The findings were published by PLOS-ONE, an international, peer-reviewed online publication.
The paper notes that Borrelia burgdorferi, the causative agent of Lyme disease, is continuously rearranging its structure. It can transform itself from motile spirochetes into cystic, granular or cell wall deficient forms even when it is in an unfavorable environment.
To do this, the Borrelia forms a biofilm – a slimy substance that often forms on surfaces that are in contact with water. Biofilms consist of bacteria and other microorganisms. In the case of Lyme disease, the biofilm allows the bacteria to “hide” until the environment is favorable again, the paper concludes. The bacteria can then reappear, Sapi said.
“We have found substantial evidence that Borrelia burgdorferi is capable of forming biofilm,” Sapi said. “Biofilm formation might play an important role in how well this bacterium survives inside a tick or a mammal, including a human. The research shows it survives in diverse environmental conditions by providing refuge to individual cells.”
Sapi said the formation of biofilm allows the Borrelia to hide and remain dormant for periods of time.
The research on this paper was done in vitro – that is, in a test tube. The next step will be doing research on the bacteria in tick samples and infected mouse and human tissues to see if the biofilm formation helps Borrelia to survive and spread in the different tissues, Sapi said.
Her previous research showed that aggregates of Borrelia are very resistant to the antibiotics commonly used for Lyme disease treatment. The new research showed that those aggregates are indeed true biofilms, which are well-documented as resistant to unfavorable conditions and to antibiotics.
Sapi was a cancer researcher at Yale University when she joined the UNH faculty in 2001. The following summer, Sapi became ill with a strange malady. She suffered from insomnia and her motor skills were impaired. Constantly dizzy, she experienced chronic nausea.
“I went through several months of medical tests,” she said, “but they were all inconclusive.”
Finally, in desperation, she underwent magnetic resonance imaging. Physicians still couldn’t offer a definitive diagnosis, but they told her she might have Lyme disease.
“I didn’t know anything about Lyme disease,” said Sapi, who grew up in Hungary and earned her Ph.D. in genetics at Eotvos Lorand University in Budapest before coming to the United States for postdoctoral training in molecular biology at the Yale University’s School of Medicine.
She began studying the disease with characteristic intensity. Eventually she found a physician who prescribed a regimen of anti-microbial drugs that provided relief. By then, Sapi had learned enough about Lyme disease to know she wanted to know more.
Eight years ago, she abandoned her research on ovarian cancer and turned her attention to the most prevalent tick-borne illness in the nation.
Lyme disease is caused by a spirochete called Borrelia burgdorferi, a bacterium carried by the tiny deer tick. First discovered in Connecticut in 1975, it has spread widely as the white-tailed deer population has exploded and it has become an expensive public health problem.
“Lyme disease costs the U.S. about a billion dollars a year, including inappropriate medical care, lost productivity and legal fees associated with misdiagnosis,” said Sapi.