Hepatitis B virus (HBV) reactivation during immunosuppression can lead to severe acute hepatitis, fulminant liver failure, and death. Here, we investigated hepatitis B surface antigen (HBsAg) genetic features underlying this phenomenon by analyzing 93 patients: 29 developing HBV reactivation and 64 consecutive patients with chronic HBV infection (as control). HBsAg genetic diversity was analyzed by population-based and ultradeep sequencing (UDS). Before HBV reactivation, 51.7% of patients were isolated hepatitis B core antibody (anti-HBc) positive, 31.0% inactive carriers, 6.9% anti-HBc/anti-HBs (hepatitis B surface antibody) positive, 6.9% isolated anti-HBs positive, and 3.4% had an overt HBV infection. Of HBV-reactivated patients, 51.7% were treated with rituximab, 34.5% with different chemotherapeutics, and 13.8% with corticosteroids only for inflammatory diseases. In total, 75.9% of HBV-reactivated patients (vs. 3.1% of control patients; P < 0.001) carried HBsAg mutations localized in immune-active HBsAg regions. Of the 13 HBsAg mutations found in these patients, 8 of 13 (M103I-L109I-T118K-P120A-Y134H-S143L-D144E-S171F) reside in a major hydrophilic loop (target of neutralizing antibodies [Abs]); some of them are already known to hamper HBsAg recognition by humoral response. The remaining five (C48G-V96A-L175S-G185E-V190A) are localized in class I/ II-restricted T-cell epitopes, suggesting a role in HBV escape from T-cell-mediated responses. By UDS, these mutations occurred in HBV-reactivated patients with a median intrapatient prevalence of 73.3% (range, 27.6%-100%) supporting their fixation in the viral population as a predominant species. In control patients carrying such mutations, their median intrapatient prevalence was 4.6% (range, 2.5%-11.3%; P < 0.001). Finally, additional N-linked glycosylation (NLG) sites within the major hydrophilic loop were found in 24.1% of HBV-reactivated patients (vs. 0% of chronic patients; P < 0.001); 5 of 7 patients carrying these sites remained HBsAg negative despite HBV reactivation. NLG can mask immunogenic epitopes, abrogating HBsAg recognition by Abs. Conclusion: HBV reactivation occurs in a wide variety of clinical settings requiring immune-suppressive therapy, and correlates with HBsAg mutations endowed with enhanced capability to evade immune response. This highlights the need for careful patient monitoring in all immunosuppressive settings at reactivation risk and of establishing a prompt therapy to prevent HBV-related clinical complications. (HEPATOLOGY 2015;61:823-833)
ObjectiveThe involvement of HBV DNA integration in promoting hepatocarcinogenesis and the extent to which the intrahepatic HBV reservoir modulates liver disease progression remains poorly understood. We examined the intrahepatic HBV reservoir, the occurrence of HBV DNA integration and its impact on the hepatocyte transcriptome in hepatitis B ‘e’ antigen (HBeAg)-negative chronic hepatitis B (CHB).DesignLiver tissue from 84 HBeAg-negative patients with CHB with low (n=12), moderate (n=25) and high (n=47) serum HBV DNA was analysed. Covalently closed circular DNA (cccDNA), pregenomic RNA (pgRNA) were evaluated by quantitative PCR, whole exome and transcriptome sequencing was performed by Illumina, and the burden of HBV DNA integrations was evaluated by digital droplet PCR.ResultsPatients with low and moderate serum HBV DNA displayed comparable intrahepatic cccDNA and pgRNA, significantly lower than in patients with high HBV DNA, while hepatitis B core-related antigen correlated strongly with the intrahepatic HBV reservoir, reflecting cccDNA quantity. Whole exome integration was detected in a significant number of patients (55.6%, 14.3% and 25% in high, moderate and low viraemic patients, respectively), at a frequency ranging from 0.5 to 157 integrations/1000 hepatocytes. Hepatitis B surface antigen >5000 IU/mL predicted integration within the exome and these integrations localised in genes involved in hepatocarcinogenesis, regulation of lipid/drug metabolism and antiviral/inflammatory responses. Transcript levels of specific genes, including the proto-oncogene hRAS, were higher in patients with HBV DNA integration, supporting an underlying oncogenic risk in patients with low-level to moderate-level viraemia.ConclusionsHBV DNA integration occurs across all HBeAg-negative patients with CHB, including those with a limited HBV reservoir; localising in genes involved in carcinogenesis and altering the hepatocyte transcriptome.
Through this study we evaluated whether the HIV-1 tropism determined by genotypic analysis correlates with HIV-1 markers, such as CD4 cell count and plasma HIV-RNA. The analysis was performed on 1221 HIV-1 B-subtype infected patients with an available V3 sequence (all maraviroc naive). Of them, 532 were antiretroviral therapy (ART) naive and 689 ART experienced. Tropism determination was performed by using the geno2pheno (co-receptor) algorithm set at a false-positive rate (FPR) of 10% and 2%. Potential associations of FPR with CD4 cell count and viraemia were evaluated. Association of V3 mutations with genotypic-determined tropism was also evaluated according to different FPR ranges. About 26% of patients (either ART naive or ART experienced) were infected by X4-tropic viruses (using the classical 10% FPR cut-off). However, a significantly lower proportion of ART-naive patients had FPR ≤ 2% in comparison with ART-experienced patients (4.9% vs. 12.6%, respectively, p <0.001). The risk of advanced HIV-1 infection (with CD4 cell count ≤ 200 cells/mm(3)) was significantly greater in X4-infected patients, either ART-naive (OR (95% CI)), 4.2 (1.8-9.2); p 0.0006) or ART-experienced (2.3 (1.4-3.6); p 0.0003), with FPR set at 2% (but not at 10%). This finding was confirmed by multivariable logistic analysis. No relationship was found between viraemia and FPR ≤2%. Some X4-related mutations were significantly associated with FPR ≤2% (ART-naive patients, S11R, Y21V, G24K and G24R, p ≤0.001; ART-experienced patients, Y7K, S11R, H13Y, p ≤0.002). In conclusion, these findings show that within the context of genotypically-assessed CXCR4 tropism, FPR ≤2% defines (far better than 10%-FPR) a viral population associated with low CD4 rank, with potentially greater cytopathic effect, and with more advanced disease.
The activity of raltegravir and 4 other integrase inhibitors (MK-2048, L870,810, \ud IN2, and IN5) was investigated in primary human macrophages, PBMC and\ud C8166-lymphocytic T cells, in order to determine their relative potency and\ud efficacy in different cellular systems of HIV infection. Raltegravir showed\ud better protective efficacy in all cell types; MK-2048, L870,810 and IN5 showed a \ud potent anti-HIV-1 activity in macrophages, while in lymphocytes only MK-2048 and \ud L870,810 showed an inhibitory effect comparable to raltegravir. IN2 was a poorly \ud effective anti-HIV-1 compound in all cellular systems. All effective integrase\ud inhibitors exhibited a potent antiviral activity against both X4 and R5 HIV-1\ud strains. In general, raltegravir, MK-2048, L870,810 and IN5 showed anti HIV\ud activity similar or slightly higher in macrophages compared to PBMC and C8166 T\ud cells: for MK-2048, the EC(50) was 0.4, 0.9, 11.5nM in macrophages, in PBMCs and \ud T cells, respectively; for L870,810, the EC(50) was 1.5, 14.3, and 10.6nM,\ud respectively; for IN5 the EC(50) was 0.5, 13.7, and 5.7nM, respectively
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