CCR5 deficiency impairs CD4+ T-cell memory responses and antigenic sensitivity through increased ceramide synthesis.

CCR5 is not only a coreceptor for HIV-1 infection in CD4+ T cells, but also contributes to their functional fitness. Here, we show that by limiting transcription of specific ceramide synthases, CCR5 signaling reduces ceramide levels and thereby increases T-cell antigen receptor (TCR) nanoclustering in antigen-experienced mouse and human CD4+ T cells. This activity is CCR5-specific and independent of CCR5 co-stimulatory activity. CCR5-deficient mice showed reduced production of high-affinity class-switched antibodies, but only after antigen rechallenge, which implies an impaired memory CD4+ T-cell response. This study identifies a CCR5 function in the generation of CD4+ T-cell memory responses and establishes an antigen-independent mechanism that regulates TCR nanoclustering by altering specific lipid species.

Response to glecaprevir/pibrentasvir in HIV/HCV-coinfected patients in clinical practice.

OBJECTIVES: HIV infection has been associated with lower rates of sustained viral response (SVR) with direct-acting antivirals (DAAs). There are few data on glecaprevir/pibrentasvir (G/P) in HIV/HCV coinfection outside clinical trials. METHODS: The HEPAVIR-DAA cohort, which recruits HIV/HCV-coinfected patients (NCT02057003) and the GEHEP-MONO cohort (NCT02333292), including HCV-monoinfected individuals, are two concurrent ongoing multicentre cohorts of patients receiving anti-HCV treatment. Patients starting G/P included in those cohorts were analysed. Overall SVR (ITT), discontinuations due to adverse effects, and dropouts were evaluated and compared between both cohorts. RESULTS: Of the 644 patients who started G/P with evaluable SVR, 132 were HIV/HCV coinfected. Overall SVR rates were 487/512 (95.1%) in HCV-monoinfected patients versus 126/132 (95.5%) in HIV/HCV-coinfected patients (P = 1.000). One patient (0.8%) relapsed, and another (0.8%) discontinued treatment due to side effects. SVR to 8 or 12 weeks of treatment with G/P was similar in HIV/HCV-coinfected versus HCV-monoinfected patients. The main reason for not reaching SVR among HIV/HCV-coinfected patients was premature dropout linked to active drug use. CONCLUSIONS: G/P in HIV/HCV coinfection was highly effective and tolerable in clinical practice. SVR to 8 or 12 weeks of treatment with G/P was similar in HIV/HCV-coinfected compared with HCV-monoinfected patients but active drug use is still a barrier to reach HCV microelimination.

Immunological and senescence biomarker profiles in patients after spontaneous clearance of hepatitis C virus: gender implications for long-term health risk.

BACKGROUND: About 25% of patients with acute hepatitis C virus (HCV) infection show spontaneous clearance within the first six months of infection but may remain at risk of inflammaging, aging, and liver and non-liver disease complications. This study evaluated the differences in the plasma levels of immune checkpoints (ICs) and senescence-associated secretory phenotype (SASP) biomarkers between patients who had spontaneously eliminated HCV infection (SC group) and individuals without evidence of HCV infection (C group). METHODS: We performed a multicenter retrospective study of 56 individuals: 32 in the SC and 24 in the C groups. ICs and SASP proteins were analyzed using a Luminex 200TM analyzer. The statistical analysis used Generalized Linear Models with gamma distribution (log-link) adjusted by significant variables and sex. RESULTS: 13 ICs (BTLA, CD137(4-1BB), CD27, CD28, CD80, GITR, HVEM, IDO, LAG-3, PD-1, PD-L1, PD-L2, and TIM-3) and 13 SASP proteins (EGF, Eotaxin, IL-1alpha, IL-1RA, IL-8, IL-13, IL-18, IP-10, SDF-1alpha, HGF, beta-NGF, PLGF-1, and SCF) were significantly higher in SC group after approximately more than two years of HCV clearance. After stratifying by sex, differences remained significant for males, which showed higher levels for 13 ICs and 4 SASP proteins in SC. While only PD-L2 was significantly higher in SC women, and no differences in SASP were found. CONCLUSIONS: Higher plasma levels of different IC and SASP proteins were found in individuals after more than two years of HCV clearance, mainly in men. Alterations in these molecules might be associated with an increased risk of developing liver and non-hepatic diseases.

A Functional Pipeline of Genome-Wide Association Data Leads to Midostaurin as a Repurposed Drug for Alzheimer's Disease.

Genome-wide association studies (GWAS) constitute a powerful tool to identify the different biochemical pathways associated with disease. This knowledge can be used to prioritize drugs targeting these routes, paving the road to clinical application. Here, we describe DAGGER (Drug Repositioning by Analysis of GWAS and Gene Expression in R), a straightforward pipeline to find currently approved drugs with repurposing potential. As a proof of concept, we analyzed a meta-GWAS of 1.6 × 107 single-nucleotide polymorphisms performed on Alzheimer's disease (AD). Our pipeline uses the Genotype-Tissue Expression (GTEx) and Drug Gene Interaction (DGI) databases for a rational prioritization of 22 druggable targets. Next, we performed a two-stage in vivo functional assay. We used a C. elegans humanized model over-expressing the Aß1-42 peptide. We assayed the five top-scoring candidate drugs, finding midostaurin, a multitarget protein kinase inhibitor, to be a protective drug. Next, 3xTg AD transgenic mice were used for a final evaluation of midostaurin's effect. Behavioral testing after three weeks of 20 mg/kg intraperitoneal treatment revealed a significant improvement in behavior, including locomotion, anxiety-like behavior, and new-place recognition. Altogether, we consider that our pipeline might be a useful tool for drug repurposing in complex diseases.

Mendelian Randomisation Confirms the Role of Y-Chromosome Loss in Alzheimer's Disease Aetiopathogenesis in Men.

Mosaic loss of chromosome Y (mLOY) is a common ageing-related somatic event and has been previously associated with Alzheimer's disease (AD). However, mLOY estimation from genotype microarray data only reflects the mLOY degree of subjects at the moment of DNA sampling. Therefore, mLOY phenotype associations with AD can be severely age-confounded in the context of genome-wide association studies. Here, we applied Mendelian randomisation to construct an age-independent mLOY polygenic risk score (mloy-PRS) using 114 autosomal variants. The mloy-PRS instrument was associated with an 80% increase in mLOY risk per standard deviation unit (p = 4.22 × 10-20) and was orthogonal with age. We found that a higher genetic risk for mLOY was associated with faster progression to AD in men with mild cognitive impairment (hazard ratio (HR) = 1.23, p = 0.01). Importantly, mloy-PRS had no effect on AD conversion or risk in the female group, suggesting that these associations are caused by the inherent loss of the Y chromosome. Additionally, the blood mLOY phenotype in men was associated with increased cerebrospinal fluid levels of total tau and phosphorylated tau181 in subjects with mild cognitive impairment and dementia. Our results strongly suggest that mLOY is involved in AD pathogenesis.

Human Immunodeficiency Virus (HIV) Infection Is Associated With Lower Risk of Hepatocellular Carcinoma After Sustained Virological Response to Direct-acting Antivirals in Hepatitis C Infected Patients With Advanced Fibrosis.

BACKGROUND: The aim of this study was to assess the impact of human immunodeficiency virus (HIV) infection on the risk of developing hepatocellular carcinoma (HCC) in patients infected with hepatitis C virus (HCV) who achieve sustained virological response (SVR) with direct-acting antiviral (DAA). METHODS: Multisite prospective cohort study, where HCV-monoinfected patients and HIV/HCV-coinfected individuals were included if they met: (1) SVR with DAA-based combination; (2) liver stiffness (LS) ≥9.5 kPa previous to treatment; (3) LS measurement at the SVR time-point. The main endpoint was the occurrence of HCC. Propensity score (PS) was calculated to address potential confounders due to unbalanced distribution of baseline characteristics of HIV/HCV-coinfected and HCV-monoinfected patients. RESULTS: In total, 1035 HCV-infected patients were included, 667 (64%) coinfected with HIV. After a median (Q1-Q3) follow-up time of 43 (31-49) months, 19 (1.8%) patients developed HCC (11 [3.0%]; HCV-monoinfected, 8[1.2%]; HIV/HCV-coinfected individuals; P = .013). In the multivariable analysis, HIV coinfection was associated with a lower adjusted risk of developing HCC (subhazard ratio [sHR] = 0.27, 95% confidence interval [CI]: .08-.90; P = .034). Predictors of HCC emergence were: HCV genotype 3 (sHR = 7.9, 95% CI: 2.5-24.9; P < .001), MELD score at SVR >10 (sHR = 1.37, 95% CI: 1.01-1.86; P = .043) and LS value at SVR (sHR = 1.03, 95% CI: 1.01-1.06, for 1 kPa increase; P = .011). Using inverse probability weighting method on the PS, HIV-infected patients had a lower risk of HCC (powered HR = 0.33, 95% CI: .11-.85). CONCLUSIONS: Among HCV-infected patients with advanced fibrosis, who achieve SVR with DAA, HIV coinfection seems to be associated with a lower risk of HCC occurrence. The underlying causes for this finding need to be investigated.

Liver Stiffness-Based Strategies Predict Absence of Variceal Bleeding in Cirrhotic Hepatitis C Virus-Infected Patients With and Without Human Immunodeficiency Virus Coinfection After Sustained Virological Response.

BACKGROUND: In the setting of hepatitis C virus (HCV) active infection, liver stiffness (LS)-based strategies identify patients with low risk of developing esophageal variceal bleeding (VB) episodes, in whom unnecessary upper esophagogastroduodenoscopy (UGE) screening can be safely avoided. However, after sustained virological response (SVR), data on the accuracy of the criteria predicting this outcome in HCV-infected patients with cirrhosis, with or without human immunodeficiency virus (HIV) coinfection, are very limited. METHODS: This was a multicenter prospective cohort study, where HCV-monoinfected patients and HIV/HCV-coinfected individuals were included if they had (1) SVR with direct-acting antiviral-based therapy; (2) LS ≥9.5 kPa previous to treatment; and (3) LS measurement at the SVR time-point ≥14 kPa. Diagnostic accuracy of HEPAVIR, expanded Baveno VI, and HIV cirrhosis criteria, at the time of SVR, was evaluated. Missed VB episodes, negative predictive values (NPVs), and number of spared UGEs were specifically assessed. RESULTS: Four hundred thirty-five patients were included, 284 (65%) coinfected with HIV. Seven (1.6%) patients developed a first episode of VB after SVR. In patients without a previous VB episode, HEPAVIR, expanded Baveno VI and HIV cirrhosis criteria achieved NPV for first VB episode after SVR of 99.5% (95% confidence interval [CI], 97.1%-100%), 100% (95% CI 97.8%-100%), and 100% (95% CI 98%-100%) while sparing 45%, 39%, and 44% of UGEs, respectively. When considering HIV coinfection, the performance of the 3 criteria was similar, both in HCV-monoinfected and HIV/HCV-coinfected individuals. CONCLUSIONS: After SVR, predictive LS-based strategies accurately identify HCV-infected patients, HIV coinfected or not, with low risk of developing VB during follow-up. In these specific patients, using HIV cirrhosis criteria maximize the number of spared UGEs while missing no VB episode.

Toll-Like Receptor 2 Promoter -196 to -174 Deletion Affects CD4 Levels Along Human Immunodeficiency Virus Infection Progression.

Toll-like receptor 2 (TLR2) plays a key role in innate immune response recognizing molecular patterns expressed by pathogens. rs111200466 is a TLR2 promoter insertion/deletion polymorphism with contradictory data about its role in human immunodeficiency virus type 1 (HIV-1) infection. We analyzed rs111200466 in HIV-1 disease progression and showed a correlation with a faster progression to the CD4+ < 200 cells/µL outcome for deletion allele carriers (Cox regression analysis: hazard ratio, 2.4 [95% confidence interval, 1.4-4]; P = .001). When naive patients with CD4+ < 200 cells/µL started antiretroviral treatment, rs111200466-deletion carriers showed a trend toward a slower, recovery rate (time required to reach CD4+ > 350 cells/µL; Cox P = .36). Our data suggest rs111200466 as a prognosis factor for HIV-1 disease progression.

The Ubiquitin Proteasome System in Neuromuscular Disorders: Moving Beyond Movement.

Neuromuscular disorders (NMDs) affect 1 in 3000 people worldwide. There are more than 150 different types of NMDs, where the common feature is the loss of muscle strength. These disorders are classified according to their neuroanatomical location, as motor neuron diseases, peripheral nerve diseases, neuromuscular junction diseases, and muscle diseases. Over the years, numerous studies have pointed to protein homeostasis as a crucial factor in the development of these fatal diseases. The ubiquitin-proteasome system (UPS) plays a fundamental role in maintaining protein homeostasis, being involved in protein degradation, among other cellular functions. Through a cascade of enzymatic reactions, proteins are ubiquitinated, tagged, and translocated to the proteasome to be degraded. Within the ubiquitin system, we can find three main groups of enzymes: E1 (ubiquitin-activating enzymes), E2 (ubiquitin-conjugating enzymes), and E3 (ubiquitin-protein ligases). Only the ubiquitinated proteins with specific chain linkages (such as K48) will be degraded by the UPS. In this review, we describe the relevance of this system in NMDs, summarizing the UPS proteins that have been involved in pathological conditions and neuromuscular disorders, such as Spinal Muscular Atrophy (SMA), Charcot-Marie-Tooth disease (CMT), or Duchenne Muscular Dystrophy (DMD), among others. A better knowledge of the processes involved in the maintenance of proteostasis may pave the way for future progress in neuromuscular disorder studies and treatments.

Genetic Association Studies in Host-Pathogen Interaction Analysis.

Studying host-pathogen interactions at a molecular level has always been technically challenging. Identifying the different biochemical and genetic pathways involved in the different stages of infection traditionally require complex molecular biology tools and often the use of costly animal models. In this chapter, we illustrate a complementary approach to address host-pathogen interactions, taking advantage of the natural interindividual genetic diversity. The application of genetic association studies allows us to identify alleles involved in infection progression or resistance. Thus, this strategy may be useful to unravel new molecular pathways underlying host-pathogen interactions. Here we present the general steps that might be followed to plan, execute, and analyze a population-based study in order to identify genetic variants affecting human exposition to pathogens.

The absence of seroconversion after exposition to hepatitis C virus is not related to KIR-HLA genotype combinations (GEHEP-012 study).

BACKGROUND & AIMS: It has been reported that specific killer-cell immunoglobulin-like receptors (KIRs) and HLA genotype combinations, such as KIR2DS4/HLA-C1 with presence of KIRDL2 or KIRDL3, homozygous KIRDL3/HLA-C1 and KIR3DL1/≥2HLA-Bw4, are strongly associated with the lack of active infection and seroconversion after exposition to hepatitis C virus (HCV). OBJECTIVE: To determine whether these KIR-HLA combinations are relevant factors involved in that phenotype. PATIENTS AND METHODS: In this retrospective case-control study, genotype data from a genome-wide association study previously performed on low susceptibility to HCV-infection carried out on 27 high-risk HCV-seronegative (HRSN) individuals and 743 chronically infected (CI) subjects were used. HLA alleles were imputed using R package HIBAG v1.2223 and KIR genotypes were imputed using the online resource KIR*IMP v1.2.0. RESULTS: It was possible to successfully impute at least one KIR-HLA genotype combination previously associated with the lack of infection and seroconversion after exposition to HCV in a total of 23 (85.2%) HRSN individuals and in 650 (87.5%) CI subjects. No KIR-HLA genotype combination analyzed was related to the HRSN condition. CONCLUSIONS: Our results suggest that those KIR-HLA genotype combinations are not relevant factors involved in the lack of infection and seroconversion after exposition to HCV. More studies will be needed to completely understand this phenotype.

Connecting genomic and proteomic signatures of amyloid burden in the brain.

Background: Alzheimer's disease (AD) has a high heritable component characteristic of complex diseases, yet many of the genetic risk factors remain unknown. We combined genome-wide association studies (GWAS) on amyloid endophenotypes measured in cerebrospinal fluid (CSF) and positron emission tomography (PET) as surrogates of amyloid pathology, which may be helpful to understand the underlying biology of the disease. Methods: We performed a meta-analysis of GWAS of CSF Aß42 and PET measures combining six independent cohorts (n=2,076). Due to the opposite effect direction of Aß phenotypes in CSF and PET measures, only genetic signals in the opposite direction were considered for analysis (n=376,599). Polygenic risk scores (PRS) were calculated and evaluated for AD status and amyloid endophenotypes. We then searched the CSF proteome signature of brain amyloidosis using SOMAscan proteomic data (Ace cohort, n=1,008) and connected it with GWAS results of loci modulating amyloidosis. Finally, we compared our results with a large meta-analysis using publicly available datasets in CSF (n=13,409) and PET (n=13,116). This combined approach enabled the identification of overlapping genes and proteins associated with amyloid burden and the assessment of their biological significance using enrichment analyses. Results: After filtering the meta-GWAS, we observed genome-wide significance in the rs429358-APOE locus and nine suggestive hits were annotated. We replicated the APOE loci using the large CSF-PET meta-GWAS and identified multiple AD-associated genes as well as the novel GADL1 locus. Additionally, we found a significant association between the AD PRS and amyloid levels, whereas no significant association was found between any Aß PRS with AD risk. CSF SOMAscan analysis identified 1,387 FDR-significant proteins associated with CSF Aß42 levels. The overlap among GWAS loci and proteins associated with amyloid burden was very poor (n=35). The enrichment analysis of overlapping hits strongly suggested several signalling pathways connecting amyloidosis with the anchored component of the plasma membrane, synapse physiology and mental disorders that were replicated in the large CSF-PET meta-analysis. Conclusions: The strategy of combining CSF and PET amyloid endophenotypes GWAS with CSF proteome analyses might be effective for identifying signals associated with the AD pathological process and elucidate causative molecular mechanisms behind the amyloid mobilization in AD.

An Insertion Within SIRPß1 Shows a Dual Effect Over Alzheimer's Disease Cognitive Decline Altering the Microglial Response.

Background: Microglial dysfunction plays a causative role in Alzheimer's disease (AD) pathogenesis. Here we focus on a germline insertion/deletion variant mapping SIRPß1, a surface receptor that triggers amyloid-ß(Aß) phagocytosis via TYROBP. Objective: To analyze the impact of this copy-number variant in SIRPß1 expression and how it affects AD molecular etiology. Methods: Copy-number variant proxy rs2209313 was evaluated in GERALD and GR@ACE longitudinal series. Hippocampal specimens of genotyped AD patients were also examined. SIRPß1 isoform-specific phagocytosis assays were performed in HEK393T cells. Results: The insertion alters the SIRPß1 protein isoform landscape compromising its ability to bind oligomeric Aß and its affinity for TYROBP. SIRPß1 Dup/Dup patients with mild cognitive impairment show an increased cerebrospinal fluid t-Tau/Aß ratio (p = 0.018) and a higher risk to develop AD (OR = 1.678, p = 0.018). MRIs showed that Dup/Dup patients exhibited a worse initial response to AD. At the moment of diagnosis, all patients showed equivalent Mini-Mental State Examination scores. However, AD patients with the duplication had less hippocampal degeneration (p < 0.001) and fewer white matter hyperintensities. In contrast, longitudinal studies indicate that patients bearing the duplication allele show a slower cognitive decline (p = 0.013). Transcriptional analysis also shows that the SIRPß1 duplication allele correlates with higher TREM2 expression and an increased microglial activation. Conclusions: The SIRPß1 internal duplication has opposite effects over MCI-to-Dementia conversion risk and AD progression, affecting microglial response to Aß. Given the pharmacological approaches focused on the TREM2-TYROBP axis, we believe that SIRPß1 structural variant might be considered as a potential modulator of this causative pathway.

Hepatic steatosis after switching to integrase inhibitor-based regimens does not parallel short-term weight gain.

We studied hepatic steatosis in people with HIV (PWH) who switched to an integrase inhibitor (INSTI)-based regimen. One hundred and fifty-four PWH were included. After 48 weeks, median (Q1-Q3) weight gain was 1.2 (-0.6 to 3.8) kg and median (Q1-Q3) controlled attenuation parameter (CAP) change was -4 (-33 to 27) dB/m. Weight gain was weakly correlated with CAP change [R2 95% confidence interval (CI) = 0.144 (-0.014 to 0.296); P = 0.074)]. Changes in hepatic steatosis after switching to INSTI-based regimens do not seem to parallel weight gain after 1 year.

Hepatic Steatosis and Weight Gain During the Coronavirus Disease 2019 Pandemic Among People With Human Immunodeficiency Virus: Impact of Therapy With Tenofovir Alafenamide.

Background: Lockdown due to the coronavirus disease 2019 (COVID-19) pandemic led to increases in weight in part of the population. Weight gain leads to hepatic steatosis (HS). Antiretroviral treatment could also influence HS in people with human immunodeficiency virus (PWH). The impact of lockdown on HS in PWH is unknown. The aim of this study was to analyze the changes in HS, as measured by the controlled attenuation parameter (CAP), during the COVID-19 pandemic in PWH. Methods: This was a cohort study that included PWH who attended a tertiary care center in southern Spain from January 2018 to December 2021. The CAP was evaluated by transient elastography. Only those who had a valid CAP before and after March 2020 were included. HS was defined as CAP ≥248 dB/m. Results: Six hundred eighty PWH were attended and 488 (71.8%) were included. Two hundred and fourteen (43.9%) had HS at baseline and 239 (49%) at the end of the follow-up (P = .036). The median change in CAP among PWH taking tenofovir alafenamide (TAF) was 8.5 (interquartile range [IQR], -24 to 46.3) dB/m versus -4 (IQR, -35 to 27) dB/m among PWH receiving TAF-free regimens (P = .003). After multivariate analysis, adjusted by sex and age, weight gain (adjusted odds ratio [AOR], 1.09 [95% confidence interval {CI}, 1.05-1.14]; P < .001), TAF therapy (AOR, 1.59 [95% CI, 1.07-2.35]; P = .021), plasma triglycerides (AOR, 1.01 [95% CI, 1-1.01]; P < .001), and fasting blood glucose (AOR, 1.01 [95% CI, 1-1.02]; P = .027) were associated with HS at the end of follow-up. Conclusions: The frequency of HS increased during the COVID-19 pandemic among PWH. TAF is associated with HS development, regardless of metabolic factors.

A metagenome-wide association study of HIV disease progression in HIV controllers.

Some HIV controllers experience immunologic progression with CD4+ T cell decline. We aimed to identify genetic factors associated with CD4+ T cell lost in HIV controllers. A total of 561 HIV controllers were included, 442 and 119 from the International HIV controllers Study Cohort and the Swiss HIV Cohort Study, respectively. No SNP or gene was associated with the long-term non-progressor HIV spontaneous control phenotype in the individual GWAS or in the meta-analysis. However, SNPs previously associated with natural HIV control linked to HLA-B (rs2395029 [p = 0.005; OR = 1.70], rs59440261 [p = 0.003; OR = 1.78]), MICA (rs112243036 [p = 0.011; OR = 1.45]), and PSORS1C1 loci (rs3815087 [p = 0.017; OR = 1.39]) showed nominal association with this phenotype. Genetic factors associated with the long-term HIV controllers without risk of immunologic progression are those previously related to the overall HIV controller phenotype.

IFNL4 genotype influences the rate of HIV-1 seroconversion in men who have sex with men.

Individuals lacking interferon lambda 4 (IFNL4) protein due to a common null mutation (rs368234815) in the IFNL4 gene display higher resistance against several infections. The influence of IFNL4 on HIV-1 infection is still under discussion and conflicting results have been reported. This study intended to corroborate or refute the association of the null allele of IFNL4 and HIV-1 predisposition in a cohort of men who have sex with men (MSM). IFNL4 null genotype was assessed on 619 HIV-1-seronegative MSM who were followed for 36 months during a trial of a prophylactic vaccine against HIV-1. Of those, 257 individuals seroconverted during this period. A logistic regression model was constructed including demographic and IFNL4 genotype. In addition, a meta-analysis using data from the current study and other European populations was conducted. The null IFNL4 genotypes were correlated with lower HIV-1 seroconversion (Adjusted OR = 0.4 [95%CI: 0.2-0.8], P = 0.008) and longer time to seroconversion (889 vs. 938 days, P= 0.01). These results were validated by a meta-analysis incorporating data from other European populations and the result yielded a significant association of the IFNL4 null genotype under a dominant model with a lower probability of HIV-1 infection (OR=0.4 [95% CI: 0.3-0.6]; P= 1.3 x 10E-5).

No association of a risk variant for severe COVID-19 with HIV protection in three cohorts of highly exposed individuals.

An extended haplotype on chromosome 3 is the major genetic risk factor for severe COVID-19. The risk haplotype, which was inherited from Neanderthals, decreases the expression of several cytokine receptors, including CCR5. Recently, a study based on three general population cohorts indicated that the minor allele of one of the variants in the haplotype (rs17713054) protects against HIV infection. We thus expected this allele to be over-represented in highly exposed individuals who remain uninfected (exposed seronegative individuals, ESN). To perform a meta-analysis, we genotyped rs17713054 in three ESN cohorts of European ancestry exposed to HIV through different routes. No evidence of association was detected in the single cohorts. The meta-analysis also failed to detect any effect of the variant on protection from HIV-1. The same results were obtained in a Cox-regression analysis for the time to seroconversion. An in-vitro infection assay did not detect differences in viral replication as a function of rs17713054 genotype status. We conclude that the rs17713054 minor allele is not associated with the ESN phenotype and does not modulate HIV infection in vitro.

Controlled attenuation parameter-insulin resistance (CIR) score to predict non-alcoholic steatohepatitis.

The diagnosis of non-alcoholic steatohepatitis (NASH) requires liver biopsy. Patients with NASH are at risk of progression to advanced fibrosis and hepatocellular carcinoma. A reliable non-invasive tool for the detection of NASH is needed. We aimed at developing a tool to diagnose NASH based on a predictive model including routine clinical and transient hepatic elastography (TE) data. All subjects undergoing elective cholecystectomy in our center were invited to participate, if alcohol intake was < 30 g/d for men and < 15 g/d for women. TE with controlled attenuation parameter (CAP) was obtained before surgery. A liver biopsy was taken during surgery. Multivariate logistic regression models to predict NASH were constructed with the first 100 patients, the elaboration group, and the results were validated in the next pre-planned 50 patients. Overall, 155 patients underwent liver biopsy. In the elaboration group, independent predictors of NASH were CAP value [adjusted OR (AOR) 1.024, 95% confidence interval (95% CI) 1.002-1.046, p = 0.030] and HOMA value (AOR 1.847, 95% CI 1.203-2.835, p < 0.001). An index derived from the logistic regression equation to identify NASH was designated as the CAP-insulin resistance (CIR) score. The area under the receiver operating characteristic curve (95%CI) of the CIR score was 0.93 (0.87-0.99). Positive (PPV) and negative predictive values (NPV) of the CIR score were 82% and 91%, respectively. In the validation set, PPV was 83% and NPV was 88%. In conclusion, the CIR score, a simple index based on CAP and HOMA, can reliably identify patients with and without NASH.

CD46 Genetic Variability and HIV-1 Infection Susceptibility.

CD46 is the main receptor for complement protein C3 and plays an important role in adaptive immune responses. CD46 genetic variants are associated with susceptibility to several infectious and autoimmune diseases. Additionally, CD46 function can be subverted by HIV-1 to evade attack by complement, a strategy shared by viruses of other families. We sought to determine the association between CD46 gene variants and HIV-1 acquired through intravenous drug use (IDU) and sexual routes (n = 823). Study subjects were of European ancestry and were HIV-1 infected (n = 438) or exposed but seronegative (n = 387). Genotyping of the rs2796265 SNP located in the CD46 gene region was done by allele-specific real-time PCR. A meta-analysis merging IDU and sexual cohorts indicates that the minor genotype (CC) was associated with increased resistance to HIV-1 infection OR = 0.2, 95% CI (0.07-0.61), p = 0.004. The HIV-1-protective genotype is correlated with reduced CD46 expression and alterations in the ratio of CD46 mRNA splicing isoforms.