PORTLAND, Ore. Avian flu chips validated by the U.S. Centers for Disease Control and Prevention (CDC) could soon be showing up at U.S. medical clinics.
The "MChip," a microarray which can quickly identify avian flu, will be used to monitor a possible pandemic. It could also be used to streamline clinical laboratory testing. Quidel Corp. (San Diego) holds an exclusive license to manufacture and distribute avian influenza test kits using the patented MChip.
"Quidel's test kits will use a new and improved version of our original flu chip, which we call the MChip," said Kathy Rowlen, project leader for a University of Colorado research team. "The MChip uses very clever bioinformatics to require only a single gene, making it is a substantial improvement over our first version of the chip."
|University of Colorado professor Kathy Rowlen shows its flu chip jointly patented with the CDC.
Flu chips use microarrays containing thousands of DNA protein sequences, each with a fluorescent marker that glows when a match is found. By exposing the entire chip to a patient sample, the microarray can simultaneously test for matches with all its sequences, reducing testing time from days to minutes. The National Instittutes of Health is making a conventional microarray for influenza testing under its Consortium for Functional Glycomics project.
Developers claim the MChip is an improvement over traditional influenza microarrays by requiring a match with only a single avian flu gene. Rival mircoarrays require matching sequences from all three influenza geneshemagglutinin, neuraminidase and the matrix.
The MChip requires only matching sequences from the matrix gene, which mutates more slowly than hemagglutinin and neuraminidase genes, thereby improving reliability as well as shortening testing time.
Conventional influenza microarrays "require literally thousands of sequences, making them comparitively expensive," said Rowlen. "But the MChip is substantially smaller than a conventional microarray since it only needs 15 sequences from a single gene to reliably identify avian flu."
The MChip was jointly developed by the University of Colorado and the CDC, which are co-owners of the original patent. The CDC validated the MChip by testing it with samples of avian flu (called H5N1) collected from both humans and animals over three years. The CDC said the MChip achieved 100 percent specificity, with no reported false positives and a 97 percent sensitivity in identifying avian flu.
Quidel will use its exclusive license to integrate the MChip into its existing line of immunoassay tests for flu, which are used both in clinical laboratories and at doctors' offices.