Can Microarrays Accelerate Influenza Diagnosis?

A microarray -- a leading-edge molecular biology tool containing influenza DNA sequence information -- developed by researchers at the University of Colorado, Boulder, and recently tested by the Centers for Disease Control and Prevention, has shown that it can identify specific types and subtypes of influenza strains from patient samples in less than half a day.

This is not the first influenza-targeting diagnosing microarray, and it is not likely to be the last as the specter of an influenza pandemic hovers over global public health. Last month, Mulkiteo, Wash.-based CombiMatrix announced the availability of a commercial microarray for the identification of H5N1 bird flu virus and, the company said, all other strains of Influenza A.

Both so-called "chips" shorten current methods that take can days to characterize flu subtypes infecting patients, and animals. Still, today both are limited to use in labs with the sophisticated equipment necessary to process the chip, which in the University of Colorado case, is a very high quality microscope slide spotted with DNA. The CombiMatrix chip is based on the company's semiconductor technology.

The Colorado chip, developed in the lab of Kathy Rowlen, a chemistry professor, was evaluated for three primary subtypes of flu in the October CDC test -- the avian flu strain H5N1, and two of the most common human flu types worldwide in recent winters, H1N1 and H3N2.

The chip was more than 90 percent accurate and will be tested again for accuracy and speed against standard flu-virus culturing methods at the CDC's Atlanta headquarters next month, the university said in a statement. The university researchers are planning to make the sequence information, derived from the Las Alamos National Lab influenza database [subscription required], freely available to researchers.

The Colorado technology was developed with a $2 million, five-year grant to CU from the National Institute for Allergies and Infectious Diseases. Dr. Rowlen's lab is also working on technology that would free the technology from the lab bench.

“In theory, you want to try to get rid of all the work in labs with sophisticated equipment to catch and preconcentrate the virus,” Martin Mehlmann, a post-doctoral researcher in Rowlen's lab, told New Biology Economy. “The idea is to have a small device with a power supply that could be used [in the field]. There is a still a long way to go.”