Increased levels of PD ‐1 expression on CD 8 T cells in patients post‐renal transplant irrespective of chronic high EBV viral load

• Published in: Pediatric transplantation Vol. 17; no. 8; pp. 806 - 814
• Main Authors: Moran, Julie, Dean, Jonathan, De Oliveira, Andre, O'Connell, Marie, Riordan, Michael, Connell, Jeff, Awan, Atif, Hall, William W., Hassan, Jaythoon
• Format: Journal Article
• Language: English
• Published: 01-12-2013
• ISSN: 1397-3142; 1399-3046
• DOI: 10.1111/petr.12156

Abstract
Studies have identified solid organ transplant recipients who remain asymptomatic despite maintaining CHL. Factors which determine the
CHL
state remain poorly understood but are likely to involve immunological control of the viral infection. We monitored expression of
PD
‐1, a marker of
T
‐cell exhaustion and viral persistence, on
CD
8 T cells in patients who resolved
EBV
infection as determined by undetectable
EBV DNA
(
REI
) and
CHL
patients.
PD
‐1 expression on
CD
8
T
cells was increased in the first year post‐transplant irrespective of
EBV
outcome, and most
CD
8
T
cells continued to express
PD
‐1 for up to three yr post‐transplant. Although all patient groups showed similar frequencies of
EBV
‐specific
CD
8+
T
cells,
PD
‐1 expression on these cells increased in the post‐transplant groups compared with the pretransplant patients. Functional studies of
EBV
‐specific
CD
8+
T
cells stimulated with
BZLF
or
LMP
2 peptide pools revealed monofunctional
IFN
‐γ responses. Our results indicate that
PD
‐1 expression on
CD
8
T
cells post‐transplant may result from factors other than antigenic stimulation.