Incident Hepatitis C Virus Infections in the Swiss HIV Cohort Study: Changes in Treatment Uptake and Outcomes Between 1991 and 2013

Background.  The hepatitis C virus (HCV) epidemic is evolving rapidly in patients infected with human immunodeficiency virus (HIV). We aimed to describe changes in treatment uptake and outcomes of incident HCV infections before and after 2006, the time-point at which major changes in HCV epidemic became apparent. Methods.  We included all adults with an incident HCV infection before June 2012 in the Swiss HIV Cohort Study, a prospective nationwide representative cohort of individuals infected with HIV. We assessed the following outcomes by time period: the proportion of patients starting an HCV therapy, the proportion of treated patients achieving a sustained virological response (SVR), and the proportion of patients with persistent HCV infection during follow-up. Results.  Of 193 patients with an HCV seroconversion, 106 were diagnosed before and 87 after January 2006. The proportion of men who have sex with men increased from 24% before to 85% after 2006 (P < .001). Hepatitis C virus treatment uptake increased from 33% before 2006 to 77% after 2006 (P < .001). Treatment was started during early infection in 22% of patients before and 91% after 2006 (P < .001). An SVR was achieved in 78% and 29% (P = .01) of patients treated during early and chronic HCV infection. The probability of having a detectable viral load 5 years after diagnosis was 0.67 (95% confidence interval [CI], 0.58-0.77) in the group diagnosed before 2006 and 0.24 (95% CI, 0.16-0.35) in the other group (P < .001). Conclusions.  In recent years, increased uptake and earlier initiation of HCV therapy among patients with incident infections significantly reduced the proportion of patients with replicating HCV.

Dysfunctional HIV-specific CD8+ T cell proliferation is associated with increased caspase-8 activity and mediated by necroptosis

Decreased HIV-specific CD8(+) T cell proliferation is a hallmark of chronic infection, but the mechanisms of decline are unclear. We analyzed gene expression profiles from antigen-stimulated HIV-specific CD8(+) T cells from patients with controlled and uncontrolled infection and identified caspase-8 as a correlate of dysfunctional CD8(+) T cell proliferation. Caspase-8 activity was upregulated in HIV-specific CD8(+) T cells from progressors and correlated positively with disease progression and programmed cell death-1 (PD-1) expression, but negatively with proliferation. In addition, progressor cells displayed a decreased ability to upregulate membrane-associated caspase-8 activity and increased necrotic cell death following antigenic stimulation, implicating the programmed cell death pathway necroptosis. In vitro necroptosis blockade rescued HIV-specific CD8(+) T cell proliferation in progressors, as did silencing of necroptosis mediator RIPK3. Thus, chronic stimulation leading to upregulated caspase-8 activity contributes to dysfunctional HIV-specific CD8(+) T cell proliferation through activation of necroptosis and increased cell death.

Changes in biomarkers of liver disease during successful combination antiretroviral therapy in HIV-HCV-coinfected individuals

BACKGROUND

We investigated changes in biomarkers of liver disease in HIV-HCV-coinfected individuals during successful combination antiretroviral therapy (cART) compared to changes in biomarker levels during untreated HIV infection and to HIV-monoinfected individuals.

METHODS

Non-invasive biomarkers of liver disease (hyaluronic acid [HYA], aspartate aminotransferase-to-platelet ratio index [APRI], Fibrosis-4 [FIB-4] index and cytokeratin-18 [CK-18]) were correlated with liver histology in 49 HIV-HCV-coinfected patients. Changes in biomarkers over time were then assessed longitudinally in HIV-HCV-coinfected patients during successful cART (n=58), during untreated HIV-infection (n=59), and in HIV-monoinfected individuals (n=17). The median follow-up time was 3.4 years on cART. All analyses were conducted before starting HCV treatment.

RESULTS

Non-invasive biomarkers of liver disease correlated significantly with the histological METAVIR stage (P<0.002 for all comparisons). The mean ±sd area under the receiver operating characteristic (AUROC) curve values for advanced fibrosis (≥F3 METAVIR) for HYA, APRI, FIB-4 and CK-18 were 0.86 ±0.05, 0.84 ±0.08, 0.80 ±0.09 and 0.81 ±0.07, respectively. HYA, APRI and CK-18 levels were higher in HIV-HCV-coinfected compared to HIV-monoinfected patients (P<0.01). In the first year on cART, APRI and FIB-4 scores decreased (-35% and -33%, respectively; P=0.1), mainly due to the reversion of HIV-induced thrombocytopaenia, whereas HYA and CK-18 levels remained unchanged. During long-term cART, there were only small changes (<5%) in median biomarker levels. Median biomarker levels changed <3% during untreated HIV-infection. Overall, 3 patients died from end-stage liver disease, and 10 from other causes.

CONCLUSIONS

Biomarkers of liver disease highly correlated with fibrosis in HIV-HCV-coinfected individuals and did not change significantly during successful cART. These findings suggest a slower than expected liver disease progression in many HIV-HCV-coinfected individuals, at least during successful cART.

Simultaneous TCR and CD244 signals induce dynamic downmodulation of CD244 on human antiviral T cells

Various cosignaling molecules on T cells can contribute to activation, inhibition, or exhaustion, depending on context. The surface receptor signaling lymphocytic activation molecule (SLAM) family receptor CD244 (2B4/SLAMf4) has been shown to be capable of either inhibitory or enhancing effects upon engagement of its ligand CD48 (SLAMf2). We examined phenotypes of CD8 T cells from HIV(+) and HIV(neg) human donors, specific for HIV and/or respiratory syncytial virus. Cultured and ex vivo CD8 T cells expressed PD-1, CD244, and TIM-3. We found that ex vivo CD8 T cells downregulated CD244 in response to superantigen. Furthermore, cognate peptide induced rapid downregulation of both CD244 and TIM-3, but not PD-1, on CD8 T cell clones. CD244 downmodulation required simultaneous signaling via both TCR and CD244 itself. Using a pH-sensitive fluorophore conjugated to avidin-Ab tetramers, we found that CD244 crosslinking in the presence of TCR signaling resulted in rapid transport of CD244 to an acidic intracellular compartment. Downregulation was not induced by PMA-ionomycin, or prevented by PI3K inhibition, implicating a TCR-proximal signaling mechanism. CD244 internalization occurred within hours of TCR stimulation and required less peptide than was required to induce IFN-γ production. The degree of CD244 internalization varied among cultured CD8 T cell lines of different specificities, and correlated with the enhancement of IFN-γ production in response to CD48 blockade in HIV(+), but not HIV(neg), subjects. Our results indicate that rapid CD244 internalization is induced by a two-signal mechanism and plays a role in modulation of antiviral CD8 T cell responses by CD48-CD244 signaling.

Dynamic regulation correlates with variable inhibitory function of CD244 on antiviral CD8 T cells (P6117)

Antigen-experienced T cells express a wide variety of costimulatory molecules, some of which can contribute to activating, inhibitory, or exhaustion pathways depending on context. In particular 2B4 (CD244/ SLAMf4) has been shown to be capable of either inhibitory or enhancing effects upon engagement of its ligand CD48 (SLAMf2). We examined the phenotypes of CD8 T cell lines and clones derived from HIV-infected or -uninfected subjects, and specific for HIV or for respiratory syncytial virus. Antiviral CTL expressed varying levels of PD-1, 2B4, and TIM-3. Cognate peptide induced rapid downregulation of both 2B4 and TIM-3, but not PD-1 on cultured CD8 T cells. 2B4 downregulation also occurred directly ex vivo and required simultaneous signaling via both TCR and 2B4, as downregulation was not observed in the absence of antigen or in the presence of CD48-blocking antibody. 2B4 downregulation was not induced by PMA or prevented by PI3-kinase inhibition, implicating a TCR-proximal signaling mechanism. Downregulation occurred rapidly upon stimulation with a low dose of peptide, concomitant with internalization of CD3 and CD8. The degree of 2B4 downregulation varied among CD8 T cells of different specificities and HLA restrictions, and the degree of downregulation correlated with the respective enhancement or suppression of antiviral IFNγ production in response to CD48 blockade. Our results indicate a role for 2B4 downregulation in modulation of antiviral CD8 T cell responses.

Parvovirus 4 infection and clinical outcome in high-risk populations

Parvovirus 4 (PARV4) is a DNA virus frequently associated with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections, but its clinical significance is unknown. We studied the prevalence of PARV4 antibodies in 2 cohorts of HIV- and HCV-infected individuals (n = 469) and the correlations with disease status. We found that PARV4 infection frequently occurred in individuals exposed to bloodborne viruses (95% in HCV-HIV coinfected intravenous drug users [IDUs]). There were no correlations between PARV4 serostatus and HCV outcomes. There was, however, a significant association with early HIV-related symptoms, although because this was tightly linked to both HCV status and clinical group (IDU), the specific role of PARV4 is not yet clear.

The recent breakthroughs in the understanding of host genomics in hepatitis C

BACKGROUND

Hepatitis C Virus (HCV) infection is spontaneously resolved in about 30% of acutely infected individuals. In those who progress to chronic hepatitis C, HCV therapy permanently eradicates infection in about 40% of cases. It has long been suspected that host genetic factors are key determinants for the control of HCV infection.

DESIGN

We will review in this study four genome-wide association studies (GWAS) and two large candidate gene studies that assessed the role of host genetic variation for the natural and treatment-induced control of HCV infection.

RESULTS

The studies consistently identified genetic variation in interleukin 28B (IL28B) as the strongest predictor for the control of HCV infection. Importantly, single nucleotide polymorphisms (SNPs) in IL28B strongly predicted both spontaneous and treatment-induced HCV recovery. IL28B is located on chromosome 19 and encodes interferon-λ, a type III interferon with antiviral activity, which is mediated through the JAK-STAT pathway by inducing interferon-stimulated genes. The SNPs identified in the GWAS are in high linkage disequilibrium with coding or functional non-coding SNPs that might modulate function and/or expression of IL28B. The role of the different IL28B alleles on gene expression and cytokine function has not yet been established.

CONCLUSIONS

These findings provide strong genetic evidence for the influence of interferon-λ for both the natural and treatment-induced control of HCV infection, and support the further investigation of interferon-λ for the treatment of chronic hepatitis C. Furthermore, genetic testing before HCV therapy could provide important information towards an individualized HCV treatment.

Cellular immune responses to HCV core increase and HCV RNA levels decrease during successful antiretroviral therapy

BACKGROUND

Hepatitis C virus (HCV) infection is a major cause of morbidity in HIV infected individuals. Coinfection with HIV is associated with diminished HCV-specific immune responses and higher HCV RNA levels.

AIMS

To investigate whether long-term combination antiretroviral therapy (cART) restores HCV-specific T cell responses and improves the control of HCV replication.

METHODS

T cell responses were evaluated longitudinally in 80 HIV/HCV coinfected individuals by ex vivo interferon-gamma-ELISpot responses to HCV core peptides, that predominantly stimulate CD4(+) T cells. HCV RNA levels were assessed by real-time PCR in 114 individuals.

RESULTS

The proportion of individuals with detectable T cell responses to HCV core peptides was 19% before starting cART, 24% in the first year on cART and increased significantly to 45% and 49% after 33 and 70 months on cART (p=0.001). HCV-specific immune responses increased in individuals with chronic (+31%) and spontaneously cleared HCV infection (+30%). Median HCV RNA levels before starting cART were 6.5 log(10) IU/ml. During long-term cART, median HCV-RNA levels slightly decreased compared to pre-cART levels (-0.3 log10 IU/ml, p=0.02).

CONCLUSIONS

Successful cART is associated with increasing cellular immune responses to HCV core peptides and with a slight long-term decrease in HCV RNA levels. These findings are in line with the favourable clinical effects of cART on the natural history of hepatitis C and with the current recommendation to start cART earlier in HCV/HIV coinfected individuals.

Tracking the transcriptional host response from the acute to the regenerative phase of experimental pneumococcal meningitis

BACKGROUND

Despite the availability of effective antibiotic therapies, pneumococcal meningitis (PM) has a case fatality rate of up to 30% and causes neurological sequelae in up to half of the surviving patients. The underlying brain damage includes apoptosis of neurons in the hippocampus and necrosis in the cortex. Therapeutic options to reduce acute injury and to improve outcome from PM are severely limited.With the aim to develop new therapies a number of pharmacologic interventions have been evaluated. However, the often unpredictable outcome of interventional studies suggests that the current concept of the pathophysiologic events during bacterial meningitis is fragmentary. The aim of this work is to describe the transcriptomic changes underlying the complex mechanisms of the host response to pneumococcal meningitis in a temporal and spatial context using a well characterized infant rat model.

METHODS

Eleven days old nursing Wistar rats were infected by direct intracisternal injection of 2 x 106 cfu/ml of Streptococcus pneumoniae. Animals were sacrificed at 1, 3, 10 and 26 days after infection, the brain harvested and the cortex and hippocampus were sampled. The first two time points represent the acute and sub-acute phase of bacterial meningitis, whereas the latter represent the recovery phase of the disease.

RESULTS

The major events in the regulation of the host response on a transcriptional level occur within the first 3 days after infection. Beyond this time, no differences in global gene expression in infected and control animals were detectable by microarray analysis. Whereas in the acute phase of the disease immunoregulatory processes prevail in the hippocampus and the cortex, we observed a strong activation of neurogenic processes in the hippocampal dentate gyrus, both by gene expression and immunohistology starting as early as 3 days after infection.

CONCLUSIONS

Here we describe the cellular pathways involved in the host response to experimental pneumococcal meningitis in specified disease states and brain regions. With these results we hope to provide the scientific basis for the development of new treatment strategies which take the temporal aspects of the disease into account.

[Asteroid hyalosis within an epiretinal membrane]

CASE REPORT

In May 2007 an 80-year-old man with a known proliferative diabetic retinopathy presented in our outpatient department with a decrease in visual acuity of his right eye. There was a thick asteroid hyalosis preventing fundus examination. Sonographically, there were vitreoretinal tractions requiring a vitrectomy. During surgery an epipapillary membrane was removed.

RESULTS

Microscopically round amorphous bodies were conspicuous which were slightly basophilic in the H&E stain. The amorphous bodies were strongly positive in the periodic acid-Schiff staining. They were embedded in a fibrovascular stroma and partly surrounded by inflammatory cells with numerous giant cells of foreign body reaction.

CONCLUSION

Asteroid hyalosis is a common degenerative disorder in the vitreous body. The aetiology and the pathogenesis of the asteroid bodies are not yet fully understood. An association of asteroid hyalosis with systemic diseases like diabetes mellitus, arterial hypertension, hyperlidpidaemia and atherosclerotic vasculopathy is postulated. Normally, therapy for an asymptomatic asteroid hyalosis is not necessary. The tractive proliferative diabetic retinopathy in our patient did require surgery. The incorporation of hyaloid bodies into an epiretinal membrane with the induction of a foreign body reaction is unusual.

[Herpes keratitis after corneal trauma--a possible occupational disease?]

BACKGROUND

Herpes simplex virus (HSV) keratitis is among the most common causes of infectious corneal disease and encompasses epithelial, stromal and endothelial disease processes. Different trigger factors are commonly thought to be associated with recurrences of HSV keratitis but, in spite of its high prevalence, the exact mechanisms for the recurring nature of HSV keratitis are unclear. Ophthalmologists therefore face difficulties when asked to assess the relation between ocular trauma and subsequent herpetic eye disease.

CASE REPORT

At the age of 21, a man developed stromal herpetic keratitis of his right eye. Ten years later, he experienced a superficial corneal injury of the same eye with a metal foreign body during work. Subsequently, severe stromal keratitis with multiple recurrences developed. Due to progressive endothelial decompensation, a perforating keratoplasty was performed at the age of 51. Six years thereafter, re-keratoplasty became necessary because of a fungal keratitis of the transplant. The patient was convinced that the initial occupational corneal injury was the cause of the following recurrences of HSV keratitis and therefore was responsible for the resulting reduction of visual acuity. He thus filed an action for receiving an invalidity pension.

RESULTS

The different possible pathophysiological situations at the time of induction of a traumatic herpetic keratitis are presented and discussed. General guidelines for the assessment of traumatic herpetic keratitis are suggested.

CONCLUSIONS

Patients who have suffered from one or more previous episodes of HSV keratitis are at a high risk for recurrences. In the depicted case, stromal keratitis had already occurred once before the trauma. The recurrences of herpetic keratitis following the injury therefore could not be attributed to the trauma with sufficient probability.

Effect of dacarbazine (DTIC) on cultures from malignant melanoma of the choroid: an immunohistochemical and electron microscopic study

INTRODUCTION

Dacarbazine (DTIC) is a very effective chemotherapeutic agent used in the treatment of cutaneous melanoma; it also could have a potential therapeutic value as an antimetastatic agent in the treatment of choroidal melanoma.

OBJECTIVE

To study the HMB-45 and S100 protein expression in choroidal melanoma cultures with and without DTIC, and compare the immunohistochemical and electron microscopic changes in both groups.

METHODS

Five- and seven-day cultures of choroidal melanoma (n = 21) were cultivated in diffusion chambers. The cultures were divided in two groups: I group (control group)--the cells were grown in 199-medium; II group--the cells were in 199-medium supplemented with 0.03 mg/ml of DTIC. Immunohistochemical studies were performed with paraffin-embedded material of the cultures by the avidin-biotin-alkaline phosphatase technique. Araldit-embedded material was studied by electron microscopy.

RESULTS

The expression of HMB-45 and S100 protein in the cultures with DTIC ranged from slightly positive to negative. The tumor cells were severely damaged. Electron microscopy in this group showed presence only of cellular fragments. In the DTIC-free group the HMB-45 and S100 expressions were strongly positive. There were no electron microscopic evidence of cellular death.

CONCLUSION

DTIC suppresses the growth of choroidal melanoma in vitro. These results indicate that further studies are warranted to elucidate the effect of DTIC in vivo.