Invitrogen launches Human ProtoArray

ARLINGTON, Va.—Putting the entire human proteome on a chip is not yet a technical reality. However, a new product on the market appears to set a path in that direction. With more than 1,800 proteins tethered to its surface, Invitrogen's Human ProtoArray still has a way to go, but its availability marks the commercial debut of high-density protein microarrays.

"It very broadly represents the major protein classes," says Paul Predki, vice president of Invitrogen's protein microarray center. "There is nothing else like it on the market right now."

The product was launched in November and, according to Predki, is already generating a significant response. "We are very pleased with the trend we are seeing, the ramp up in interest" he says. "I don't get much sleep."

Invitrogen chairman and CEO Gregory Lucier suggests the company is hoping the protein array market will follow a path like that of the half-billion dollar plus DNA microarray segment, which got started in the mid-1990s and is now poised for continued growth as it enters the $20-billion in vitro diagnostics sector.

Invitrogen entered the protein microarray arena in April 2004 when it acquired the Connecticut-based biotechnology company ProtoMetrix. In June, Invitrogen applied ProtoMetrix's proprietary array manufacturing technology to launch the Yeast ProtoArray, containing a majority of the Saccharomyces cerevisiae proteome.

The company plans to release updated versions of the human ProtoArray with "ever-increasing numbers of proteins" throughout 2005, Predki says. As part of this process, the firm recently licensed the rights to specific fields of use for more than 30 protein microarray design-related patents from the privately held biotechnology company Zyomyx.

The human ProtoArray is the first of the product line that is broadly applicable to the needs of the commercial drug discovery market, Predki says. And, he suggests, Invitrogen is intent on attracting a strong customer base in the pharmaceutical and biotechnology industries.

High-throughput probing of small molecule-protein interactions–to identify targets or to determine off-target binding–is one obvious and important set of applications for drug discovery customers. Another is enzyme substrate identification for drug target discovery. Substantial business has resulted from companies interested in screening for substrates of potential kinase targets, Predki says.

"We were a little surprised by the level of interest that we have had in that specific application," he admits. In response, Invitrogen will be releasing a reagent kit product in the coming year expressly designed to perform ProtoArray kinase screens. And Predki expects that interest for similar assays for other pharmaceutically important enzymes will develop in the near future. Invitrogen is also working with academic customers to develop novel ProtoArray applications for more exploratory research goals.

For instance, Anthony Koleske, professor of molecular biophysics and biochemistry at Yale University is applying the human ProtoArray to identify components of a signaling pathway that regulates neural development. "These high-density arrays give us a very sensitive assay to identify pathway components that can not be found using more traditional approaches," Koleske says.

At more than $1,000 per array and almost $3,000 for a protein-protein interaction assay kit, Predki admits the cost of the technology, particularly for academic scientists, can be an issue. But he points to the cost-effectiveness inherent in a product that allows a researcher to perform not one, but 1800 simultaneous experiments.