The effects of rhBMP-2 and Treg/Th17 functional disequilibrium in uremic patients with cardiovascular complication after maintenance hemodialysis.

Objective: We compared the correlation of regulatory T cell (Treg) and Th17 cell function disequilibrium with calcification in uremic patients on maintenance hemodialysis (MHD) with healthy controls, and investigated if their influence possibly increased the development and outcome of cardiovascular complications in uremic patients after MHD.

Methods: The extent of coronary artery calcification was assessed by coronary artery calcification scoring (CACS) in uremic patients with and without adverse cardiovascular events after MHD (MHD group 1 vs. MHD group 2, respectively). Peripheral blood mononuclear cells were incubated with rhBMP-2 as positive control. The Treg/Th17 cell frequencies, Foxp3 ROR-gt mRNA expressions, and MIP 3α/CCL20 concentrations were measured.

Results: The CACS score was significantly higher in MHD group 1 as compared group 2. In comparison with controls, rhBMP-2 upregulates Treg/Th17 functional disequilibrium in uremic patients, displayed higher Treg and Th17 frequencies, Foxp3 and ROR-gt expressions, and MIP3α/CCL20 concentrations. However, the up-regulations of Treg frequencies and Foxp3 expressions were significant in controls but not in MHD patients. It was also observed that Treg/Th17 functional disequilibrium was not only correlated with rhBMP-2 state but also consistent with the cardiovascular complications. Moreover, the CACS was negatively correlated with Treg cell frequencies but positively correlated with Th17 cell frequencies and MIP3a/CCL20 concentrations.

Conclusions: Function disequilibrium of Treg/Th17 was related to the degree of the rhBMP-2 state. Function disequilibrium of the Treg/Th17 might act synergistically with rhBMP-2 in the high incidence of immune-mediated cardiovascular complications after MHD.