The 30-share BSE Sensex closed 273.55 points or 0.35 per cent higher at 77,928.15. The 50-share NSE Nifty was up by 66.95 points or 0.28 per cent and ended the session at 24,317.15. Among sectoral indices, Nifty Auto gained over 1.63 per cent, followed by Nifty IT and Nifty Metal. Top gainers and losersAmong the 30-Sensex firms, Mahindra & Mahindra, Maruti, Reliance, Power Grid and Tech Mahindra were the major gainers, with M&M gaining 2.01 per cent today. Today, shares of 15 out of 30 Sensex companies closed in the green, while the remaining 15 closed in the red.