Early Permissiveness of Central Nervous System Cells to Measles Virus Infection Is Determined by Hyperfusogenicity and Interferon Pressure

The cessation of measles virus (MeV) vaccination in more than 40 countries as a consequence of the COVID-19 pandemic is expected to significantly increase deaths due to measles. MeV can infect the central nervous system (CNS) and lead to lethal encephalitis. Substantial part of virus sequences recovered from patients' brain were mutated in the matrix and/or the fusion protein (F). Mutations of the heptad repeat domain located in the C terminal (HRC) part of the F protein were often observed and were associated to hyperfusogenicity. These mutations promote brain invasion as a hallmark of neuroadaptation. Wild-type F allows entry into the brain, followed by limited spreading compared with the massive invasion observed for hyperfusogenic MeV. Taking advantage of our ex vivo models of hamster organotypic brain cultures, we investigated how the hyperfusogenic mutations in the F HRC domain modulate virus distribution in CNS cells. In this study, we also identified the dependence of neural cells susceptibility on both their activation state and destabilization of the virus F protein. Type I interferon (IFN-I) impaired mainly astrocytes and microglial cells permissiveness contrarily to neurons, opening a new way of consideration on the development of treatments against viral encephalitis.

Rapid and persistent decline in soluble CD163 with successful direct-acting antiviral therapy and associations with chronic hepatitis C histology

BACKGROUND AND AIM

Soluble CD 163 (sCD163) is released from activated liver macrophages in chronic viral hepatitis C (HCV) and serum levels reflect liver disease severity. The impact of direct-acting antiviral (DAA)-therapy on sCD163-levels and the ability of sCD163 to predict the presence of liver fibrosis remain unclear. In a combined observational and prospective study, we aimed to investigate changes in sCD163 with DAA-treatment, to investigate associations between sCD163 and histopathological activity and fibrosis and to validate the sCD163-based fibrosis score in HCV-patients.

METHODS

We examined three groups of patients: an Australian (n = 28) treated with pegylated-interferon and a first-generation DAA, a Danish (n = 38) treated with sofosbuvir-based DAA-regimens and a Japanese (n = 562) assessed for activity and fibrosis (Metavir scoring system) in liver biopsies. Serum sCD163-levels were quantified by ELISA.

RESULTS

Thirteen (46%) of the Australian patients achieved sustained virological response (SVR) and only these patients had significant decreases in sCD163-levels (2.7 (95%CI:1.9-3.6) vs. 4.1(2.9-5.7) mg L ^- 1, p = .008). In the Danish group, 37 (97%) patients achieved SVR at 12-weeks post-treatment with 32% reduction in sCD163-levels (5.0 (4.3-5.8) vs. 7.4 (6.3-8.7), p < .001). The decline was rapid and persisted 12 months after treatment cessation (p < .007). sCD163 levels increased in parallel with inflammatory activity and fibrosis (p < .001). The sCD163-based fibrosis score outperformed established fibrosis scores for significant fibrosis (areas under the receiver operating characteristics curves (AUROCs): 0.79 (0.75-0.83) vs. aspartate aminotransferase to platelet ratio index (APRI) 0.73 (0.69-0.77), Fibrosis-4 (FIB-4) 0.74 (0.70-0.78), p < .001).

CONCLUSION

sCD163-levels decline rapidly with successful DAA therapy and are associated with histological inflammatory activity and fibrosis, confirming a key role for macrophages in HCV inflammation and fibrosis and supporting sCD163 as a biomarker of treatment response.

High incidence of the hepatitis C virus recombinant 2k/1b in Georgia: Recommendations for testing and treatment

AIM

The first hepatitis C virus (HCV) recombinant, RF2k/1b, was initially described from Russia and has since then been identified from patients in Ireland, Estonia, Uzbekistan and Cyprus. Many of these patients originated from Georgia; however, there is no information on its prevalence in Georgia or its susceptibility to antiviral treatment.

METHODS

We retrospectively sequenced the non-structural region 5B (NS5B) of the HCV genome in samples from 72 Georgian patients, 36 of whom had been treated with pegylated interferon and ribavirin.

RESULTS

The HCV genotype was determined using the Versant HCV Genotype v2 kit. Based on this typing, 32 patients (44.4%) were infected with genotype 1, 21 (29.1%) genotype 2 and 19 (26.3%) genotype 3. Partial NS5B of these strains was sequenced and analyzed for type, with concordant genotype results for all type 1 and 3 strains. Discrepant results were observed for genotyped 2 strains, with 16 (76%) having NS5B of subtype 1b. On phylogenetic analysis, 15 NS5B sequences of these strains were found in a clade formed by recombinant RF2k/1b strains. The remaining discordant sequence was found within a clade formed by 1b strains.

CONCLUSION

Our findings show that the RF2k/1b recombinant strain is common among Georgian patients previously assumed to be infected with genotype 2. Because genotyping is mainly performed to decide treatment strategies, there is a need to determine the genotype by analysis of at least two genomic regions in strains from Georgian patients considered infected with genotype 2 based on standard HCV genotyping methods.

IL28B favorable genotype and ultrarapid viral response as the earliest treatment predictors of a sustained viral response in a Georgian cohort infected with the hepatitis C genotype 1

OBJECTIVES

The early identification of factors contributing to the successful treatment of hepatitis C infection is important for researchers and clinicians. Studies carried out on the role of an ultrarapid viral response (URVR) for the prediction of a sustained viral response (SVR) have shown its high positive predictive value (PPV). However, data on the combined effect of URVR with IL28B genotypes for the prediction of SVR are lacking. Our aim was to study the role of URVR and IL28B genotypes in the prediction of SVR among patients in Georgia infected with genotype 1.

METHODS

Of a total of 156 patients enrolled in the study, 143 were included in the final analyses. Viral load testing for monitoring the viral response was carried out at 3, 24, 48, and 72 h and at 1, 2, and 4 weeks after the initiation of treatment. IL28B single nucleotide polymorphisms in rs12979860 were genotyped using real-time PCR methods.

RESULTS

Our study showed that URVR was the earliest treatment predictor among genotype 1 patients harboring the IL28B C/C genotype (PPV-100%). Moreover, the C/C genotype was found to have a high PPV among genotype 1 patients without URVR or a rapid viral response, unlike patients infected with genotype 2 or 3. URVR and IL28B C/C genotypes were not as predictive of an SVR among genotype 2 and 3 patients; however, rapid viral responses were highly predictive of an SVR in these patients.

CONCLUSION

Our results suggest that testing for IL28B genotypes and viral load at weeks 1 and 2 may improve the ability to predict an SVR among hepatitis C virus genotype 1 patients; this information may be useful to ensure patient compliance with treatment.

Evolution of hepatic steatosis in patients with advanced hepatitis C: results from the hepatitis C antiviral long-term treatment against cirrhosis (HALT-C) trial

Hepatic steatosis is a common histologic feature in patients with chronic hepatitis C (CHC) but there are no large longitudinal studies describing the progression of steatosis in CHC. We examined changes in steatosis on serial biopsies among CHC patients participating in the Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial. All 1050 patients in the trial had advanced fibrosis at baseline biopsy and were documented not to have had a sustained virological response to peginterferon and ribavirin. Most (94%) patients had genotype 1 infection. At least one protocol follow-up biopsy was read on 892 patients, and 699 had the last biopsy performed 3.5 years after randomization. At enrollment, 39% had cirrhosis and 61% had bridging fibrosis; 18%, 41%, 31%, and 10% had steatosis scores of 0, 1, 2, and 3 or 4, respectively. The mean steatosis score decreased in the follow-up biopsies in both the interferon-treated patients and controls with no effect of treatment assignment (P = 0.66). A decrease in steatosis score by > or =1 point was observed in 30% of patients and was associated with both progression to cirrhosis and continued presence of cirrhosis (P = 0.02). Compared to patients without a decrease in steatosis, those with a decrease in steatosis had worse metabolic parameters at enrollment, and were more likely to have a decrease in alcohol intake, improvement in metabolic parameters, and worsening liver disease (cirrhosis, esophageal varices, and deterioration in liver function).

CONCLUSION

Serial biopsies demonstrated that in patients with CHC, steatosis recedes during progression from advanced fibrosis to cirrhosis. Decreased alcohol intake and improved metabolic parameters are associated with a decline in steatosis and may modulate hepatitis C progression.

Phase I/II study of recombinant interferon alpha and gamma in advanced progressive renal-cell carcinoma

In vitro studies have documented the synergistic antiviral and antiproliferative activity of recombinant interferon alpha (rIFN alpha) and rIFN gamma. Furthermore, rIFN gamma is a strong immunomodulator with optimal effects at a relative low dose (0.1 mg/m2). On the basis of these observations, we began a phase I/II study with the combination of rIFN gamma at 100 micrograms/m2 (2 x 10(6) IU/m2) and rIFN alpha 2c 6 micrograms/m2 (2 x 10(6) IU/m2), injected twice a week subcutaneously. In cases of stable or progressive disease we increased the dose of rIFN alpha 2c every 2 weeks by 6 micrograms/m2 until the maximum tolerated dose was reached. A total of 32 patients with proven progressive renal-cell carcinoma were included. Of the 31 eligible patients, 21 were male and 10 female, their average age was 57.2 years (range 35-72), 28 had had nephrectomy, their median Karnofsky performance status was 90% (70%-100%), and their tumors were localized predominantly to visceral tissue. In 2, response was complete and in 6 it was partial, for a response rate of 25%. The disease had stabilized in 5 patients and progressed in 16. The median duration of partial response was 14 months (8-16 months); of 2 cases of complete response, 1 persists (23+ months), and the other suffered a relapse after 22 months. The median time to response was 24 weeks (18-24 weeks). The maximum tolerated dose of rIFN alpha was 30 micrograms/m2 (range of 6-36 micrograms/m2). Side-effects included those known to be associated with interferon treatment. One patient developed septicemia during a period with grade 4 leukopenia. Our study permits no conclusion regarding the additional value of rIFN gamma.