[Clinical significance of toll-like receptor 4 expression on the surface of peripheral blood mononuclear cells in uremic patients].

OBJECTIVE: To explore the clinical significance of toll-like receptor 4 expression on the surface of peripheral blood mononuclear cells (PBMC) in uremic patients and observe the effect of ultrapure dialysate on the PBMC expression of TLR4 in these patients. METHODS: Eighty patients on maintenance dialysis were randomly divided into two groups: conventional dialysate group (CD, n=40), ultrapure dialysate group (UPD, n=40) and 40 uremic patients without dialysis in NHD group. The blood cells from all patients and 40 healthy controls were stained with FITC labeling anti-TLR4 monoclonal antibodies. Samples were collected and analyzed by flow cytometry. RESULTS: The expression of TLR4 was significantly lower in CD group (18.1±3.7) than in NHD group (24.5±4.6, P<0.05) and healthy control group (31.6±5.8, P<0.01). And marked difference existed between CD group (18.1±3.7) and UPD group (23.1±3.2, P<0.05) at Month 6 post-dialysis. In CD group the expression of TLR4 became significantly smaller as the duration of dialysis increased (P<0.05) while in UPD group although the expression of TLR4 became smaller as the duration of dialysis became longer. But the difference was not statistically significant (P>0.05). CONCLUSION: The PBMC expression of TLR4 becomes down-regulated in uremic patients with or without dialysis and its expression is smaller in conventional dialysate group than in ultrapure dialysate group. The conventional dialysate may suppress the expression of TLR4 while the phenomenon is absent in ultrapure dialysate group.