Toll-Like 4 Receptor Expression on Peripheral Blood Mononuclear Cells in Renal Transplant Recipients Can Help to Indicate the Risk of Graft Deterioration in Patients Who Experienced an Episode of Symptomatic Cytomegalovirus Infection

Data binding the expression of Toll-like 4 receptor (TLR4), transplanted kidney (KT) function, and symptomatic CMV infection (CMV+) are scarcely available. To investigate the relationship between TLR4 expression (TLR4ex) in patients who had a relapse of CMV and transplant function. TLR4ex was measured in peripheral blood mononuclear cells of KT recipients. We compared TLR4ex among 30 CMV+ patients and 87 patients without CMV infection (CMVneg). At the beginning (day 0) TLR4ex, as well as concentrations of cyclosporin A and tacrolimus were determined. All patients, CMV+ and CMVneg patients were divided according to the respective median of TLR4ex into groups of low-TLR4 expression (L-TLR4ex) and high-TLR4 expression (H-TLR4ex). Estimated glomerular filtration rate (EGFR) was assessed on day 0 and after the follow-up (F-up). The magnitudes of EGFR change (ΔEGFR) were evaluated. Stable treatment along the F-up period (median 11.9 months) was applied. TLR4ex of CMV+ in 67% was below median for all patients. For day 0, in CMV+: no link of TLR4ex with EGFR was found; TLR4ex was lower but day 0 EGFR did not differ from H-TLR4ex. In CMVneg, a GFR-TLR4ex link was present. Post F-up. In CMV+ with L-TLR4ex, EGFR declined, with no change in H-TLR4ex. In CMVneg with H-TLR4ex, EGFR increased, with no change in L-TLR4ex. Both regression and receiver operating characteristic curve analyses points out the impact of CMV+ and TLR4ex on eGFR and ΔEGFR. In CMV+, low TLR4ex increases the risk of EGFR deterioration. In CMVneg, high TLR4ex raises the chance of EGFR improvement. •In kidney transplant recipients, low expression of Toll-like 4 (TLR4) receptor in peripheral blood mononuclear cells is associated with a higher percentage of individuals who have undergone an explicit relapse of cytomegalovirus (CMV) replication.•Long cold ischemia time, malnutrition, or kidney transplant failure raise the possibility of low CMV replication.•When history of CMV is associated with low TLR4 expression, they jointly constitute a risk factor for the future impairment of graft function.