Cellomics this week won a US patent protecting methods that promise to increase the throughput and multiplexing potential of high-content cell-based screening assays by enabling researchers to eliminate extraneous information from images and “hone in” on hits.
Beside enhancing the Fisher unit’s extensive HCS-related intellectual property portfolio, the patent may provide the company extended patent protection on certain drug discovery-related HCS applications when its original HCS patents eventually begin to expire, company officials told CBA News this week.
The methods protected by the patent also highlight the types of techniques pharmas are looking for as they increasingly lean on HCS tools earlier in the drug-discovery process, Cellomics said.
The patent, US No. 7,085,765, entitled “Methods to increase the capacity of high content cell-based screening assays,” was originally filed in March 2002. Since that time, Cellomics has put many of the specific techniques described in the patent in the hands of its customers to increase their HCS workflow, Cellomics’ president and CEO Dan Calvo said, but the actual issued patent enhances the commercial viability of the methods.
“Our goal is to help with the workflow of customers employing cell-based imaging assays,” he said. “Our goal is not uniquely around primary and then follow-up hits – it’s the entire workflow, whether it’s up-front target ID and validation all the way through to ADME/Tox. This patent covers just one of the areas and [describes] some unique techniques that obviously seem to warrant patentable coverage that we hope to bring to the marketplace.”
Cellomics’ original HCS-related patent, No. 5,989,835, was issued in the US in 1999 and covers many of the techniques invented by Cellomics co-founders Lans Taylor and Terry Dunlay. The company has since won at least 18 additional US patents, each addressing specific applications or techniques related to the technology described in the ‘835 patent.
A Cellomics official who requested anonymity said the latest patent strengthens Cellomics’ HCS IP position because it lends additional capabilities to the core group of patents. “And of course, patents only last so many years, and this one will be enforced when some of the earlier ones have expired,” the official added.
According to its abstract, the ‘765 patent broadly protects techniques that allow multiple high-content cell-based screening assays to be pooled and primary screens to be carried out in one or more channels of a fluorescence detection device, thereby increasing the number of simultaneous screening events that can be carried out.
In addition, the patent broadly protects a method in which the deconvolution of “hits,” or images in which a test compound caused a change in fluorescence in the cell, enables a “much more rapid generation of screening data than was previously possible, and at significantly reduced costs.”
“Basically you eliminate the need to do lots of analyses on wells that are negative, and are able to focus your attention and time and workflow on the ones that are positive for at least one of the things you’re measuring.”
More specifically, according to the Cellomics official, “it’s a technique for setting up the instructions to the system in terms of what channels and which wells to read, and when, so basically you eliminate the need to do lots of analyses on wells that are negative, and are able to focus your attention and time and workflow on the ones that are positive for at least one of the things you’re measuring.”
Therefore the methods at least partially address the fact that while the enormous amounts of data generated in image-based high-content screening assays can be a boon for discovery, they can also be overwhelming.
Many pharmaceutical companies have been adopting HCS as a way to glean more and more relevant information about compounds earlier in the drug-discovery process. But as with high-throughput biochemical assays, only a very small number of hits are achieved – about 0.1 percent to 1 percent of all compounds screened, Cellomics claims in the patent. Therefore, the vast majority of wells screened in a microplate format yield a negative response, the patent states.
“With HCS, maybe the number of compounds you screen is less, but the information you get per compound is orders of magnitude greater,” Judy Masucci, Cellomics’ director of marketing, said. “A lot of customers are changing the way they do screening and doing what we like to call intelligent screening, rather than fast screening.
“They’re getting a lot of information about each compound, and in some cases, they’re almost combining primary and secondary screening into one step,” she added. “This allows them to take a quick pass at everything, and then hone in on the things of interest.”