencing and the DeepChek(®)-HIV system.

INTRODUCTION: Next-generation sequencing (NGS) is capable of detecting resistance-associated mutations (RAMs) present at frequencies of 1% or below. Several studies have found that baseline low-frequency RAMs are associated with failure to first-line HAART. One major limitation to the expansion of this technology in routine diagnostics is the complexity and laboriousness integral to bioinformatics analysis. DeepChek (ABL, TherapyEdge) is a CE-marked software that allows automated analysis and resistance interpretation of NGS data. OBJECTIVE: To evaluate the use of 454 ultra-deep-sequencing (Roche(®) 454, Life Sciences; 454-UDS) and DeepChek for routine baseline resistance testing in a clinical diagnostic laboratory. METHODS: 107 newly diagnosed HIV-1-infected patients (subtypes: A, n=9; B, n=52; C, n=21; D, n=2; F, n=3; G, n=1; CRF01, n=7; CRF02, n=7; CRF06, n=1; CRF07, n=1; CRF10, n=1 and unassigned complex, n=2) with a median plasma viral load of 88,727 copies/mL (range: 1380-2,143,543) were tested by 454-UDS and Sanger sequencing for the detection of protease and reverse transcriptase RAMs. In addition, integrase RAMs were investigated in 57 of them. Sequence analysis and resistance interpretation were performed using DeepChek applying 1% and 20% thresholds for variant detections; filters applied were comparison between Sanger and 454-UDS, and Stanford and IAS list for resistance interpretation. RESULTS: The time elapsed from generation of raw 454 data (between 2,000-5,000 sequences/sample) to elaboration of a resistance report was approximately 10 minutes per sample, equivalent to the time required for the same process using Sanger sequencing. Four patients (3.7%) showed baseline resistance by Sanger and 454-UDS at frequencies above 20%, which affected both NRTIs (n=2) and NNRTIs (n=2). In addition, 12 patients (11.2%) showed transmitted drug resistance (TDR) by 454-UDS at frequencies below 20% affecting NRTIs (n=9), NNRTIs (n=7) and PIs (n=2). Integrase resistance was not detected at baseline by 454-UDS or Sanger sequencing. CONCLUSIONS: DeepChek allowed easy and rapid analysis and interpretation of NGS data, thus facilitating the incorporation of this technology in routine diagnostics. The use of NGS considerably increased the detection rates of TDR to NRTI, NNRTIs and PIs. No transmitted resistance to integrase inhibitors was found in our population by Sanger sequencing or UDS.

Telaprevir or boceprevir based therapy for chronic hepatitis C infection: development of resistance-associated variants in treatment failure.

The use of triple-therapy, pegylated-interferon, ribavirin and either of the first generation hepatitis C virus (HCV) protease inhibitors telaprevir or boceprevir, is the new standard of care for treating genotype 1 chronic HCV. Clinical trials have shown response rates of around 70-80%, but there is limited data from the use of this combination outside this setting. Through an expanded access programme, we treated 59 patients, treatment naïve and experienced, with triple therapy. Baseline factors predicting treatment response or failure during triple therapy phase were identified in 58 patients. Thirty seven (63.8%) of 58 patients had undetectable HCV RNA 12weeks after the end of treatment. Genotype 1a (p=0.053), null-response to previous treatment (p=0.034), the rate of viral load decline after 12weeks of previous interferon-based treatment (p=0.033) were all associated with triple-therapy failure. The most common cause of on-treatment failure for telaprevir-based regimens was the development of resistance-associated variants (RAVs) at amino acids 36 and/or 155 of HCV protease (p=0.027) whereas in boceprevir-based regimens mutations at amino acid 54 were significant (p=0.015). SVR12 rates approaching 64% were achieved using triple therapy outside the clinical trial setting, in a patient cohort that included cirrhotics.

The utility of different bioinformatics algorithms for genotypic HIV-1 tropism testing in a large clinical cohort with multiple subtypes.

OBJECTIVES: HIV-1 tropism needs to be determined before the use of CCR5 antagonist drugs such as maraviroc (MVC), which are ineffective against CXCR4-using HIV-1. This study assessed how different computational methods for predicting tropism from HIV sequence data performed in a large clinical cohort. The value of adding clinical data to these algorithms was also investigated. DESIGN AND METHODS: PCR amplification and sequence analysis of the HIV-1 gp120 V3 loop region was performed on triple replicates of plasma viral RNA or proviral DNA extracted from peripheral blood monocytes (PBMCs) in 242 patients. Coreceptor usage was predicted from V3 sequences using seven bioinformatics interpretation algorithms, combined with clinical data where appropriate. An intention-to-treat approach was employed for exploring outcomes and performance for different viral subtypes was examined. RESULTS: The frequency of R5 predictions varied by 22.6%, with all seven algorithms agreeing for only 75.3% of tests. The identification of individuals likely to fail was poor for all algorithms. The addition of clinical data improved this, but at the expense of their ability to predict success. The clinical algorithms varied across subtypes, whereas other algorithms were more consistent. Furthermore, individuals with discordant clonal and clinical predictions were more likely to fail MVC treatment. CONCLUSION: Eligibility for MVC varied depending on the algorithm method used. The addition of clinical parameters alongside sequence data may help predict X4 emergence during treatment. It could be that V3 loop analysis in isolation may not be the best method for selecting individuals for MVC.

Comparative evaluation of the Artus HIV-1 QS-RGQ assay and the Abbott RealTime HIV-1 assay for the quantification of HIV-1 RNA in plasma.

BACKGROUND: The quantitative measurement of HIV-1 RNA levels in plasma ('viral load') is essential in the management of HIV-infected patients. OBJECTIVE: The new Artus HIV-1 QS-RGQ assay ('Artus(HIV)') for HIV-1 RNA quantification in plasma was compared to the Abbott RealTime HIV-1 assay ('RealTime') following automated RNA isolation by the QIAsymphony and Abbott m2000 extractors, respectively. Emphasis was placed on assay performance with diverse HIV-1 subtypes and in patients receiving antiretroviral therapy (ART). STUDY DESIGN: Plasma from 211 patients (105 subtype B, 87 non-B subtypes; 147 on ART) and serial dilutions of the WHO 2nd International HIV-1 RNA Standard (WHO-IS) were tested by the two assays in parallel. Assay relationship and agreement were determined by linear regression, correlation analysis, and Bland-Altman analysis. RESULTS: With 125 specimens quantified by both assays, measurements were linearly associated and strongly correlated. Overall Artus reported higher levels by mean 0.24 (95% confidence interval [CI] 0.16-0.32) log(10) copies/ml (P < 0.0001); 5 samples (subtypes A, B, CRF01, CRF03) fell outside the 95% agreement. Discordant results were obtained with 11 and 13 samples quantified by either ArtusHIV or RealTime alone respectively, at levels generally close to the lower limit of quantification, giving an overall discordance rate of 24/211 (11%). Both assays generally under-quantified the WHO-IS by between 0.1 and 0.4 log(10) copies/ml across seven dilutions. CONCLUSIONS: The ArtusHIV assay offers performance comparable to that of the RealTime assay across a wide range of HIV-1 subtypes and among both treated and untreated patients.

Renal function and short-term outcome in stable outpatients with coronary, cerebrovascular or peripheral artery disease.

BACKGROUND: The influence of renal function on outcome in stable outpatients with atherosclerotic disease has not been thoroughly studied. METHODS: We used the FRENA Registry data to compare the incidence of subsequent ischemic events (myocardial infarction [MI], ischemic stroke or limb amputation) in patients with coronary (CAD), cerebrovascular (CVD) or peripheral artery disease (PAD), according to their estimated glomerular filtration rate (eGFR) at baseline. RESULTS: As of April 2012, 3860 patients were recruited in FRENA: 1439 with CAD, 1118 with CVD and 1303 with PAD. Over a mean follow-up of 14 ± 12 months, 97 patients suffered subsequent MI, 93 had ischemic stroke and 46 underwent limb amputation. In all, 2699 patients (70%) had eGFR > 60 mL/min/1.73 m(2), 1022 (26%) had 30-60 mL/min/1.73 m(2), and 139 (3.6%) had <30 mL/min/1.73 m(2). Among patients with CAD, the rate of subsequent MI was: 1.38 (95% CI: 0.85-2.11), 5.79 (95% CI: 3.90-8.31) and 18.8 (95% CI: 9.14-34.4) events per 100 patient-years, respectively. On multivariable analysis, the hazard ratio for MI (compared with patients with eGFR > 60 mL/min/1.73 m(2)) was of 1.77 (95% CI: 1.15-2.73) for patients with eGFR of 30-60 mL/min/1.73 m(2), and 3.15 (95% CI: 1.61-6.14) for those with eGFR < 30 mL/min/1.73 m(2). Among patients with CVD or PAD, there was no increasing rate of subsequent ischemic events with decreasing renal function. CONCLUSIONS: Among stable outpatients with CAD, there is an increasing rate of subsequent MI with decreasing renal function, independently of potentially confounding variables. These findings were not observed in patients with CVD or PAD.

Clinical outcome of stable outpatients with coronary, cerebrovascular or peripheral artery disease, and atrial fibrillation.

BACKGROUND: The influence of atrial fibrillation (AF) on outcome in patients with symptomatic atherosclerotic disease has not been thoroughly studied. METHODS: FRENA is an ongoing registry of stable outpatients with coronary (CAD), cerebrovascular (CVD), or peripheral (PAD) artery disease. With the aim to guide therapy, we assessed the incidence of subsequent myocardial infarction (MI), ischemic stroke or major bleeding in patients with AF, according to initial presentation. RESULTS: As of June 2011, 3848 patients were recruited: 1436 had CAD, 1104 CVD, and 1308 had PAD. Of these, 470 (12%) had AF: 151 patients with CAD, 157 with CVD, and 162 with PAD. Over a mean follow-up of 16 ± 13 months, 19 patients with AF developed acute MI, 22 ischemic stroke and 7 bled. Among AF patients with CAD, the incidence of subsequent MI (5.00 events per 100 patient-years; 95% CI: 2.54-8.91) was non-significantly higher than that of stroke (1.48; 95% CI: 0.38-4.04) or major bleeding (1.47; 95% CI: 0.37-4.01). Among those with CVD, the incidence of stroke (5.61; 95% CI: 2.95-9.75) exceeded that of MI (no events) or major bleeding (0.51; 95% CI: 1.24-6.36). Among those with PAD, the incidence of MI (4.41; 95% CI: 2.15-8.10) and stroke (3.93; 95% CI: 1.82-7.46) were similar. CONCLUSIONS: CAD patients with AF are at a higher risk of subsequent MI than of stroke. Among those with CVD, the risk of stroke far exceeds that of MI. Those with PAD have a high and similar risk for both events.