Hepatitis delta infection among persons living with HIV in Europe.

BACKGROUND AND AIMS: A high prevalence of hepatitis delta virus (HDV) infection, the most severe form of viral hepatitis, has been reported among persons living with HIV (PLWH) in Europe. We analysed data from a large HIV cohort collaboration to characterize HDV epidemiological trends across Europe, as well as its impact on clinical outcomes. METHODS: All PLWH with a positive hepatitis B surface antigen (HBsAg) in the Swiss HIV Cohort Study and EuroSIDA between 1988 and 2019 were tested for anti-HDV antibodies and, if positive, for HDV RNA. Demographic and clinical characteristics at initiation of antiretroviral therapy were compared between HDV-positive and HDV-negative individuals using descriptive statistics. The associations between HDV infection and overall mortality, liver-related mortality as well as hepatocellular carcinoma (HCC) were assessed using cumulative incidence plots and cause-specific multivariable Cox regression. RESULTS: Of 2793 HBsAg-positive participants, 1556 (56%) had stored serum available and were included. The prevalence of HDV coinfection was 15.2% (237/1556, 95% confidence interval [CI]: 13.5%-17.1%) and 66% (132/200) of HDV-positive individuals had active HDV replication. Among persons who inject drugs (PWID), the prevalence of HDV coinfection was 50.5% (182/360, 95% CI: 45.3%-55.7%), with similar estimates across Europe, compared to 4.7% (52/1109, 95% CI: 3.5%-5.9%) among other participants. During a median follow-up of 10.8 years (interquartile range 5.6-17.8), 82 (34.6%) HDV-positive and 265 (20.1%) HDV-negative individuals died. 41.5% (34/82) of deaths were liver-related in HDV-positive individuals compared to 17.7% (47/265) in HDV-negative individuals. HDV infection was associated with overall mortality (adjusted hazard ratio 1.6; 95% CI 1.2-2.1), liver-related death (2.9, 1.6-5.0) and HCC (6.3, 2.5-16.0). CONCLUSION: We found a very high prevalence of hepatitis delta among PWID across Europe. Among PLWH who do not inject drugs, the prevalence was similar to that reported from populations without HIV. HDV coinfection was associated with liver-related mortality and HCC incidence.

Long-Term Study of Hepatitis Delta Virus Infection at Secondary Care Centers: The Impact of Viremia on Liver-Related Outcomes.

BACKGROUND AND AIMS: Hepatitis delta virus (HDV) infection is associated with fast progression to liver cirrhosis and liver complications. Previous studies have, however, been mainly from tertiary care centers, with risk for referral bias toward patients with worse outcomes. Furthermore, the impact of HDV viremia per se on liver-related outcomes is not really known outside the human immunodeficiency virus co-infection setting. We have therefore evaluated the long-term impact of HDV viremia on liver-related outcomes in a nationwide cohort of patients with hepatitis B and D co-infection, cared for at secondary care centers in Sweden. APPROACH AND RESULTS: In total, 337 patients with anti-HDV positivity, including 233 patients with HDV RNA viremia and 91 without HDV viremia at baseline, were retrospectively studied, with a mean follow-up of 6.5 years (range, 0.5-33.1). The long-term risks for liver-related events (i.e., hepatocellular carcinoma [HCC], hepatic decompensation, or liver-related death/transplantation) were assessed, using Cox regression analysis. The risk for liver-related events and HCC was 3.8-fold and 2.6-fold higher, respectively, in patients with HDV viremia compared with those without viremia, although the latter was not statistically significant. Among patients with HDV viremia with no baseline cirrhosis, the cumulative risk of being free of liver cirrhosis or liver-related events was 81.9% and 64.0% after 5 and 10 years of follow-up, respectively. This corresponds to an incidence rate of 0.04 cases per person-year. CONCLUSIONS: HDV RNA viremia is associated with a 3.8-fold higher risk for liver-related outcomes. The prognosis was rather poor for patients with HDV viremia without cirrhosis at baseline, but it was nevertheless more benign than previous estimates from tertiary centers. Our findings may be of importance when making decisions about treatment and evaluating potential outcomes of upcoming antivirals against HDV.

Clinical Outcomes in Persons Coinfected With Human Immunodeficiency Virus and Hepatitis C Virus: Impact of Hepatitis C Virus Treatment.

BACKGROUND: A hepatitis C (HCV) cure is associated with changes in lipids and inflammatory biomarkers, but its impact on clinical endpoints among treated human immunodeficiency virus (HIV)/HCV coinfected persons is unclear. METHODS: People living with HIV from EuroSIDA with a known HCV status after January 2001 were classified into strata based on time-updated HCV RNA measurements and HCV treatment, as either HCV antibody-negative; spontaneously resolved HCV; chronic, untreated HCV; cured HCV (HCV RNA-negative); or HCV treatment failures (HCV RNA-positive). Poisson regression was used to compare incidence rates between HCV groups for end-stage liver disease (ESLD; including hepatocellular carcinoma [HCC]), non-acquired immunodeficiency virus defining malignancy (NADM; excluding HCC), and cardiovascular disease (CVD). RESULTS: There were 16 618 persons included (median follow-up 8.3 years, interquartile range 3.1-13.7). There were 887 CVD, 902 NADM, and 436 ESLD events; crude incidence rates/1000 person-years follow-up were 6.4 (95% confidence interval [CI] 6.0-6.9) for CVD, 6.5 (95% CI 6.1-6.9) for NADM, and 3.1 (95% CI 2.8-3.4) for ESLD. After adjustment, there were no differences in incidence rates of NADM or CVD across the 5 groups. HCV-negative individuals (adjusted incidence rate ratio [aIRR] 0.22, 95% CI 0.14-0.34) and those with spontaneous clearance (aIRR 0.61, 95% CI 0.36-1.02) had reduced rates of ESLD compared to cured individuals. Persons with chronic, untreated HCV infections (aIRR 1.47, 95% CI 1.02-2.13) or treatment failure (aIRR 1.80, 95% CI 1.22-2.66) had significantly raised rates of ESLD, compared to those who were cured. CONCLUSIONS: Incidences of NADM or CVD were independent of HCV group, whereas those cured had substantially lower incidences of ESLD, underlining the importance of successful HCV treatment for reducing ESLD.

IL13Rα2 expression identifies tissue-resident IL-22-producing PLZF+ innate T cells in the human liver.

Innate lymphocytes are selectively enriched in the liver where they have important roles in liver immunology. Murine studies have shown that type I NKT cells can promote liver inflammation, whereas type II NKT cells have an anti-inflammatory role. In humans, type II NKT cells were found to accumulate in the gut during inflammation and IL13Rα2 was proposed as a marker for these cells. In the human liver, less is known about type I and II NKT cells. Here, we studied the phenotype and function of human liver T cells expressing IL13Rα2. We found that IL13Rα2 was expressed by around 1% of liver-resident memory T cells but not on circulating T cells. In support of their innate-like T-cell character, the IL13Rα2+ T cells had higher expression of promyelocytic leukaemia zinc finger (PLZF) compared to IL13Rα2- T cells and possessed the capacity to produce IL-22. However, only a minority of human liver sulfatide-reactive type II NKT cells expressed IL13Rα2. Collectively, these findings suggest that IL13Rα2 identifies tissue-resident intrahepatic T cells with innate characteristics and the capacity to produce IL-22.

The future disease burden of hepatitis C virus infection in Sweden and the impact of different treatment strategies.

UNLABELLED: OBJECTIVE. Recently, new highly effective direct-acting antivirals (DAAs) against hepatitis C virus (HCV) were introduced. Whether these will alleviate the anticipated increase of liver disease burden in Sweden is unknown, partly because high costs may restrict the use. The objectives were to model the HCV epidemic in Sweden, the burden of disease, and the potential impact of different treatment strategies. MATERIAL AND METHODS: HCV disease progression was modeled to 2030. Scenarios were simulated using new DAAs with sustained annual treatment rate (n = 1130), reduced treatment rate (n = 380) to maintain budget, and increased treatment rates (n = 1430 or 2260) to reduce HCV infections. RESULTS: With today's triple therapies, the estimated number of serious liver complications and death are expected to peak in 2021. Using new DAAs among F0-F4 patients, an unchanged annual treatment rate can reduce the number of HCV infections by 10% by 2030; however, hepatocellular carcinoma (HCC) and mortality will remain unchanged. By reducing to 380 treatments annually and focusing on patients with advanced fibrosis (F3-F4), serious complications will remain constant but the total number of HCV infections will increase. By doubling the number of DAA treatments, HCC-incidence and liver-related deaths would decrease by 65-70% by 2030. CONCLUSION: Mortality and HCC can be reduced with new DAAs and sustained treatment uptake when restricted to F2-F4 patients, or with increased uptake in F0-F4 patients. Treatment restrictions to limit cost may reduce the positive effects and increase the burden of HCV infection. These results may be important for the future strategies of HCV management.

Chronic immune activation in the T cell compartment of HCV/HIV-1 co-infected patients.

Activation of innate and adaptive immune mechanisms in response to infection is necessary to control and clear infections. However, chronic immune activation in human immunodeficiency virus 1 (HIV-1) infection has a series of detrimental effects and is a major driving force in HIV-1 disease progression. We recently found that patients with chronic hepatitis C virus (HCV)/HIV-1 co-infection display sharply elevated immune activation as determined by expression of CD38 in T cells. High immune activation was observed despite that these patients were on effective antiretroviral therapy (ART), which usually brings down activation levels in HIV-infected people. HCV treatment with pegylated interferon-α (IFNα) and ribavirin reduced activation, and this was at first glance unexpected as IFNα is believed to be involved in driving activation. Here, we briefly summarize these findings and discuss them in context of the emerging roles of the gut barrier and the liver in chronic immune activation and viral disease progression.

Expansion of functionally skewed CD56-negative NK cells in chronic hepatitis C virus infection: correlation with outcome of pegylated IFN-alpha and ribavirin treatment.

NK cells are important innate immune effector cells, normally characterized as CD56(+)CD3(-) lymphocytes. In this study, we report that CD56(-)CD16(+) NK cells expand in many patients with chronic hepatitis C virus infection. These CD56(-) NK cells were functionally impaired with respect to cytokine production upon target cell recognition, in comparison to CD56(dim) and CD56(bright) NK cell subsets. In particular, CD56(-) NK cells were strikingly defective in their polyfunctional response as measured by the coexpression of MIP-1beta, IFN-gamma, TNF-alpha, and CD107a degranulation. The ability of these cells to mediate three or four of these functions was poor; expression of MIP-1beta alone dominated their response. CD56(-) NK cells retained expression of receptors such as the natural cytotoxicity receptors and NKG2D, whereas the expression of CD57 and perforin was lower when compared with CD56(dim) NK cells. Interestingly, pretreatment levels of CD56(-) NK cells correlated with the outcome of pegylated IFN-alpha and ribavirin treatment. In patients with CD56(-) NK cells in the range of healthy subjects, 80% reached a sustained virological response to treatment, whereas only 25% of patients with levels clearly above those in healthy subjects experienced a sustained virological response. Thus, chronic hepatitis C virus infection is associated with an expansion of CD56(-) NK cells functionally skewed toward MIP-1beta production only. Furthermore, high levels of these cells reveal a disturbance in innate cellular immunity that is associated with an impaired ability to respond to antiviral treatment with IFN-alpha and ribavirin.

High levels of chronic immune activation in the T-cell compartments of patients coinfected with hepatitis C virus and human immunodeficiency virus type 1 and on highly active antiretroviral therapy are reverted by alpha interferon and ribavirin treatment.

Chronic immune activation is a driver of human immunodeficiency virus type 1 (HIV-1) disease progression. Here, we describe that subjects with chronic hepatitis C virus (HCV)/HIV-1 coinfection display sharply elevated immune activation as determined by CD38 expression in T cells. This occurs, despite effective antiretroviral therapy, in both CD8 and CD4 T cells and is more pronounced than in the appropriate monoinfected control groups. Interestingly, the suppression of HCV by pegylated alpha interferon and ribavirin treatment reduces activation. High HCV loads and elevated levels of chronic immune activation may contribute to the high rates of viral disease progression observed in HCV/HIV-1-coinfected patients.

Elevated numbers of Fc gamma RIIIA+ (CD16+) effector CD8 T cells with NK cell-like function in chronic hepatitis C virus infection.

CTL are crucial in the defense against viral infections. In the course of investigating peripheral blood and intrahepatic CD8 T cells in patients with chronic hepatitis C virus (HCV) infection, we observed a significant population of CD8 T cells expressing the FcgammaRIIIA (CD16) receptor. This observation led us to characterize these cells with respect to their phenotype and function in a cohort of patients with chronic HCV infection as well as in healthy blood donors. On average, 10% of peripheral blood CD8 T cells from HCV-infected patients expressed CD16 compared with only a few percent in healthy donors. CD16(+) CD8 T cells displayed a late-stage effector phenotype with high levels of perforin. These cells exhibited a restricted TCR profile suggesting underlying clonal expansion. Stimulation of CD16 on CD8 T cells evoked a vigorous response similar to that of CD16 stimulation in NK cells. Our data suggest that CD8 T cells, during chronic HCV infection in humans, continue to differentiate beyond defined stages of terminal effector cells, acquiring CD16 and NK cell-like functional properties.