I'm not sure why people say bad things happen in threes, but they certainly did Tuesday.

Three companies announced they were closing local plants and laying off employees.

Hoeganaes Corp., which has been making ferrous metal powders in Cinnaminson for 55 years, said it would close the last remaining industrial operations it has there in February. Seven people will lose their jobs, while 70 will remain at its headquarters and research and development operations there.

PPG Industries Inc. , of Pittsburgh, said it would get out of the insulating glass sealants business. That means it will cease production at its Gloucester City factory March 15, costing 29 people their jobs.

Gritty businesses both, to be sure. But the third company to cut jobs is in an industry that has been one of the region's bright spots: life sciences.

WuXi AppTec, which provides testing and other outsourced services to the pharmaceutical and biotechnology industries, had grown from 40 employees to more than 260, the city of Philadelphia noted in a recent bond document.

An Inquirer story from 2004 said that city and state economic development officials hoped that the relocation of AppTec Laboratory Services, as it was known then, would help launch a biotech complex in South Philadelphia.

That ambition suffered a setback yesterday when WuXi PharmaTech (Cayman) Inc., the Shanghai-based parent of the local operations, said it would discontinue biologics manufacturing in Philadelphia and eliminate 100 jobs.

A company spokeswoman said WuXi AppTec still would employ 140 people at the Navy Yard operations after the cuts.

Judging by the questions analysts asked WuXi management, the move caught them off-guard. WuXi had bought AppTec, which also has operations in Atlanta and St. Paul, Minn., for $151 million earlier this year. One of the reasons that WuXi had cited for doing the deal was AppTec's specialty as a contract manufacturer of biologics, which are medicines made from living organisms.

But Ge Li, chairman and CEO of WuXi, said the biologics manufacturing business was "not performing to our expectations."

Many of the small biotech clients who hire WuXi AppTec to manufacture their biologics have been unable to raise capital to move forward with their early-stage drug development efforts, several WuXi executives said.

WuXi's remaining local operations include biologics testing, cell banking and cell therapy services - all expanding businesses for the Chinese company.

And Li stressed that biologics manufacturing was a small part of WuXi's business: about $10 million, or less than 4 percent of its total estimated 2008 revenue of $260 million to $265 million.

For a region that's been steadily losing its manufacturing base for the last 50 years, the loss of 136 more jobs may seem like the felling of a sapling in a clear-cut forest. But these jobs aren't going to come back here - unlike what has happened with the oil industry in Houston or the financial industry (usually) in New York.

For WuXi AppTec, not even the tax-friendly Keystone Opportunity Improvement Zone in the Navy Yard could save these jobs.