400. Relationship Between CMV-specific T-cell Immunity and Allograft Rejection in Lung Transplant Patients
Session: Poster Session: Hospital-acquired and Transplant Infections
Friday, October 30, 2009: 12:00 AM
Room: Poster Hall A
Background: In lung transplant patients (LTP), CMV causes direct and potential indirect effects, such as allograft rejection. The role of CMV-specific T-cell immunity of LTP in the context of allograft rejection is unknown. Our aim is to determine the feasibility of assessing allograft rejection risk by monitoring CMV-specific T-cell responses.
Methods: To evaluate CMV-specific T-cell responses, we used a monocyte-derived dendritic cell (MDDC) assay. Autologous monocytes were cultured for 7 days to derive DCs and then infected with TB40/E strain of human CMV. CMV-infected MDDCs were co-cultured with autologous PBMCs, and cells were stained for IFN-γ, CD69 and appropriate surface markers for flow cytometry analysis.
Results: We compared the patterns of CMV-specific (CMV-sp) T-cell immunity in D+/R+ LTR with rejection compared to no rejection. By 3 months post-transplant, CMV-sp T-cells were higher in patients with no rejection (below table).
No RejectionCMV-sp CD4 (cells/ml)CMV-sp CD8 (cells/ml)
Patient 112 77828 934
Patient 25026697
Patient 362 5664372
Rejection
Patient 41800
Patient 524795798

For patients with rejection, an increase in CMV-sp CD8 T-cells was detected prior to allograft rejection (5-fold for Number 4 and 9-fold for Number 5). Only Number 4 had CMV infection and had the lowest quantity of CMV-sp T-cells. We also compared patterns of CMV-sp T-cell immunity in 3 D+/R- LTR. By ≥6 months post-transplant, no rejection patients had higher CMV-sp CD8 T-cell responses (Number 6: pre-767; post-3508 cells/ml. Number 7: pre-1041; post-1538). In contrast, patient 8 with rejection remained at low responses (pre-549; post-26). Only Number 7 had CMV infection and developed a CMV-sp CD4 T-cell increase prior to CMV detection.
Conclusions: Monitoring CMV-specific T-cell responses can be useful to assess the risk of allograft rejection in LTR.
Sharon Chen, MD1, Vivian de Leon, BS2, Gundeep Dhillon, MD2, David Lewis, MD2, Lan Liu, BS2, David Weill, MD2 and  S. F. Chen, None..
L. X. Liu, None..
G. Dhillon, None..
V. de Leon, None..
D. Weill, None..
D. B. Lewis, None., (1)Westmead Hospital, Westmead, NSW, Australia, (2)Stanford University School of Medicine, Stanford, CA