Looking to increase growth in its proteomics business, Invitrogen will roll out the fourth version of its ProtoArray protein chip by the end of this year, according to a company official.
Paul Predki, vice president of proteomics R&D at Invitrogen, told ProteoMonitor's sister publication BioArray News last week that the company expects to launch version 4.0 of its ProtoArray Human Protein Microarray within the next six months, although he declined to provide a specific date.
"We expect to have another protein array launched this year with significantly more content. Sometime in the fall is the expectation," he said.
The chip will contain an increase in proteins, including more kinases and druggable content that pharmaceutical customers demand, and will be the fourth in a series of ProtoArrays the company has launched since November 2004 (see ProteoMonitor 11/26/2004).
"Version 1.0 had about 1,800 proteins and Version 2.0 had just over 3,000. Version 3 has 5,000. Using that you might be able to extrapolate what version 4.0 might look like," Predki said. He declined to name a specific number of proteins for ProtoArray version 4.0.
"To some extent, there's just an attempt to get as many proteins representative of the proteome as we can onto the array. At the same time, there has been an increasing focus on ensuring that we've got druggable content on the arrays, primarily kinases, but expanding out to other classes as well."
Invitrogen relies on a "combination of two things" to determine which proteins it includes on its arrays, Predki said. "To some extent, there's just an attempt to get as many proteins representative of the proteome as we can onto the array. At the same time, there has been an increasing focus on ensuring that we've got druggable content on the arrays, primarily kinases, but expanding out to other classes as well."
Other companies in the protein array arena have chosen to provide chips that focus on specific proteomic content. Last October, for example, Sigma-Aldrich launched its Panorama Human Cancer Version 1 Protein Functional Microarray, intended solely for cancer studies (see BAN 10/12/2005).
Invitrogen has decided to avoid the model of releasing more specific chips, and will stick to its proteome-wide offering, according to Predki. Still, he said that Invitrogen does provide kinase chips on a "custom and a collaborative basis."
Selling to Pharma
Predki said that ProtoArray's target customers are "primarily pharmaceutical customers and some larger academic groups" and added that the new chip has been developed specifically to suit pharma's needs.
"We are getting a better sense of the applications that pharma, in particular, values," he said. "The dominant ones are around small-molecule profiling of various sorts," he said, adding that a second major application area is biomarker profiling.
Still, even two years after the initial release of ProtoArray, Predki said that the protein array industry is still in a period of "early adoption" and acknowledged that there are some questions about the quality of protein arrays on the market.
Similarly, Brent Keller, general manager and vice president of commercial operations at Kreatech Biotechnology, a Dutch reagents company, recently said that the protein array market is "still developing quite slowly" mostly due to "some of the questions surrounding the quality and specificity of the array itself" (see BAN 6/6/2006).
"The bottom line is that when you have 5,000 proteins on an array, generating high-quality validated content for that number of proteins is a huge challenge. That is well-recognized," Predki said about the concerns.
"This is a new and developing market and in many cases, what we do see is that people need to use these and have the value demonstrated for them, [but] we can't guarantee that every protein on our arrays will be properly folded and functional," he said. "For a large number of these proteins we don't even know their functions, so there's nothing to assay, if you will."
Predki said that the protein array market requires "a couple of really big success stories" in order to experience rapid growth.
"What we really need to see in the pharmaceutical industry is [the] use [of] these arrays to solve a problem, [and] answer a question that can't be answered by any other method," Predki said.
• Justin Petrone ([email protected])
This article originally appeared in ProteoMonitor's sister publication, BioArray News.