title: Kinetics of Epstein-Barr virus load and virus-specific CD8+ T cells in acute infectious mononucleosis.
abstract: BACKGROUND
  During the convalescent phase of acute infectious mononucleosis (AIM), Epstein-Barr virus (EBV) load shrinks rapidly in association with a rapid decline in the number of EBV-specific CD8(+) T cells. The actual contribution of EBV-specific CD8(+) T cells in reducing EBV load, however, is not known.
  
  
  OBJECTIVE
  To clarify the impact of EBV-specific CD8(+) T cells on the contraction of EBV load in AIM, we estimated half-lives of both EBV load and EBV-specific CD8(+) T cells.
  
  
  METHODS
  Blood was serially taken from five pediatric patients with AIM during the convalescent period, including the very early phase, and both EBV load and EBV-specific CD8(+) T cell numbers were assayed.
  
  
  RESULTS
  EBV load declined rapidly (half-life 1.5 d) during the first 2 weeks after onset of symptoms. This half-life was seven-fold shorter than that reported for CD27(+) memory B cells. Subsequently, the EBV load declined much more slowly, with a half-life of 38.7 d. EBV-specific CD8(+) T cell numbers also declined concomitantly with the decrease in EBV load. The half-life of EBV-specific CD8(+) T cells during first 2 weeks was 2.9 d. The number of EBV-specific CD8(+) T cells and the rate of change of viral load correlated significantly (R(2) ≥ 0.8; p ≤ 0.02).
  
  
  CONCLUSIONS
  The short half-life of EBV load, together with the strong correlation between the number of EBV-specific CD8(+) T cells and the rate of change of viral load indicates an active role for EBV-specific CD8(+) T cells in elimination of EBV in AIM.
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Japan.
authors.forename: Yo
authors.initials: Y
authors.lastname: Hoshino
authors.forename: Kazuo
authors.initials: K
authors.lastname: Nishikawa
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ito
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Kuzushima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kimura
mesh_terms: D000293:Adolescent; D001769:Blood / Q000821:virology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D004854:Herpesvirus 4, Human / Q000302:isolation & purification*; D006801:Humans; D007244:Infectious Mononucleosis / Q000276:immunology* / Q000821:virology*; D018655:Lymphocyte Count; D019562:Viral Load