title: B-cell polyclonal activation and Epstein-Barr viral abortive lytic cycle are two key features in acute infectious mononucleosis.
abstract: BACKGROUND
  Acute infectious mononucleosis (AIM) is generally associated with a large EBV B cell reservoir cells and an intense B-cell polyclonal activation whereas the number of quiescent EBV-infected memory B cells in chronically EBV-infected healthy controls is very low.
  
  
  OBJECTIVE
  To evaluate the extent and functionality of ex vivo B-cell polyclonal activation, quantify the EBV DNA integrated in B cells, enumerate the functional EBV DNA reservoir in B cells and circulating B cells spontaneously secreting EBV antigens in AIM.
  
  
  METHODS
  Circulating B cells and B cells differentiating into plamablasts and plasma cells, early (BZLF1)- and late viral antigen (gp350)-secreting-cells (SCs) were enumerated in six AIM patients and seven healthy EBV carriers.
  
  
  RESULTS
  In vitro B-cell polyclonal activation induced 8000-24,000 BZLF1- and 1000-3000gp350-SCs/10(6) B cells, respectively. These data suggest that only 11.1-19.5% of cells expressing BZLF1 synthesized gp350 and so completed the EBV-lytic cycle. Furthermore, circulating spontaneous BZLF1- and gp350-SCs that reflect ongoing viral replication were rare (20-120 and 10-30/10(6) B cells, respectively), and their low numbers contrasted with the high levels of circulating plasma cells (1.1-10.2% of CD19(+) B cells).
  
  
  CONCLUSIONS
  The in vivo terminal-B-cell differentiation into plasma cells could unmask EBV B-cell reservoir to specific cytotoxic T-cell response and combined with a predominant abortive functional-EBV-reservoir, strongly contribute to rapid decay of cellular EBV reservoir in AIM.
authors.affiliation: Université Montpellier 1, 34967 Montpellier, France; CHU Montpellier, Département de Bactériologie-Virologie, 34295 Montpellier, France.
authors.forename: Yassine
authors.initials: Y
authors.lastname: Al Tabaa
authors.forename: Edouard
authors.initials: E
authors.lastname: Tuaillon
authors.forename: Eric
authors.initials: E
authors.lastname: Jeziorski
authors.forename: David Eric
authors.initials: DE
authors.lastname: Ouedraogo
authors.forename: Karine
authors.initials: K
authors.lastname: Bolloré
authors.forename: Pierre-Alain
authors.initials: PA
authors.lastname: Rubbo
authors.forename: Vincent
authors.initials: V
authors.lastname: Foulongne
authors.forename: Michel
authors.initials: M
authors.lastname: Rodière
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Vendrell
mesh_terms: D000208:Acute Disease; D000956:Antigens, Viral / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D020031:Epstein-Barr Virus Infections / Q000276:immunology* / Q000821:virology; D019309:Epstein-Barr Virus Nuclear Antigens / Q000276:immunology; D004854:Herpesvirus 4, Human / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007244:Infectious Mononucleosis / Q000175:diagnosis / Q000276:immunology* / Q000473:pathology; D008213:Lymphocyte Activation / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D015534:Trans-Activators / Q000032:analysis / Q000096:biosynthesis / Q000378:metabolism; D014764:Viral Proteins / Q000032:analysis / Q000096:biosynthesis / Q000378:metabolism; D000511:alpha-Macroglobulins / Q000276:immunology
chemical_list: D000956:Antigens, Viral; C063676:BZLF1 protein, Herpesvirus 4, Human; D019309:Epstein-Barr Virus Nuclear Antigens; D015534:Trans-Activators; D014764:Viral Proteins; D000511:alpha-Macroglobulins; C032306:polyclonal B cell activator