Viral factors associated with cytokine expression during HCV/HIV co-infection

Hepatitis C virus infection and pain sensitivity in patients on methadone or buprenorphine maintenance therapy for opioid use disorders

BACKGROUND

Patients with opioid use disorders on opioid agonist therapy (OAT) have lower pain tolerance compared to controls. While chronic viral infections such as HCV and HIV have been associated with chronic pain in this population, no studies have examined their impact on pain sensitivity.

METHODS

We recruited 106 adults (41 uninfected controls; 40 HCV mono-infected; and 25 HCV/HIV co-infected) on buprenorphine or methadone to assess whether HCV infection (with or without HIV) was associated with increased experimental pain sensitivity and self-reported pain. The primary outcome was cold pain tolerance assessed by cold-pressor test. Secondary outcomes were cold pain thresholds, wind-up ratios to repetitive mechanical stimulation (i.e., temporal summation) and acute and chronic pain. Multivariable regression models evaluated associations between viral infection status and outcomes, adjusting for other factors.

RESULTS

No significant differences were detected across groups for primary or secondary outcomes. Adjusted mean cold pain tolerance was 25.7 (uninfected controls) vs. 26.8 (HCV mono-infection) vs. 25.3 (HCV/HIV co-infection) seconds (global p-value=0.93). Current pain appeared more prevalent among HCV mono-infected (93%) compared to HCV/HIV co-infected participants (76%) and uninfected controls (80%), as did chronic pain (77% vs. 64% vs. 61%, respectively). However, differences were not statistically significant in multivariable models.

CONCLUSION

This study did not detect an association between HCV infection and increased sensitivity to pain among adults with and without HIV who were treated with buprenorphine or methadone for opioid use disorders. Results reinforce that pain and hyperalgesia are common problems in this population.

Human immunodeficiency virus, hepatitis C, and inflammatory biomarkers in individuals with alcohol problems: a cross-sectional study

Background

Assessing whether hepatitis C (HCV) co-infection with human immunodeficiency virus (HIV) is associated with increased inflammation is complex. The liver, integral to inflammatory biomarker synthesis, is compromised by HCV and alcohol abuse. Using single liver-synthesized biomarkers (e.g. C-reactive protein) to represent inflammation may not be appropriate in HIV/HCV co-infection. We hypothesized that 1) detectable HIV/HCV RNA was independently associated with increased inflammation; 2) a composite inflammation measure describes inflammation differently from single inflammatory biomarkers.

Methods

We compared inflammation by HIV/HCV group in a cohort of 361 HIV infected participants from the HIV-Longitudinal Interrelationships of Viruses and Ethanol study. Inflammatory biomarkers >75th percentile were considered elevated. Associations between HIV/HCV group and elevated biomarkers were analyzed as a composite measure (inflammatory burden) or individually. We defined inflammatory burden as number of concurrently elevated biomarkers. Biomarkers included interleukin-6 (IL-6), C-reactive protein (CRP), cystatin C, serum amyloid-A (SAA), tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10). Covariates: alcohol, liver fibrosis, comorbidities, CD4 count, antiretroviral therapy, substance use.

Results

Detectable HIV and HCV RNA (OR = 2.49; 95% CI = 1.05–5.89) and detectable HCV RNA alone (2.95; 1.08–8.01) were independently associated with increased odds of having a greater inflammatory burden compared to undetectable viremia. Elevated IL-10 (7.79; 1.90–31.97) and TNF-α (7.70; 1.42–41.83) were independently associated with detectable HIV and HCV RNA. Elevated IL-10 was also associated with detectable HCV RNA alone (5.51; 1.17, 25.84).

Conclusions

Detectable HIV and HCV replication versus undetectable replication was associated with inflammatory burden and certain inflammatory biomarkers independently of alcohol consumption, liver fibrosis and other comorbidities.

Interleukin-6 is associated with noninvasive markers of liver fibrosis in HIV-infected patients with alcohol problems

Both HIV and hepatitis C virus (HCV) cause chronic inflammation and alterations in serum inflammatory cytokines. The impact of inflammatory cytokines on liver fibrosis is not well understood. We studied the association between interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α and liver fibrosis in HIV-infected patients with current or past alcohol problems (CAGE ≥2 or physician investigator diagnosis). Liver fibrosis was estimated with FIB-4 (FIB-4 <1.45 defined the absence of liver fibrosis and FIB-4 >3.25 defined advanced fibrosis). Logistic regression was used to assess the association between cytokines and fibrosis, adjusting for age, sex, CD4, HIV RNA, current antiretroviral therapy, body mass index, and HCV. Secondary analyses explored whether the association between HCV and liver fibrosis was mediated by these cytokines. Participants (n=308) were all HIV-infected; 73% were male with a mean age of 42 years; half had detectable HCV-RNA, 60.7% had an absence of liver fibrosis, and 10.1% had advanced fibrosis. In models that adjusted for each cytokine separately, higher levels of IL-6 were significantly associated with an absence of fibrosis [adjusted OR (95% CI): 0.43 (0.19, 0.98), p=0.05] and were borderline significant for advanced fibrosis [adjusted OR (95% CI): 8.16 (0.96, 69.54), p=0.055]. In the final model, only higher levels of IL-6 remained significantly associated with advanced liver fibrosis [adjusted OR (95% CI): 11.78 (1.17, 118.19), p=0.036]. Adjustment for inflammatory cytokines attenuated the adjusted OR for the association between HCV and fibrosis in the case of IL-6 [for the absence of fibrosis from 0.32 (0.17, 0.57) p<0.01 to 0.47 (0.23, 0.96) p=0.04; and for advanced fibrosis from 7.22 (2.01, 25.96) p<0.01 to 6.62 (1.20, 36.62) p=0.03], suggesting IL-6 may be a partial mediator of the association between HCV and liver fibrosis. IL-6 was strongly and significantly associated with liver fibrosis in a cohort of HIV-infected patients with alcohol problems. IL-6 may be a useful predictive marker for liver fibrosis for HIV-infected patients.

Human immunodeficiency virus enhances hepatitis C virus replication by differential regulation of IFN and TGF family genes

HIV co-infection significantly impacts the natural history of hepatitis C virus (HCV) by increasing plasma HCV viral load, accelerating liver disease progression, and reducing rates of HCV clearance. Cytokines play an important role in regulating hepatic inflammation and fibrogenesis during chronic HCV infection, yet the impact of HIV on cytokine expression is unknown. In this study, an HCV continuous infection cell culture system was modified to permit co-infection with HIV to test the hypothesis that virus-induced disregulation of immune-response genes, particularly interferons and TGF-β, may create a permissive environment for the initial establishment of HIV/HCV co-infection in the host. CCR5-expressing Huh-7.5 hepatoma cells were transduced with human CD4 antigen to allow HIV infection in vitro. Co-infection of CD4⁺ Huh-7.5 cells with HIV and HCV or co-culture of HIV-infected CD4⁺ Huh-7.5 cells and HCV-infected Huh-7.5 cells increased the level of HCV RNA compared to HCV mono-infection. Quantitative gene expression analysis revealed HIV-induced up regulation of most tested IFN family genes when compared to HCV or co-infection. HCV infection induced up regulation of many TGF family genes that were subsequently down-regulated in the presence of HIV or HIV/HCV. Interestingly, co-infection resulted in down regulation of several IFN genes and significant up regulation of TGF-β genes leading to an overall enhancement of HCV replication. These data suggest that HIV infection may influence HCV replication in vitro by increasing levels of HCV RNA, possibly through the differential regulation of endogenous IFN and TGF family genes.

Antiviral treatment for chronic hepatitis C in patients with human immunodeficiency virus

BACKGROUND

Antiviral treatment for chronic hepatitis C may be less effective if patients are co-infected with human immunodeficiency virus (HIV).

OBJECTIVES

To assess the benefits and harms of antiviral treatment for chronic hepatitis C in patients with HIV.

SEARCH STRATEGY

Trials were identified through manual and electronic searches in The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded. The last search was May 2009.

SELECTION CRITERIA

Randomised trials comparing at least 12 weeks of any anti-HCV treatment versus another treatment regimen or no treatment. Included patients had chronic hepatitis C and stable HIV irrespective of previous antiviral therapy.

DATA COLLECTION AND ANALYSIS

Data extraction and assessment of risk of bias were done in duplicate. Analysis was by intention-to-treat.

MAIN RESULTS

Fourteen trials were included. None of the included 2269 patients were previously treated for chronic hepatitis C. Peginterferon (either 2a, 180 microgram, or 2b, 1.5 microgram/kg, once weekly) plus ribavirin was more effective in achieving end of treatment and sustained virological response compared with interferon plus ribavirin (5 trials, 1340 patients) or peginterferon (2 trials, 714 patients). The benefit of peginterferon plus ribavirin was seen irrespective of HCV genotype although patients with genotype 1 or 4 had lower response rates (27%) than patients with genotype 2 or 3 (56%). The remaining trials compared different treatment regimens in patients who were treatment naive or had no virological response after three months of treatment, but overall they had not enough power to show any effect of increasing the dose of interferon or adding both amantadine or ribavirin. The overall mortality was 23/2111 patients with no significant differences between treatment regimens. Treatment increased the risk of adverse events including anaemia and flu-like symptoms, and several serious adverse events occurred including fatal lactic acidosis, liver failure, and suicide due to depression.

AUTHORS' CONCLUSIONS

Peginterferon plus ribavirin may be considered a treatment for patients with chronic hepatitis C and stable HIV who have not received treatment for hepatitis C as the intervention may clear the blood of HCV RNA. Supporting evidence comes mainly from the analysis of this non-validated surrogate outcome assessed in comparisons against other antiviral treatments. There is no evidence on treatment of patients who have relapsed or did not respond to previous therapy. Careful monitoring of adverse events is warranted.

Can serum TGF-beta 1 be used to evaluate the response to antiviral therapy of haemophilic patients with HCV-related chronic hepatitis?

Congenital coagulation disorders limit the use of liver biopsy, especially when repeated assessment is needed. TGF-beta 1 plays a pivotal role in inducing fibrosis and has been proposed as its surrogate marker. Aiming at validating the clinical utility of this cytokine, fifteen haemophilic patients suffering from HCV-related chronic hepatitis were treated with Peg-IFN alpha2beta plus Ribavirin. Serum TGFbeta 1, viral load and liver enzymes were analyzed at baseline and at six, twelve, and eighteen months. As expected, patients initially showed significantly higher TGF-beta 1 levels than age-matched controls (43.8 ng/mL, 28.7-46.4 vs. 26.9 ng/mL, 23.0-34.0, median and 95% CI; p=0.004). The end of therapy response rate was 67%. The main finding was a significant drop in TGF-beta 1 at six months compared to baseline values; this drop de facto predicted the levels reached in the following six months, which were fixed at lower concentrations (37.0 ng/mL, 21.9-43.8 and 27.0 ng/mL, 24.1-44.0 respectively; p<0.009), independently of treatment outcome (three patients were breakthrough, twelve were sustained virological responders (SVRs). During the treatment period none had clinical or biochemical signs of inflammation in other areas. Treatment was followed by a six-month follow-up, at the end of which TGF-beta 1 was increased compared to the previous values, reaching the initial levels in ten SVRs (45 ng/mL, 24.5-52.9). Interestingly, at a longer follow-up, two out of ten SVRs, who displayed the highest values of TGF-beta 1, relapsed. Serum TGF-beta 1 could be used to assess therapeutic outcome and short-term prognosis of HCV-related chronic hepatitis.

Association of hepatitis C virus seropositivity with inflammatory markers and heart failure in persons with coronary heart disease: data from the Heart and Soul study

BACKGROUND

How hepatitis C virus (HCV) affects coronary heart disease (CHD) risk factors and outcomes is largely unknown.

METHODS AND RESULTS

Among a cohort of patients with stable CHD, we examined the association between HCV seropositivity and levels of inflammatory markers (C-reactive protein [CRP], fibrinogen, interleukin-6, and tumor necrosis factor [TNF]-alpha) and risk for the following outcomes: death, cardiovascular (CV) events, and heart failure events. A total of 84 (8.6%) participants were found to be seropositive for HCV. HCV-seropositive patients were found to have significantly lower adjusted mean levels of CRP (2.6 vs. 4.4; P < .01) and fibrinogen (340 vs. 398; P < .01), but higher levels of TNF-alpha (7.1 vs. 4.8; P < .01). Age-adjusted rates for HCV seropositive vs. seronegative were as follows: death 93 vs. 42/1,000p-y (P < .01), CV events 62 vs. 40 (P=.13), and heart failure 76 vs. 29 (P < .01). After adjustment for demographic and clinical factors, HCV remained significantly associated with an increased risk for heart failure events (HR=2.13; 95% CI: 1.19-3.80).

CONCLUSIONS

In this cohort with CHD, HCV seropositive participants had higher rates of death, CV events, and heart failure hospitalizations during follow-up. After adjustment for CV risk factors, HCV seropositivity remained independently associated with risk for heart failure events.

The challenge of hepatitis C in the HIV-infected person

Hepatitis C virus (HCV) coinfection occurs in an estimated one quarter of HIV-infected persons in Europe, Australia, and the United States. As use of highly active antiretroviral drugs has markedly reduced opportunistic infections, HCV-related liver disease has emerged as a leading cause of death. HIV infection adversely affects both the natural history and the treatment of hepatitis C. Because there are no experimental models of coinfection and because the pathogenesis of each infection is incompletely understood, how HIV infection alters hepatitis C is not clear. This review considers the epidemiology, natural history, treatment, and pathogenesis of hepatitis C in HIV-infected persons.