Studying these cells could lead to new treatments for diseases ranging from gastrointestinal disease to diabetes.
One of the biggest challenges in fighting tuberculosis is simply getting patients to take their medicine.
MIT students have come up with a possible solution: A new testing and reporting system that is easy for patients to use and offers economic incentives such as free cell phone minutes.
Tuberculosis kills an estimated two million people every year, and treating the disease requires a strict six-month regimen of antibiotics. If patients abandon the treatment early, the TB bacteria survive and can become resistant to first-line antibiotics.
"TB is a massive problem, and it's exacerbated by the fact that people have a lot of trouble staying on their meds," says Elizabeth Leshen, an MIT sophomore majoring in biological engineering and member of the team, known as "X Out TB."
The students' plan, which has been field-tested in Nicaragua, combines a newly developed paper testing strip with a simple text message reporting system to ensure drug compliance.
The team's novel test strip takes advantage of new technology known as paper microfluidics. The strip is embedded with chemicals that react with metabolites present in the urine of patients who have taken TB medicine. When the chemical reaction occurs, the strip changes color, revealing a number.
Patients are given a device that dispenses one strip every 24 hours, and after they successfully take the test, they have about two hours to text the number on the strip to a central database that records that they have taken the drug.
Patients whose compliance rate is high enough receive free cell phone minutes. The team decided on cell phone minutes as an incentive because it's fairly easy to set up the reward system, and because most of the target patients have a cell phone already.
"It's really easy to tell cell phone companies to give someone extra cell minutes. You don't need a new infrastructure," says Leshen, who joined the team last fall.
Susan Murcott, who teaches D-Lab III: Dissemination, is advising the team. She says she's impressed with the innovation shown by the students.
"There are a lot of creative elements," said Murcott, a lecturer in civil and environmental engineering. "They've engineered a better urinalysis test, you don't have to send somebody out every day to check that patients are taking their medication, and there are these incentives built into the program."
The new system could be a breakthrough in monitoring patients in developing countries who don't live near medical centers, says Jose Gomez-Marquez, who joined the team while a grad student at Worcester Polytechnic Institute and is now directing MIT's Innovations in International Health initiative.
"Some of these people live six hours from the nearest health care center, so telling them that they have to come in every day to check if they're taking their medication is a non-starter," he said.
Gomez-Marquez, who is from Honduras, also believes the project will transform the relationship between patients and health care workers.
"Their lives are so hard already, and the last thing they need is to become an example of disappointment in another person's eyes," he says. "We're turning that around and rewarding them for doing good."
The project got started as part of the 2006-2007 Muhammad Yunus Innovation Challenge to Alleviate Poverty, which challenged students to find a way to get TB patients to take their medicine. The Yunus Challenge, part of MIT's IDEAS Competition, is sponsored by Mohammed Abdul Latif Jameel, benefactor of MIT's Jameel Poverty Action Lab.
The "X Out TB" team decided that simply reminding people to take their medicine is not enough--the best way to get people to comply is to offer them an incentive. Similar incentive programs have been launched in the United States.
"This is a universal concept that, given the right technology, we think can be applied just as effectively in developing countries as it can here," says Leshen.
The team plans to run larger field tests in Pakistan and Indonesia this summer, in conjunction with local hospitals.
Other members of the team are Minyoung Jang '07, Elizabeth Gillenwater '07, Aron Walker '07, Angela Kilby '07 and Jeffrey Blander, lecturer in the Harvard-MIT Division of Health Sciences and Technology.