Isolation of PBMCs
PBMCs were isolated by using a modified method of GmeligMeyling and Waldmann.
Briefly, venous blood (10 mL) was obtained in heparin-containing tubes containing equal amount of physiological saline (1:1) by aseptic vein puncture from healthy human volunteers who were nonsmokers, had fasted overnight, and did not take any medicine or supplements. Written informed consent was provided for protection of the rights and welfare of human subjects involved in this
research. The diluted blood was then centrifuged at 400× g for 20 minutes after carefully layered on lymphoprep. The monocytes, formed as a distinct band at the medium interface,
were collected carefully using a Pasteur pipette. The collected