title: The impact of EBV load on T-cell immunity in pediatric thoracic transplant recipients.
abstract: BACKGROUND
  Immunologic monitoring of pediatric transplant (Tx) recipients, who are at increased risk of Epstein-Barr virus (EBV)-driven posttransplant lymphoproliferative disease, is an important goal in clinical transplantation. Here, we investigated the impact of EBV load on T-cell immunity from pediatric Tx recipients, using clinically applicable tests for improved assessment of T-cell immune competence.
  
  
  METHODS
  Thirty-five asymptomatic pediatric thoracic Tx patients were categorized into three groups according to their EBV load levels as follows: undetectable viral load (UVL), chronic low viral load (LVL) and chronic high viral load (HVL). Global and EBV-specific T-cell immunity were assessed by ATP release using Cylex Immuknow and T Cell Memory assays.
  
  
  RESULTS
  UVL patients exhibited normal ATP release to Concanavalin A (ConA) and phytohemagglutinin (PHA; 190+/-86 ng/mL, 328+/-163 ng/mL) and detectable EBV-specific (37+/-34 ng/mL) ATP responses. LVL patients displayed significantly stronger responses to ConA (373+/-174 ng/mL), PHA (498+/-196 ng/mL) and EBV (152+/-179 ng/mL), when compared with UVL or to HVL patients (ConA 185+/-114 ng/mL, PHA 318+/-173 ng/mL, and EBV 33+/-42 ng/mL). Moreover, HVL patients displayed significant inverse correlation between CD4+ T-cell ATP levels and EBV loads.
  
  
  CONCLUSIONS
  Evaluation of global and EBV-specific T-cell immunity provides a rapid assessment of patients' immune competence. It is still unclear whether selective oversuppressed ATP release by CD4+ T cells reflects HVL patients at risk of posttransplant lymphoproliferative disease. Further longitudinal studies will determine the importance of Immuknow test in identifying asymptomatic HVL patients vulnerable to EBV complications.
authors: Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA.
authors: Camila
authors: C
authors: Macedo
authors: Adriana
authors: A
authors: Zeevi
authors: Carol
authors: C
authors: Bentlejewski
authors: Iulia
authors: I
authors: Popescu
authors: Michael
authors: M
authors: Green
authors: David
authors: D
authors: Rowe
authors: Louise
authors: L
authors: Smith
authors: Steve
authors: S
authors: Webber
authors: Diana
authors: D
authors: Metes
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000293:Adolescent; D000914:Antibodies, Viral / Q000097:blood; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000821:virology*; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D020031:Epstein-Barr Virus Infections / Q000175:diagnosis / Q000276:immunology / Q000821:virology*; D005260:Female; D016027:Heart Transplantation / Q000009:adverse effects*; D016041:Heart-Lung Transplantation / Q000009:adverse effects*; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D007111:Immunity, Cellular; D007156:Immunologic Memory; D016040:Lung Transplantation / Q000009:adverse effects*; D008232:Lymphoproliferative Disorders / Q000276:immunology / Q000821:virology*; D008297:Male; D016133:Polymerase Chain Reaction; D014184:Transplantation, Homologous; D019562:Viral Load; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral; D000255:Adenosine Triphosphate