Drug Discovery

There is a good article in “The Scientist” this month that covers how various labs have improved the throughput for their flow cytometry applications. The piece covers some of the problems users experience with flow cytometry, namely its time-consuming nature, as well as the steps that actual users have taken to improve the process for themselves.

Flow cytometry is a commonly used technique for performing cell counts and diagnosing diseases including leukemia. The use of flow cytometry to analyze cells in the fields of immunology research and drug discovery is growing thanks to new equipment that streamlines the process. A few of these solutions can cost tens or hundreds of thousands of dollars, so some of this equipment probably won’t be a feasible option for everyone. A less intensive-option that can improve processing speed is to outfit instruments with a well-plate sipper that can accept microtiter plates, such as the Empore 96-Well Solid Phase Extraction plates. The best solution will likely depend on the number of samples being processed by flow cytometry. As Steve McCellan, Senior Biological Scientist at the University of Florida, points out in the article, “Your arm would be paralyzed” if you had to test 20,000 samples with a normal flow cytometer.

You can read the full article online here to find out what else the pros have to say about flow cytometry.

In order to catch up with the massive backlog of chemical compounds that need toxicity assessments, the NIH, EPA, and FDA are expanding their Tox21 robot screening program to start testing a compound library of 10,000 samples. The Tox21 screening program was first conceived in 2005 and is a joint development between these three agencies. The Tox21 robot, located in Rockville, MD, was introduced earlier this year as the heart of the program and has already studied about 500 chemicals. To give you an idea of what an improvement this is, the EPA has only tested 200 chemicals since 1976. By speeding up chemical toxicity analysis the government will also accelerate the drug development process, as drug toxicity is one of the primary reasons new drugs fail.

The six-ton Tox21 robot system can test thousands of chemicals simultaneously using its vast network of tiny wells to perform high-throughput, cell-based assays at 15 different concentrations. The robot system is able to identify which chemicals have a potentially harmful reaction and then isolate them for further analysis by researchers. The economies of scale provided by Tox21 allow the program to keep the cost of testing each chemical to only a few hundred dollars.

The types of chemical compounds being tested by Tox21 are the same ones that go into food additives, medication, and industrial solvents, so the stakes for this project are high. To this end, the Tox21 team has opted for full disclosure of its results. From the Tox21 website you can see the full results of the chemicals that have already been tested, as well as the list of the 10,000 chemicals scheduled for analysis.

An added benefit of this project is that one of its mandates is to look for new chemical testing strategies that will minimize the number of laboratory animals used.

Learn more about Tox21 here.
Read the press release from NIH here.