title: High Epstein-Barr Virus Load and Genomic Diversity Are Associated with Generation of gp350-Specific Neutralizing Antibodies following Acute Infectious Mononucleosis.
abstract: The Epstein-Barr virus (EBV) gp350 glycoprotein interacts with the cellular receptor to mediate viral entry and is thought to be the major target for neutralizing antibodies. To better understand the role of EBV-specific antibodies in the control of viral replication and the evolution of sequence diversity, we measured EBV gp350-specific antibody responses and sequenced the gp350 gene in samples obtained from individuals experiencing primary EBV infection (acute infectious mononucleosis [AIM]) and again 6 months later (during convalescence [CONV]). EBV gp350-specific IgG was detected in the sera of 17 (71%) of 24 individuals at the time of AIM and all 24 (100%) individuals during CONV; binding antibody titers increased from AIM through CONV, reaching levels equivalent to those in age-matched, chronically infected individuals. Antibody-dependent cell-mediated phagocytosis (ADCP) was rarely detected during AIM (4 of 24 individuals; 17%) but was commonly detected during CONV (19 of 24 individuals; 79%). The majority (83%) of samples taken during AIM neutralized infection of primary B cells; all samples obtained at 6 months postdiagnosis neutralized EBV infection of cultured and primary target cells. Deep sequencing revealed interpatient gp350 sequence variation but conservation of the CR2-binding site. The levels of gp350-specific neutralizing activity directly correlated with higher peripheral blood EBV DNA levels during AIM and a greater evolution of diversity in gp350 nucleotide sequences from AIM to CONV. In summary, we conclude that the viral load and EBV gp350 diversity during early infection are associated with the development of neutralizing antibody responses following AIM.
  
  
  OBJECTIVE
  Antibodies against viral surface proteins can blunt the spread of viral infection by coating viral particles, mediating uptake by immune cells, or blocking interaction with host cell receptors, making them a desirable component of a sterilizing vaccine. The EBV surface protein gp350 is a major target for antibodies. We report the detection of EBV gp350-specific antibodies capable of neutralizing EBV infection in vitro The majority of gp350-directed vaccines focus on glycoproteins from lab-adapted strains, which may poorly reflect primary viral envelope diversity. We report some of the first primary gp350 sequences, noting that the gp350 host receptor binding site is remarkably stable across patients and time. However, changes in overall gene diversity were detectable during infection. Patients with higher peripheral blood viral loads in primary infection and greater changes in viral diversity generated more efficient antibodies. Our findings provide insight into the generation of functional antibodies, necessary for vaccine development.
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Eric R
authors.initials: ER
authors.lastname: Weiss
authors.affiliation: Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA.
authors.forename: Galit
authors.initials: G
authors.lastname: Alter
authors.affiliation: Infectious Diseases, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Javier Gordon
authors.initials: JG
authors.lastname: Ogembo
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Henderson
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA.|Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Barbara
authors.initials: B
authors.lastname: Tabak
authors.affiliation: Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Yasin
authors.initials: Y
authors.lastname: Bakiş
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Mohan
authors.initials: M
authors.lastname: Somasundaran
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA.|Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Manuel
authors.initials: M
authors.lastname: Garber
authors.affiliation: Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Liisa
authors.initials: L
authors.lastname: Selin
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA Katherine.luzuriaga@umassmed.edu.
authors.forename: Katherine
authors.initials: K
authors.lastname: Luzuriaga
mesh_terms: D000208:Acute Disease; D000328:Adult; D000595:Amino Acid Sequence; D057134:Antibodies, Neutralizing / Q000097:blood*; D000914:Antibodies, Viral / Q000097:blood*; D001402:B-Lymphocytes / Q000276:immunology / Q000821:virology; D001483:Base Sequence; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D002908:Chronic Disease; D003289:Convalescence; D004279:DNA, Viral / Q000235:genetics* / Q000276:immunology; D014644:Genetic Variation; D004854:Herpesvirus 4, Human / Q000235:genetics* / Q000254:growth & development / Q000276:immunology; D054884:Host-Pathogen Interactions; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000145:classification; D007244:Infectious Mononucleosis / Q000097:blood / Q000276:immunology* / Q000821:virology; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000276:immunology; D009000:Monocytes / Q000276:immunology / Q000821:virology; D010587:Phagocytosis; D061251:Primary Cell Culture; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D019562:Viral Load / Q000235:genetics / Q000276:immunology; D014763:Viral Matrix Proteins / Q000235:genetics* / Q000276:immunology
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D004279:DNA, Viral; C034059:GP 300-350, Epstein-Barr virus; D007074:Immunoglobulin G; D008562:Membrane Glycoproteins; D014763:Viral Matrix Proteins
keywords: ADCP; EBV; Epstein-Barr virus; antibodies; gp350; neutralization