Expression pattern of co-inhibitory molecules on CMV-specific T-cells in lung transplant patients.

OBJECTIVES: Cytomegalovirus infection (CMVi) occurs frequently in transplant patients. Co-inhibitory molecules on CMV-specific T-cells (TCMV) in patients after lung transplantation were investigated. METHODS: 59 lung transplant patients were stratified according to anti-CMV serostatus at time of transplantation. The co-inhibitors Programmed-Death-Receptor-1 (PD1) and B-and-T-Lymphocyte-Attenuator (BTLA) were detected on TCMV by flow cytometry (FACS). RESULTS: TCMV were detectable in CMV sero-positive patients (R+) and in CMV sero-negative patients with a lung graft of a CMV sero-positive donor (D+/R-); in both cases, the frequency of TCMV was higher than in healthy controls (HC). PD-1 on TCMV was increased in D+/R+ and D+/R- patients as compared to HC. BTLA was significantly enhanced on TCMV of D+/R- patients vs. HC. R+ patients with CMV reactivation in the past had an increased fraction of BTLA+ TCMV. CONCLUSION: In conclusion, the expression pattern of co-inhibitory molecules on TCMV is altered in patients after lung transplantation.