Abstracts (complete list) - Wissenschaft Online

Jan Dirks, Urban Sester, Daniela Presser, Heinrike Wilkens, Hans Köhler, Martina Sester
PD-1 expression on CMV specific CD4 T cells is associated
with viremia and reversible functional anergy in patients after
organ transplantation
Recently, chronic infections with LCMV, HIV or HCV were shown to be associated with
anergic T cells characterised by high expression of PD-1. We have previously shown that
uncontrolled CMV replication after transplantation correlates with a drop in CMV specific
T cells. This study was extended to analyse whether functional anergy of specific T cells
in individuals with and without CMV viremia may affect control of CMV replication.
CMV specific CD4 T cells from 12 controls, 25 hemodialysis patients, 43 renal and 14
lung-transplant patients were quantified using flow cytometry and analysed for their
expression of PD-1 and cytokines IFNγ and IL2. Specific proliferation was analysed by
CFDA-SE dilution. CMV-DNA was quantified using PCR.
In viremic patients, a significantly higher proportion of CMV specific CD4 T cells were PD-
1 positive (median 42.3%) as compared to non-viremic patients (7.4%), hemodialysis
patients (8.8%) or controls (3.1%, p=0.001). In line with functional impairment, PD-1
positive T cells produced significantly less IFNγ as compared to PD-1 negative cells (MFI
101 vs. 210, p