Immunological status does not influence hepatitis c virus or liver fibrosis in HIV-hepatitis C virus-coinfected patients

TANGO1 Dances to Export of Procollagen from the Endoplasmic Reticulum

The endoplasmic reticulum (ER) to Golgi secretory pathway is an elegantly complex process whereby protein cargoes are manufactured, folded, and distributed from the ER to the cisternal layers of the Golgi stack before they are delivered to their final destinations. The export of large bulky cargoes such as procollagen and its trafficking to the Golgi is a sophisticated mechanism requiring TANGO1 (Transport ANd Golgi Organization protein 1. It is also called MIA3 (Melanoma Inhibitory Activity protein 3). TANGO1 has two prominent isoforms, TANGO1-Long and TANGO1-Short, and each isoform has specific functions. On the luminal side, TANGO1-Long has an HSP47 recruitment domain and uses this protein to collect collagen. It can also tether its paralog isoforms cTAGE5 and TALI and along with these proteins enlarges the vesicle to accommodate procollagen. Recent studies show that TANGO1-Long combines retrograde membrane flow with anterograde cargo transport. This complex mechanism is highly activated in fibrosis and promotes the excessive deposition of collagen in the tissues. The therapeutic targeting of TANGO1 may prove successful in the control of fibrotic disorders. This review focuses on TANGO1 and its complex interaction with other procollagen export factors that modulate increased vesicle size to accommodate the export of procollagen.

Alcohol Consumption and Risk of Liver Fibrosis in People Living With HIV: A Systematic Review and Meta-Analysis

Objectives

It is unclear if a high level of alcohol consumption is a risk factor for liver fibrosis for people living with HIV (PLWH). This study systematically summarizes the risk relationship between different alcohol consumption and the incidence of liver fibrosis among PLWH.

Methods

We identified potential studies by searching the PubMed, Embase, Web of Science Library, and CNKI databases up to September 26th, 2021. Observation studies in PLWH that evaluated the relationship between alcohol consumption and the risk of liver fibrosis and estimated the effect of alcohol with pooled odds ratios (pooled ORs) and 95% confidence intervals (CIs) were included.

Results

There were total 15 studies included in data analysis. Three studies were set up as cohort studies and the other twelve were cross-sectional studies. Our study was based on 22,676 individuals and 2,729 liver fibrosis cases from 15 studies. Alcohol abuse is a significant risk factor of liver fibrosis (pooled OR = 2.25, 95% CI: 1.59-3.17, p < 0.05) among PLWH. Daily alcohol consumption > 50 g can elevate the risk of liver fibrosis (pooled OR = 3.10, 95% CI: 2.02-4.73, p < 0.05) among PLWH. However, high-risk alcohol consumption determined by AUDIT-C (AUDIT-C ≥ 4) had little or no effect on subsequent liver fibrosis risk. Further, alcohol consumption > 50 g is also a risk factor to liver fibrosis in PLWH co-infected with HCV (pooled OR = 2.48, 95% CI: 1.62-3.80, p < 0.05) and in HIV mono-infected (pooled OR = 1.85, 95% CI: 1.00-3.43, p < 0.05).

Conclusion

Alcohol consumption is associated with an increased risk of liver fibrosis in PLWH. HCV co-infection with alcohol abuse could possibly induce a higher risk of liver fibrosis than HIV mono-infected patients.

Systematic Review Registration

PROSPERO, identifier (CRD42021272604).

Clinical Liver Disease Progression Among Hepatitis C-Infected Drug Users With CD4 Cell Count Less Than 200 Cells/mm(3) Is More Pronounced Among Women Than Men

The rate of clinical liver disease progression in this cohort of HCV mono-infected and HIV/HCV co-infected individuals was higher than previously reported. Risk of clinical liver disease progression was associated with level of immune suppression, and was more pronounced in women.

Background. Hepatitis C virus (HCV) infection is a leading cause of liver-related morbidity and mortality in the United States, and injection drug users are at particularly high risk.

Methods. This prospective observational cohort study assessed the rate of, and risk factors for, clinical liver disease progression in a cohort of HCV monoinfected and human immunodeficiency virus (HIV)/HCV coinfected drug users using unadjusted and multivariate Cox proportional hazards regression analyses.

Results. Of 564 subjects including 421 (75%) with HIV/HCV coinfection and 143 with HCV monoinfection, 55 (10%) had clinical liver disease progression during follow-up with a rate of 25.3 events per 1000 person-years. In unadjusted analysis, there was an interaction between sex and HIV status. In sex-stratified multivariate analysis, HIV/HCV-coinfected women with CD4 <200 cells/mm³ had 9.99 times the risk of liver disease progression as HCV-monoinfected women (confidence interval [CI], 1.84–54.31; P = .008), and white women had a trend towards increased risk of liver disease progression compared with non-white women (hazard ratio, 2.84; CI, .93–8.68; P = .07). Human immunodeficiency virus/HCV-coinfected men with CD4 <200 cells/mm³ had 2.86 times the risk of liver disease progression as HCV-monoinfected men (CI, 1.23-6.65; P = .01).

Conclusions. Hepatitis C virus-monoinfected and HIV/HCV-coinfected drug users had high rates of clinical liver disease progression. In those with HIV infection, liver disease progression was associated with advanced immune suppression. This effect was strikingly more pronounced in women than in men.

Liver fibrosis in human immunodeficiency virus/hepatitis C virus coinfection: Diagnostic methods and clinical impact

Several non-invasive surrogate methods have recently challenged the main role of liver biopsy in assessing liver fibrosis in hepatitis C virus (HCV)-monoinfected and human immunodeficiency virus (HIV)/HCV-coinfected patients, applied to avoid the well-known side effects of liver puncture. Serological tests involve the determination of biochemical markers of synthesis or degradation of fibrosis, tests not readily available in clinical practice, or combinations of routine tests used in chronic hepatitis and HIV/HCV coinfection. Several radiologic techniques have also been proposed, some of which commonly used in clinical practice. The studies performed to compare the prognostic value of non-invasive surrogate methods with that of the degree of liver fibrosis assessed on liver tissue have not as yet provided conclusive results. Each surrogate technique has shown some limitations, including the risk of over- or under-estimating the extent of liver fibrosis. The current knowledge on liver fibrosis in HIV/HCV-coinfected patients will be summarized in this review article, which is addressed in particular to physicians involved in this setting in their clinical practice.

CD4 recovery on antiretroviral therapy is associated with decreased progression to liver disease among hepatitis C virus-infected injecting drug users

Background.  Human immunodeficiency virus (HIV) coinfection accelerates liver disease progression in individuals with chronic hepatitis C. We evaluated the associations of CD4, HIV RNA, and antiretroviral therapy (ART)-induced CD4 recovery with liver diagnoses in a prospective cohort of injecting drug users (IDUs). Methods.  We evaluated 383 coinfected IDUs in the Boston area, prospectively observed for a median of 1.8 years. Liver disease progression included the first occurrence of hepatocellular carcinoma, variceal bleeding, ascites, encephalopathy, or death due to hepatic failure. Multivariable-adjusted extended Cox models were specified to estimate hazard ratios (HRs) for comparisons of CD4, change in CD4 (from nadir), and HIV RNA with respect to liver disease progression events. Results.  Twenty-four persons experienced a liver disease progression event over 1155 person-years (2.1 per 100 person-years), including 20 deaths attributed to end-stage liver disease (1.7 per 100 person-years). CD4 at baseline and over follow-up strongly predicted liver disease progression (baseline CD4 <200 vs ≥200: HR = 5.23, 95% confidence interval [CI], 2.30-11.92; time-updated CD4 <200 vs ≥200: HR = 11.79, 95% CI, 4.47-31.07). Nadir CD4 was also a strong indicator (<100 vs ≥100: HR = 3.52, 95% CI, 1.54-8.06). A lack of CD4 recovery (failure to increase 100 cells over nadir) among ART initiators was associated with increased risk (HR = 7.69; 95% CI, 2.60-22.69). Human immunodeficiency virus RNA was not significantly associated with liver disease progression. Conclusions.  Impaired immune function was highly predictive of liver disease progression in this cohort of IDUs, and a lack of CD4 recovery on ART was associated with increased risk of progression to HCV-associated liver disease.

Antiretroviral therapy reduces the rate of hepatic decompensation among HIV- and hepatitis C virus-coinfected veterans

BACKGROUND

 Human immunodeficiency virus (HIV) coinfection accelerates the rate of liver disease outcomes in individuals chronically infected with hepatitis C virus (HCV). It remains unclear to what degree combination antiretroviral therapy (ART) protects against HCV-associated liver failure.

METHODS

 We evaluated 10 090 HIV/HCV-coinfected males from the Veterans Aging Cohort Study Virtual Cohort, who had not initiated ART at entry, for incident hepatic decompensation between 1996 and 2010. We defined ART initiation as the first pharmacy fill date of a qualifying ART regimen of ≥3 drugs from ≥2 classes. Hepatic decompensation was defined as the first occurrence of 1 hospital discharge diagnosis or 2 outpatient diagnoses for ascites, spontaneous bacterial peritonitis, or esophageal variceal hemorrhage. To account for potential confounding by indication, marginal structural models were used to estimate hazard ratios (HRs) of hepatic decompensation, comparing initiation of ART to noninitiation.

RESULTS

 We observed 645 hepatic decompensation events in 46 444 person-years of follow-up (incidence rate, 1.4/100 person-years). Coinfected patients who initiated ART had a significantly reduced rate of hepatic decompensation relative to noninitiators (HR = 0.72; 95% confidence interval [CI], .54-.94). When we removed individuals with HIV RNA ≤400 copies/mL at baseline from the analysis (assuming that they may have received undocumented ART at entry), the hazard ratio became more pronounced (HR = 0.59; 95% CI, .43-.82).

CONCLUSIONS

 Initiation of ART significantly reduced the rate of hepatic decompensation by 28%-41% on average. These results suggest that ART should be administered to HIV/HCV-coinfected patients to lower the risk of end-stage liver disease.

HIV-1 tropism and liver fibrosis in HIV-HCV co-infected patients

Background and Aims

Hepatic stellate cells, the major producers of extracellular matrix in the liver, and hepatocytes bear CXCR4 and CCR5, the two main co-receptors for entry of the human immunodeficiency virus (HIV). In vitro studies suggest that HIV-envelope proteins can modulate the replication of hepatitis C virus (HCV) and fibrogenesis. We investigated the influence of HIV tropism on liver fibrosis and the concentration of HCV RNA in HIV–HCV co-infected patients.

Methods

We used a phenotypic assay to assess HIV tropism in 172 HCV–HIV co-infected patients: one group (75 patients) had mild fibrosis (score ≤F2) and the other (97 patients) had severe fibrosis (score >F2). We also assessed the relationship between HIV tropism and HCV RNA concentration in all these patients. We also followed 34 of these patients for 3 years to determine the evolution of HIV tropism and liver fibrosis, estimated by liver stiffness.

Results

Initially, most patients (91.8%) received a potent antiretroviral therapy. CXCR4-using viruses were found in 29% of patients. The only factor associated with a CXCR4-using virus infection in multivariate analysis was the nadir of CD4 cells: <200/mm³ (OR: 3.94, 95%CI: 1.39–11.14). The median HCV RNA concentrations in patients infected with R5 viruses, those with dual-mixed viruses and those with X4 viruses, were all similar. The prevalence of CXCR4-using viruses in patients with mild fibrosis (≤F2) (31%) and those with severe fibrosis (F3–F4) (28%, p = 0.6) was similar. Longitudinal analyses showed that the presence of CXCR4-using viruses did not increase the likelihood of fibrosis progression, evaluated by measuring liver stiffness.

Conclusions

The presence of CXCR4-using viruses in patients receiving a potent antiretroviral therapy does not influence HCV RNA concentration or liver fibrosis.

The Role of the NLRP3 Inflammasome in Fibrosis

Fibrosis leads to the deposition of collagens in organs and tissues. The resulting pathology induces a loss of function in the organ it is manifested in and this loss of function modulates the morbidity and mortality in that individual. Indeed, approximately 45% of all deaths in the Western world can be attributed to fibrosis and there are no FDA approved drugs for the treatment of fibrosis. The recent discovery of the inflammasome has led to a plethora of studies investigating this inflammatory signaling pathway in a wide variety of pathogen associated diseases. Many studies have focused on the NLRP3 inflammasome and this inflammasome is activated by a wide variety of cellular alarm signals. Once activated, caspase-1 is cleaved, inducing the secretion of IL-1β and IL-18 that signal to aid in the clearance of invading organisms. However, as the knowledge of the inflammasome has expanded, it was found that it can directly control collagen synthesis, leading to the increased deposition of collagens in the tissues such as the lung, liver, heart, and skin. Mice lacking the inflammasome adaptor protein, ASC, failed to become fibrotic when exposed to bleomycin. Inhibition of caspase-1 activity in fibroblasts from patients with the fibrotic disease systemic sclerosis, decreased collagen synthesis and reduced α-smooth muscle actin expression in myofibroblasts. Taken together, these observations suggest that the inflammasome can drive the fibrotic response and paves the way for novel therapeutics to be identified.

HIV/hepatitis C coinfection natural history and disease progression

PURPOSE OF REVIEW

Up to one-third of HIV-infected patients is infected with hepatitis C virus (HCV). It is now widely accepted that HIV accelerates the course of HCV-related chronic liver disease. The improved survival of HIV patients after successful antiretroviral therapy (ART) has led to a significant decline in HIV-related morbidity, and liver disease caused by HCV infection has emerged as a major threat to the survival of HIV patients. HIV/HCV coinfected patients have a more rapid progression to cirrhosis and its complications than HCV monoinfected patients. Even though the effect of HCV on HIV infection and disease progression is less clear, most advocate early anti-HCV treatment to reduce the risk of chronic liver disease.

RECENT FINDINGS

Recent studies support current recommendations to begin ART early in the course of HIV infection in order to limit progression of liver disease in coinfected patients. HIV coinfection has a negative impact on HCV pathogenesis, and despite increased risk of drug-related hepatotoxicity, successful response to ART might lessen progression of chronic liver disease and improve response to anti-HCV therapy.

SUMMARY

HIV infection affects rate of liver disease progression in those with HCV coinfection. Treatment of HIV may result in slower rates of progression and liver mortality.

Immunopathogenesis of HIV/hepatitis C virus coinfection

As a result of shared infection routes, approximately 25% of individuals infected with HIV in North America are also infected with hepatitis C virus (HCV). In the setting of HIV coinfection, the course of HCV disease is more aggressive, resulting in higher HCV viral loads and a more rapid progression of liver pathology. With the success of HAART, HCV-related end-stage liver disease has become a leading cause of morbidity and mortality in HIV/HCV-coinfected patients. In this article, we will discuss recent studies examining the immune response during HIV and HCV coinfection, focusing on alterations or dysfunctions in virus-specific T-cell responses that may play a role in the immunopathogenesis of HIV/HCV coinfection. Summarizing the impact of HIV coinfection on HCV-specific T-cell immunity and highlighting some of the proposed mechanisms of T-cell dysfunction in HIV/HCV-coinfected individuals may uncover information that could lead to new treatment strategies for these patients experiencing accelerated liver disease and generally poorer outcomes than their HCV-monoinfected counterparts.