Opening a Window Into Lyme

Lyme disease is a worrisome condition for both pa-tients and clinicians. Patients have questions about symptoms, diagnosis, and the meaning of chronic Lyme disease. In laboratories, Borrelia burgdorferi is hard to culture, limiting our understanding of disease progression postinfection as well as interfering with our diagnostic abilities. “Current tests for Lyme are good tests, ” says Elitza Theel, Director of Infectious Diseases Serology Labora-tory atMayo Clinic. But “they canmiss initial infection.” The problem, Theel explains, is that these tests look for antibodies; if the patient presents early in disease—say the first 2–4 weeks—the current tests can miss infection. Therefore, developing a new Lyme diagnostic that could catch disease earlier would be a powerful tool, not only for diagnosis, but also for understanding dis-ease progression. Past attempts to tackle these problems have focused on tests that optimize cell culture, says Theel, but since Borrelia burgdorferi is hard to grow and does not cause a huge bloodstream infection as bacteria do, these tools have not caught on. “PCR methods have been looked at, but sensitivity isn’t strong because the organism doesn’t reach a high enough concentration to become detect-able, ” she says. Next-generation sequencing andmicroar-ray, with greater sensitiv-ity for DNA and RNA, are currently in early stages of development for Lyme disease, says Theel. In this article, we fo-cus on a third approach: a new class of tiny chemi-cal biosensors that test directly for the bacteria itself, using standard anti-body chemistry and car-bon nanotubes for mea-suring charge changes. What Is the Innovation? “Detecting chemicals in medical diagnostics, or even out in environ-ment, is something we are not very good at,