The Dow and the S&P 500 marked their highest closes in 17 months on Wednesday after a tame February inflation reading supported the Federal Reserve's renewed pledge of low interest rates.

The Dow Jones industrial average <.DJI> rose 47.69 points, or 0.45 percent, to end unofficially at 10,733.67. The Standard & Poor's 500 Index <.SPX> gained 6.75 points, or 0.58 percent, to finish unofficially at 1,166.21. The Nasdaq Composite Index <.IXIC> gained 11.08 points, or 0.47 percent, to close unofficially at 2,389.09.

(Reporting by Angela Moon; Editing by Jan Paschal)