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Neutralizing antibodies in patients with chronic hepatitis C, genotype 1, against a panel of genotype 1 culture viruses: lack of correlation to treatment outcome.

Pedersen J, Jensen TB, Carlsen TH, Schønning K, Christensen PB, Laursen AL, Krarup H, Bukh J, Weis N - PLoS ONE (2013)

Bottom Line: The results were expressed as the highest dilution yielding 50% neutralization (NAb50-titer).However, NAb50-titers varied significantly with a mean reciprocal NAb50-titer of 800 (range: 100-6400) against DH6/JFH1 compared to a mean NAb50-titer of 50 (range: <50-400) against all other included isolates.In conclusion, pre-treatment levels of neutralizing antibodies against HCV genotype 1 isolates could not predict treatment outcome in patients with chronic HCV infection.

View Article: PubMed Central - PubMed

Affiliation: Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.

ABSTRACT
The correlation of neutralizing antibodies to treatment outcome in patients with chronic hepatitis C virus (HCV) infection has not been established. The aim of this study was to determine whether neutralizing antibodies could be used as an outcome predictor in patients with chronic HCV, genotype 1, infection treated with pegylated interferon-α and ribavirin. Thirty-nine patients with chronic hepatitis C, genotype 1a or 1b, with either sustained virologic response (n = 23) or non-sustained virologic response (n = 16) were enrolled. Samples taken prior to treatment were tested for their ability to neutralize 6 different HCV genotype 1 cell culture recombinants (1a: H77/JFH1, TN/JFH1, DH6/JFH1; 1b: J4/JFH1, DH1/JFH1, DH5/JFH1). The results were expressed as the highest dilution yielding 50% neutralization (NAb50-titer). We observed no genotype or subtype specific differences in NAb50-titers between patients with chronic HCV infection with and without sustained virologic response when tested against any of the included culture viruses. However, NAb50-titers varied significantly with a mean reciprocal NAb50-titer of 800 (range: 100-6400) against DH6/JFH1 compared to a mean NAb50-titer of 50 (range: <50-400) against all other included isolates. Subsequent studies demonstrated that the efficient neutralization of DH6/JFH1 could be linked to engineered adaptive mutations in the envelope-2 protein. In analysis of envelope 1 and 2 sequences of HCV, recovered from a subset of patients, we observed no apparent link between relatedness of patient sequences with culture viruses used and the corresponding neutralization results. In conclusion, pre-treatment levels of neutralizing antibodies against HCV genotype 1 isolates could not predict treatment outcome in patients with chronic HCV infection. High neutralization susceptibility of DH6/JFH1 could be correlated with adaptive envelope mutations previously highlighted as important for neutralization. Our study emphasizes the importance of using multiple culture viruses for neutralization studies and contributes to the current knowledge about neutralizing epitopes, important for future therapeutic- and vaccine-studies.

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Neutralization susceptibility of DH6/JFH1.The figure illustrates the neutralization susceptibility of DH6/JFH1 with and without adaptive envelope protein mutations. Dotted lines indicate the infectivity at 50% and 100% compared to virus only. A, DH6/JFH1 against three HCV-negative plasma samples in 2-fold dilution starting from 1∶50. B. DH6/JFH1 against H06, a HCV positive serum sample, in a 2-fold dilution starting from 1∶200. C. DH6/JFH1 against 3 selected plasma samples in a 2-fold dilution starting from 1∶50. D. DH6/JFH1 against purified IgG from the same selected plasma samples in 2-fold dilution starting from 200 µg/mL. E. DH6/JFH1 V157A, V787A, S905C, Q1247L against the same selected plasma samples in a 2-fold dilution starting from 1∶50. F. DH6/JFH1 V157A, V787A, S905C, Q1247L against purified IgG from the same selected plasma samples in 2-fold dilution starting from 200 µg/mL. Error bars indicate SEM of triplicate determinations.
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pone-0062674-g006: Neutralization susceptibility of DH6/JFH1.The figure illustrates the neutralization susceptibility of DH6/JFH1 with and without adaptive envelope protein mutations. Dotted lines indicate the infectivity at 50% and 100% compared to virus only. A, DH6/JFH1 against three HCV-negative plasma samples in 2-fold dilution starting from 1∶50. B. DH6/JFH1 against H06, a HCV positive serum sample, in a 2-fold dilution starting from 1∶200. C. DH6/JFH1 against 3 selected plasma samples in a 2-fold dilution starting from 1∶50. D. DH6/JFH1 against purified IgG from the same selected plasma samples in 2-fold dilution starting from 200 µg/mL. E. DH6/JFH1 V157A, V787A, S905C, Q1247L against the same selected plasma samples in a 2-fold dilution starting from 1∶50. F. DH6/JFH1 V157A, V787A, S905C, Q1247L against purified IgG from the same selected plasma samples in 2-fold dilution starting from 200 µg/mL. Error bars indicate SEM of triplicate determinations.

Mentions: For control experiments, plasma and serum from the same patient at the same time point were tested against DH6/JFH1, and no significant difference was seen testing samples from two different patients (Figure 5). To control for unspecific neutralization, all the included 1a and 1b culture viruses were tested against three HCV negative plasma samples and no neutralization ≥50% was observed. Results are shown for DH6/JFH1 in Figure 6A. At the lowest dilution of 1∶50, a 2-fold infectivity enhancement was observed in DH1/JFH1, J4/JFH1, and H77/JFH1, which is a well- described phenomenon [39], [40]. In contrast, the previously tested chronic-phase serum, H06 was able to neutralize DH6/JFH1 with a NAb50 titer of 3200 (Figure 6B).


Neutralizing antibodies in patients with chronic hepatitis C, genotype 1, against a panel of genotype 1 culture viruses: lack of correlation to treatment outcome.

Pedersen J, Jensen TB, Carlsen TH, Schønning K, Christensen PB, Laursen AL, Krarup H, Bukh J, Weis N - PLoS ONE (2013)

Neutralization susceptibility of DH6/JFH1.The figure illustrates the neutralization susceptibility of DH6/JFH1 with and without adaptive envelope protein mutations. Dotted lines indicate the infectivity at 50% and 100% compared to virus only. A, DH6/JFH1 against three HCV-negative plasma samples in 2-fold dilution starting from 1∶50. B. DH6/JFH1 against H06, a HCV positive serum sample, in a 2-fold dilution starting from 1∶200. C. DH6/JFH1 against 3 selected plasma samples in a 2-fold dilution starting from 1∶50. D. DH6/JFH1 against purified IgG from the same selected plasma samples in 2-fold dilution starting from 200 µg/mL. E. DH6/JFH1 V157A, V787A, S905C, Q1247L against the same selected plasma samples in a 2-fold dilution starting from 1∶50. F. DH6/JFH1 V157A, V787A, S905C, Q1247L against purified IgG from the same selected plasma samples in 2-fold dilution starting from 200 µg/mL. Error bars indicate SEM of triplicate determinations.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3646876&req=5

pone-0062674-g006: Neutralization susceptibility of DH6/JFH1.The figure illustrates the neutralization susceptibility of DH6/JFH1 with and without adaptive envelope protein mutations. Dotted lines indicate the infectivity at 50% and 100% compared to virus only. A, DH6/JFH1 against three HCV-negative plasma samples in 2-fold dilution starting from 1∶50. B. DH6/JFH1 against H06, a HCV positive serum sample, in a 2-fold dilution starting from 1∶200. C. DH6/JFH1 against 3 selected plasma samples in a 2-fold dilution starting from 1∶50. D. DH6/JFH1 against purified IgG from the same selected plasma samples in 2-fold dilution starting from 200 µg/mL. E. DH6/JFH1 V157A, V787A, S905C, Q1247L against the same selected plasma samples in a 2-fold dilution starting from 1∶50. F. DH6/JFH1 V157A, V787A, S905C, Q1247L against purified IgG from the same selected plasma samples in 2-fold dilution starting from 200 µg/mL. Error bars indicate SEM of triplicate determinations.
Mentions: For control experiments, plasma and serum from the same patient at the same time point were tested against DH6/JFH1, and no significant difference was seen testing samples from two different patients (Figure 5). To control for unspecific neutralization, all the included 1a and 1b culture viruses were tested against three HCV negative plasma samples and no neutralization ≥50% was observed. Results are shown for DH6/JFH1 in Figure 6A. At the lowest dilution of 1∶50, a 2-fold infectivity enhancement was observed in DH1/JFH1, J4/JFH1, and H77/JFH1, which is a well- described phenomenon [39], [40]. In contrast, the previously tested chronic-phase serum, H06 was able to neutralize DH6/JFH1 with a NAb50 titer of 3200 (Figure 6B).

Bottom Line: The results were expressed as the highest dilution yielding 50% neutralization (NAb50-titer).However, NAb50-titers varied significantly with a mean reciprocal NAb50-titer of 800 (range: 100-6400) against DH6/JFH1 compared to a mean NAb50-titer of 50 (range: <50-400) against all other included isolates.In conclusion, pre-treatment levels of neutralizing antibodies against HCV genotype 1 isolates could not predict treatment outcome in patients with chronic HCV infection.

View Article: PubMed Central - PubMed

Affiliation: Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.

ABSTRACT
The correlation of neutralizing antibodies to treatment outcome in patients with chronic hepatitis C virus (HCV) infection has not been established. The aim of this study was to determine whether neutralizing antibodies could be used as an outcome predictor in patients with chronic HCV, genotype 1, infection treated with pegylated interferon-α and ribavirin. Thirty-nine patients with chronic hepatitis C, genotype 1a or 1b, with either sustained virologic response (n = 23) or non-sustained virologic response (n = 16) were enrolled. Samples taken prior to treatment were tested for their ability to neutralize 6 different HCV genotype 1 cell culture recombinants (1a: H77/JFH1, TN/JFH1, DH6/JFH1; 1b: J4/JFH1, DH1/JFH1, DH5/JFH1). The results were expressed as the highest dilution yielding 50% neutralization (NAb50-titer). We observed no genotype or subtype specific differences in NAb50-titers between patients with chronic HCV infection with and without sustained virologic response when tested against any of the included culture viruses. However, NAb50-titers varied significantly with a mean reciprocal NAb50-titer of 800 (range: 100-6400) against DH6/JFH1 compared to a mean NAb50-titer of 50 (range: <50-400) against all other included isolates. Subsequent studies demonstrated that the efficient neutralization of DH6/JFH1 could be linked to engineered adaptive mutations in the envelope-2 protein. In analysis of envelope 1 and 2 sequences of HCV, recovered from a subset of patients, we observed no apparent link between relatedness of patient sequences with culture viruses used and the corresponding neutralization results. In conclusion, pre-treatment levels of neutralizing antibodies against HCV genotype 1 isolates could not predict treatment outcome in patients with chronic HCV infection. High neutralization susceptibility of DH6/JFH1 could be correlated with adaptive envelope mutations previously highlighted as important for neutralization. Our study emphasizes the importance of using multiple culture viruses for neutralization studies and contributes to the current knowledge about neutralizing epitopes, important for future therapeutic- and vaccine-studies.

Show MeSH
Related in: MedlinePlus