- Email: [email protected]
Quantification of Hepatitis B Core-Related Antigen is More Useful than Quantitative HBSAG for Identification of Inactive HBSAG Carriers
POSTER PRESENTATIONS Conclusions: 1) ARC was well tolerated 2) ARC + ETV acted synergistically to produce rapid DNA suppression 3) ARC effectively inhibited cccDNA-derived mRNA with protein KD up to 2.0 logs (99%) observed 4) In HBeAg-pos naïve CHB all viral antigens were effectively suppressed, while in HBeAg-neg less KD in qHBsAg was observed compared to qHBcrAg. 5) These findings are consistent with more cccDNA-driven antigen production in naïve HBeAg-pos and a higher fraction of qHBsAg production from integrated DNA in HBeAgneg 6) These variations in viral protein KD are consistent with ARC data from chimps showing higher fractions of integrated DNAderived viral mRNA in HBeAg-neg 7) Chronic ARC studies aimed at producing HBsAg seroclearance are ongoing. THU-194 QUANTIFICATION OF HEPATITIS B CORE-RELATED ANTIGEN IS MORE USEFUL THAN QUANTITATIVE HBSAG FOR IDENTIFICATION OF INACTIVE HBSAG CARRIERS M.R. Barciela1,2, M. Bes3, M. Homs2,4, D. Tabernero2,4, R. Casillas4, S. Sauleda3, L. Nieto4, F. Rodríguez-Frías2,4, R. Esteban1,2, M. Buti1,2. 1 Liver Unit, Internal Medicine Department, Vall d’Hebron Hospital, Barcelona; 2Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid; 3Transfusion Safety Laboratory, Banc de Sang i Teixits, Servei Català de la Salut; 4Liver Pathology Unit, Departments of Biochemistry and Microbiology (Virology Unit), Vall d’Hebron Hospital, Barcelona, Spain E-mail: [email protected] Background and Aims: Hepatitis B core-related antigen is a new serological marker that has been correlated with HBV DNA and cccDNA levels. The aim of this study was to assess HBcrAg levels and contrast them with HBsAg levels in a cohort of well-documented chronic hepatitis B carriers. Methods: 123 patients hepatitis B inactive carriers HBeAg negative, normal ALT levels and HBV DNA <20,000 IU/mL were included (58% male, 73% caucasian, mean age 47 ± 14 years and HBV genotype A = 58%, D = 23%, B or C = 1%, E = 11%, H or F = 7%; in 18 cases not available). Quantitative levels of core-related antigen were performed by the electrochemioluminiscense Lumipulse® G HBcrAg assay (Fujirebio Europe, Gent, Belgium). This technique simultaneously determines denatured HBeAg, HBcAg and the precore protein p22cr. HBsAg levels were quantified by electrochemiluminescence Elecsys HBsAg II. Table: HBsAg, HBV DNA and HBcrAg levels according to HBV genotype
HBV DNA, logIU/mL HBsAg, logIU/mL HBcrAg, logU/mL
GT A N = 61
GT D N = 24
GT E N = 12
GT H or F GT N/A N=7 N = 18
2.6 ± 0.7
2.5 ± 0.8
2.6 ± 0.7
2.9 ± 0.8
2.4 ± 0.5
0.7
3.4 ± 0.8
2.7 ± 1
3.4 ± 0.8
4.1 ± 0.6
2.6 ± 1.5
<0.001
2.3 ± 0.5
2.2 ± 0.4
2.2 ± 0.3
2±0
2 ± 0.1
0.3
Conclusions: Hepatitis B core-related antigen levels are lower in inactive chronic HBV carriers. HBcrAg may be a useful tool for identification of HBV inactive carriers regardless of HBV genotype. THU-195 HEPATITIS DELTA VIRUS EVOLUTION RATE IS HIGH IN PATIENTS WITH CHRONIC DELTA INFECTION, BUT TENDS TO STABILIZE OVER TIME M. Homs1,2, F. Rodriguez-Frias1,3, J. Gregori4, R. Casillas2,4, P. Reimundo3, A. Ruiz3, C. Godoy1,2, D. Tabernero1,2, J. Quer1,4, M. Riveiro-Barciela1,5, R. Esteban1,5, M. Buti1,5. 1CIBERehd, Instituto de Salud Carlos III; 2Microbiology; 3Biochemistry, Hospital Vall d’Hebron; 4 Liver Diseases, Vall d’Hebron Research Institute; 5Hepatology, Hospital Vall d’Hebron, Barcelona, Spain E-mail: [email protected] Background and Aims: Hepatitis delta virus (HDV), the cause of a severe type of viral hepatitis, has a 1.7-kb RNA genome. A high viral evolution rate (accumulation of mutations over time) enables adaptation to the host environment. Evolution rates in RNA viruses range from 10−2 to 10−5 substitutions/site/year, the main contribution being the viral polymerase error rates; however, HDV replicates by host enzymes. The non-edited genomes (UAG in 196) encode the small delta antigen, and edited genomes (UGG in 196) encode the large delta antigen. These antigens play different, essential roles in the HDV cycle. This study aimed to establish the HDV evolution rate in patients with chronic hepatitis delta infection, followed-up >10 years. Methods: Twenty-nine sequential serum samples from 3 patients with chronic hepatitis delta were selected: HDV-RNA ≥4.5 log copies/ mL and no other viral coinfections. All were HDV genotype 1, HBeAgnegative, and had HBV-DNA ≤ 2,000 IU/mL. The HDV genome region encompassing positions 910–1270 (HDV antigen region) underwent deep sequencing (mean, 10 samples/ patient). The evolution rate was calculated by counting all substitutions detected in each sequential sample from each patient, with respect to the main sequence in the first sample from each patient, and dividing by the length of the region analysed and the time between samples. Evolution rates were assessed independently in non-edited and edited genomes. Results: 121,116 sequences were analysed (mean, 4176 sequences/ sample). The median evolution rate of the HDV region was 1.9 × 10−3 substitutions/site/year (range, 9.5 × 10−3–1.2 × 10−3 substitutions/ site/year). The evolution rate showed a significant negative correlation with the time of follow-up (Figure).
p
Mean ± SD GT, genotype; N/A, not available.
Results: Overall, mean HBcrAg was 2.2 ± 0.4 logU/mL, HBsAg 3.1 ± 1 logIU/mL and HBV DNA 2.6 ± 0.7 logIU/mL. HBcrAg levels were statistically lower in patients with HBV DNA <2,000 IU/mL in comparison with subjects with HBV DNA ≥2,000 IU/mL (HBcrAg 2.1 vs 2.5 logU/mL, p = 0.004). HBcrAg levels did not vary among the different HBV genotypes (Table). An HBcrAg cut-off of 3 logU/mL has a sensitivity of 97% and diagnostic accuracyof 85% for identification of patients with HBV DNA <2,000 IU/mL. HBsAg levels were lower in patients with HBV DNA <2,000 IU/mL compared to those with HBV DNA ≥2,000 IU/mL (3.1 vs 3.8 logUI/mL, p = 0.002). HBsAg levels varied among the different HBV genotypes (Table). Only 41% of patients with HBV DNA < 2,000 IU/mL met the criteria for identification of inactive carrier (HBsAg < 3 logIU/mL).
Median evolution rates in both non-edited and edited genomes ranged from 6.6 × 10−3 to 0.2 × 10−3 substitutions/site/year. However, paired-samples analysis showed that non-edited genomes had higher evolution rates than edited ones ( p = 0.002). The evolution rates of the two genomes also negatively correlated with the time of follow-up ( p < 0.001). Conclusions: The evolution rate is high in the HDV region studied, with levels similar to or higher than other RNAviruses, such as HCV or HIV. However, the rate appears to stabilize over time. (Study funded by Instituto de Salud Carlos III (grant PI14/1416), cofinanced by the ERDF).
Journal of Hepatology 2016 vol. 64 | S213–S424
S391
HBV DNA, logIU/mL HBsAg, logIU/mL HBcrAg, logU/mL
GT A N = 61
GT D N = 24
GT E N = 12
GT H or F GT N/A N=7 N = 18
2.6 ± 0.7
2.5 ± 0.8
2.6 ± 0.7
2.9 ± 0.8
2.4 ± 0.5
0.7
3.4 ± 0.8
2.7 ± 1
3.4 ± 0.8
4.1 ± 0.6
2.6 ± 1.5
<0.001
2.3 ± 0.5
2.2 ± 0.4
2.2 ± 0.3
2±0
2 ± 0.1
0.3
Conclusions: Hepatitis B core-related antigen levels are lower in inactive chronic HBV carriers. HBcrAg may be a useful tool for identification of HBV inactive carriers regardless of HBV genotype. THU-195 HEPATITIS DELTA VIRUS EVOLUTION RATE IS HIGH IN PATIENTS WITH CHRONIC DELTA INFECTION, BUT TENDS TO STABILIZE OVER TIME M. Homs1,2, F. Rodriguez-Frias1,3, J. Gregori4, R. Casillas2,4, P. Reimundo3, A. Ruiz3, C. Godoy1,2, D. Tabernero1,2, J. Quer1,4, M. Riveiro-Barciela1,5, R. Esteban1,5, M. Buti1,5. 1CIBERehd, Instituto de Salud Carlos III; 2Microbiology; 3Biochemistry, Hospital Vall d’Hebron; 4 Liver Diseases, Vall d’Hebron Research Institute; 5Hepatology, Hospital Vall d’Hebron, Barcelona, Spain E-mail: [email protected] Background and Aims: Hepatitis delta virus (HDV), the cause of a severe type of viral hepatitis, has a 1.7-kb RNA genome. A high viral evolution rate (accumulation of mutations over time) enables adaptation to the host environment. Evolution rates in RNA viruses range from 10−2 to 10−5 substitutions/site/year, the main contribution being the viral polymerase error rates; however, HDV replicates by host enzymes. The non-edited genomes (UAG in 196) encode the small delta antigen, and edited genomes (UGG in 196) encode the large delta antigen. These antigens play different, essential roles in the HDV cycle. This study aimed to establish the HDV evolution rate in patients with chronic hepatitis delta infection, followed-up >10 years. Methods: Twenty-nine sequential serum samples from 3 patients with chronic hepatitis delta were selected: HDV-RNA ≥4.5 log copies/ mL and no other viral coinfections. All were HDV genotype 1, HBeAgnegative, and had HBV-DNA ≤ 2,000 IU/mL. The HDV genome region encompassing positions 910–1270 (HDV antigen region) underwent deep sequencing (mean, 10 samples/ patient). The evolution rate was calculated by counting all substitutions detected in each sequential sample from each patient, with respect to the main sequence in the first sample from each patient, and dividing by the length of the region analysed and the time between samples. Evolution rates were assessed independently in non-edited and edited genomes. Results: 121,116 sequences were analysed (mean, 4176 sequences/ sample). The median evolution rate of the HDV region was 1.9 × 10−3 substitutions/site/year (range, 9.5 × 10−3–1.2 × 10−3 substitutions/ site/year). The evolution rate showed a significant negative correlation with the time of follow-up (Figure).
p
Mean ± SD GT, genotype; N/A, not available.
Results: Overall, mean HBcrAg was 2.2 ± 0.4 logU/mL, HBsAg 3.1 ± 1 logIU/mL and HBV DNA 2.6 ± 0.7 logIU/mL. HBcrAg levels were statistically lower in patients with HBV DNA <2,000 IU/mL in comparison with subjects with HBV DNA ≥2,000 IU/mL (HBcrAg 2.1 vs 2.5 logU/mL, p = 0.004). HBcrAg levels did not vary among the different HBV genotypes (Table). An HBcrAg cut-off of 3 logU/mL has a sensitivity of 97% and diagnostic accuracyof 85% for identification of patients with HBV DNA <2,000 IU/mL. HBsAg levels were lower in patients with HBV DNA <2,000 IU/mL compared to those with HBV DNA ≥2,000 IU/mL (3.1 vs 3.8 logUI/mL, p = 0.002). HBsAg levels varied among the different HBV genotypes (Table). Only 41% of patients with HBV DNA < 2,000 IU/mL met the criteria for identification of inactive carrier (HBsAg < 3 logIU/mL).
Median evolution rates in both non-edited and edited genomes ranged from 6.6 × 10−3 to 0.2 × 10−3 substitutions/site/year. However, paired-samples analysis showed that non-edited genomes had higher evolution rates than edited ones ( p = 0.002). The evolution rates of the two genomes also negatively correlated with the time of follow-up ( p < 0.001). Conclusions: The evolution rate is high in the HDV region studied, with levels similar to or higher than other RNAviruses, such as HCV or HIV. However, the rate appears to stabilize over time. (Study funded by Instituto de Salud Carlos III (grant PI14/1416), cofinanced by the ERDF).
Journal of Hepatology 2016 vol. 64 | S213–S424
S391