SAN FRANCISCO, Feb. 21 - If proteomics is on the verge of being the next big biotech thing, protein microarrays may be the next big little thing.
"The real drive is miniaturization and multiplexing and protein arrays' ability to do many experiments with a little bit of sample," said Rich Fisler, business manager of microarray instrumentation at PerkinElmer. "Last year there was a growing interest in protein microarrays, and this year it should continue." He predicts that preprinted arrays containing 15 antibodies or 100 proteins aimed at a single disease would by on the market in one year.
According to Todd Martinsky, a founder of Sunnyvale, Calif.-based TeleChem/Arrayit.com: "People are repurposing our DNA microarray products to manufacture protein microarrays." He said that phone inquiries about protein microarrays have shot from one or two calls in 2000 to hundreds of calls in 2001. Martinsky said he expects more of the same in 2002.
"The field of proteins and protein biochemistry is undergoing a revolution where traditional assays will be replaced by microarray formats," said Mark Schena, a visiting scholar at Arrayit.com. "So instead of spending 12 hours in a cold room [analyzing one protein] you can analyze 10,000 proteins in a single chip in 10 hours. It allows you to do things much more quickly and with greater precision."
In fact, a start-up company called Protometrix, based in Guilford, Conn, recently squeezed 5,800 purified yeast proteins--nearly the entire proteome--onto a single microarray. The technology, called a 'nanowell' protein array by the Yale scientist who co-developed it, took four years to create and is not yet on the market.
The process to make that array, which contains some 13,000 spots, is not automated and thus takes roughly 6 weeks. But the lead researcher, Michael Snyder, said he hopes to use inexpensive robots to speed up that process--"And I don't mean post docs," he quipped at a recent presentation in Boston last week.
Added Schena: "Initially, people said proteins were too unstable to print on microarrays. But we're finding out that's not true."
But technical success and a viable business don't always march in lock step.
"I hear a lot of talk about [protein microarrays] but nobody is making headway," said Scott Greenstone, an analyst at Thomas Weisel Partners. "People are finding out it is difficult to do. [Now it's] a lot of early stage stuff."
The obstacles, agree people in the field, are significant. Issues include purifying proteins, getting them to bind to assay surfaces and each other, and identifying specific proteins in a cell, explained Kimmen Sjolander, an assistant professor of bioengineering at Berkeley.
"It is the right task, but I don't know how soon it will be here," said Sjolander.
Greenstone said it will take at least three years before protein microarrays develop into a significant market. But when the market emerges, it could improve the bottom line for DNA chip companies rather than hurt them.
"I don't think protein microarrays will be a substitute technology for nucleic-acid microarrays, but more complementary," said Greenstone. "It could be market extending, with a company selling two products instead of one."