title: High-throughput sequencing analysis of post-liver transplantation HCV E2 glycoprotein evolution in the presence and absence of neutralizing monoclonal antibody.
abstract: Chronic hepatitis C virus (HCV) infection is the most common cause of end-stage liver disease, often leading to liver transplantation, in which case circulating virions typically infect the transplanted liver within hours and viral concentrations can quickly exceed pre-transplant levels. MBL-HCV1 is a fully human monoclonal antibody recognizing a linear epitope of the HCV E2 envelope glycoprotein (amino acids 412-423). The ability of MBL-HCV1 to prevent HCV recurrence after liver transplantation was investigated in a phase 2 randomized clinical trial evaluating six MBL-HCV1-treated subjects and five placebo-treated subjects. MBL-HCV1 treatment significantly delayed time to viral rebound compared with placebo treatment. Here we report results from high-throughput sequencing on the serum of each of the eleven enrolled subjects prior to liver transplantation and after viral rebound. We further sequenced the sera of the MBL-HCV1-treated subjects at various interim time points to study the evolution of antibody-resistant viral variants. We detected mutations at one of two positions within the antibody epitope--mutations of N at position 415 to D, K or S, or mutation of N at position 417 to S. It has been previously reported that N415 is not glycosylated in the wild-type E2 protein, but N417S can lead to glycosylation at position 415. Thus N415 is a key position for antibody recognition and the only routes we identified for viral escape, within the constraints of HCV fitness in vivo, involve mutating or glycosylating this position. Evaluation of mutations along the entire E1 and E2 proteins revealed additional positions that changed moderately before and after MBL-HCV1 treatment for subsets of the six subjects, yet underscored the relative importance of position 415 in MBL-HCV1 resistance.
authors: MassBiologics, University of Massachusetts Medical School, Boston, Massachusetts, United States of America.
authors: Gregory J
authors: GJ
authors: Babcock
authors: Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America; Bioinformatics Program, Boston University, Boston, Massachusetts, United States of America.
authors: Sowmya
authors: S
authors: Iyer
authors: MassBiologics, University of Massachusetts Medical School, Boston, Massachusetts, United States of America.
authors: Heidi L
authors: HL
authors: Smith
authors: MassBiologics, University of Massachusetts Medical School, Boston, Massachusetts, United States of America.
authors: Yang
authors: Y
authors: Wang
authors: MassBiologics, University of Massachusetts Medical School, Boston, Massachusetts, United States of America.
authors: Kirk
authors: K
authors: Rowley
authors: MassBiologics, University of Massachusetts Medical School, Boston, Massachusetts, United States of America.
authors: Donna M
authors: DM
authors: Ambrosino
authors: Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America.
authors: Phillip D
authors: PD
authors: Zamore
authors: Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America.
authors: Brian G
authors: BG
authors: Pierce
authors: MassBiologics, University of Massachusetts Medical School, Boston, Massachusetts, United States of America.
authors: Deborah C
authors: DC
authors: Molrine
authors: Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America.
authors: Zhiping
authors: Z
authors: Weng
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D057134:Antibodies, Neutralizing / Q000494:pharmacology*; D000914:Antibodies, Viral / Q000276:immunology; D005075:Biological Evolution; D015415:Biomarkers / Q000378:metabolism*; D004311:Double-Blind Method; D005500:Follow-Up Studies; D006031:Glycosylation; D019698:Hepatitis C, Chronic / Q000276:immunology / Q000628:therapy*; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods; D006801:Humans; D016031:Liver Transplantation; D008969:Molecular Sequence Data; D011379:Prognosis; D012367:RNA, Viral / Q000097:blood / Q000235:genetics; D012008:Recurrence; D017386:Sequence Homology, Amino Acid; D014759:Viral Envelope Proteins / Q000037:antagonists & inhibitors / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D015415:Biomarkers; D012367:RNA, Viral; D014759:Viral Envelope Proteins; C091015:glycoprotein E2, Hepatitis C virus