Maintenance of the EBV-specific CD8+ TCRαβ repertoire in immunosuppressed lung transplant recipients

Immunol Cell Biol. 2017 Jan;95(1):77-86. doi: 10.1038/icb.2016.71. Epub 2016 Oct 4.

Abstract

Epstein-Barr virus (EBV) is one of the most common viruses in humans, capable of causing life-threatening infections and cancers in immunocompromised individuals. Although CD8+ T cells provide key protection against EBV, the persistence and dynamics of specific T-cell receptor (TCR) clones during immunosuppression in transplant patients is largely unknown. For the first time, we used a novel single-cell TCRαβ multiplex-nested reverse transcriptase PCR to dissect TCRαβ clonal diversity within GLCTLVAML (GLC)-specific CD8+ T cells in healthy individuals and immunocompromised lung transplant recipients. The GLC peptide presented by HLA-A*02:01 is one of the most immunogenic T-cell targets from the EBV proteome. We found that the GLC-specific TCRαβ repertoire was heavily biased toward TRAV5 and encompassed five classes of public TCRαβs, suggesting that these clonotypes are preferentially utilized following infection. We identified that a common TRAV5 was diversely paired with different TRAJ and TRBV/TRBJ genes, in both immunocompetent and immunocompromised individuals, with an average of 12 different TCRαβ clonotypes/donor. Moreover, pre-transplant GLC-specific TCRαβ repertoires were relatively stable over 1 year post transplant under immunosuppression in the absence or presence of EBV reactivation. In addition, we provide the first evidence of early GLC-specific CD8+ T cells at 87 days post transplant, which preceded clinical EBV detection at 242 days in an EBV-seronegative patient receiving a lung allograft from an EBV-seropositive donor. This was associated with a relatively stable TCRαβ repertoire after CD8+ T-cell expansion. Our findings provide insights into the composition and temporal dynamics of the EBV-specific TCRαβ repertoire in immunocompromised transplant patients and suggest that the early detection of EBV-specific T cells might be a predictor of ensuing EBV blood viremia.

MeSH terms

  • Allografts / immunology
  • Amino Acid Sequence
  • CD8-Positive T-Lymphocytes / immunology*
  • DNA, Viral / blood
  • Epstein-Barr Virus Infections / blood
  • Epstein-Barr Virus Infections / immunology
  • Epstein-Barr Virus Infections / virology
  • Herpesvirus 4, Human / immunology*
  • Humans
  • Immunosuppression Therapy*
  • Lung Transplantation*
  • Peptides / metabolism
  • Receptors, Antigen, T-Cell, alpha-beta / metabolism*
  • Tissue Donors
  • Transplant Recipients*
  • Virus Activation

Substances

  • DNA, Viral
  • Peptides
  • Receptors, Antigen, T-Cell, alpha-beta