The Los Angeles Business Journal’s index of the largest local public companies was down for the week as both the Dow Jones Industrial Average and the S&P 500 posted their biggest percentage one-day drops since November 2011.

The weighted LABJ index fell 6 percent to close at 222, with losers outpacing gainers 129 to 22. Seven companies closed the week unchanged.

Among stocks trading above a dollar, MRV Communications Inc. was one of the week’s leading gainers. Shares of the Chatsworth provider of telecom equipment and services bucked the trend to finish the week up 14 percent to close at $19.14, though it did give back some gains after rising 50 percent earlier in the week..

Digital media firm Point.360 was another winner this week. Shares rose 12 percent to close at $1.15 Friday. Billionaire Patrick Soon-Shiong’s clinical-stage immunotherapy firm NantKwest Inc. was also one of this week’s leading gainers. Shares of the company rose 5 percent, closing at $23.80 Friday. The company, which debuted on the Nasdaq last month, is nevertheless trading below its $25-a-share IPO price.

Agricultural biotech Ceres Inc. was among the week’s losing stocks. Shares of the company fell 35 percent for the week, to close at $1.10. The fall came after the company said it had agreed to sell nearly 1.6 million shares of common stock at $1.22 a share and warrants to buy another 1.2 million shares.