Canadian team's portable device could ease HIV/AIDS monitoring

Rakesh Nayyar (L) flow cytometry expert, University of Toronto PhD candidate Jam

Canadian researchers have invented a device that could make it easier, faster and cheaper to track the progression of HIV in patients living in the developing world.

A team led by University of Toronto student James Dou; Stewart Aitchison, Dou's research adviser; and researcher Rakesh Nayyar from Toronto's University Health Network has created a portable device that uses a computer chip with software capable of analyzing blood tests outside the lab.

The team's portable cell analyzer makes it possible for health-care workers to monitor HIV patients in remote areas by testing their blood on the spot and receiving results within minutes, Nayyar explained.

"There (are) tonnes of stories out there with people that have to walk half a day to a clinic to get blood, and that sample gets taken by bicycle or by truck to a bigger urban centre," Nayyar said. "And then they've got hundreds of tests, so they don't get to the tests for days. You don't get results (because) to disseminate the data takes a long time. It's just a cumbersome thing."

But with the research team's portable cell analyzer, the test can come to the patient and be administered by a nurse instead of a specialist, said Dou, a 33-year-old PhD candidate in engineering.

An HIV patient's blood is tested to determine whether or not the patient currently needs antiretroviral medication, Nayyar said. The patient's status can change over time, making it necessary for health-care workers to routinely test patients' blood.

Most machines currently performing flow cytometry, the technique used to analyze patients' blood for a range of disease markers, including those used to test HIV patients. They are often the size of a photocopier and cost upwards of $100,000, with the cost of each blood test ranging from $75 to $100, Nayyar said.

The portable cell analyzer works a bit like the glucometers used to test diabetes patients' blood, Dou explained.

A nurse would prick the HIV patient's finger and draw a sample of blood into a channel on a test chip, Nayyar said. A few minutes later, the chip would go into the portable cell analyzer, where it would be tested, with results ready in minutes. The devices would cost about $5,000 to $10,000 each, with each test costing only a few dollars to process.

The team is working to make the next prototype capable of sending results wirelessly to a medical database, making it easier for doctors to keep track of patients in remote areas, Dou said.

They're also scaling down their current prototype — a creation about the size of a loaf of bread that looks like a microscope — to fit in one hand, Dou said. The new prototype should be a bit bigger than a smartphone and even have some similar capabilities, such as a camera, GPS and wireless communication.

Their goal is to have the hand-held version ready by March in hopes of sending up to 100 portable cell analyzers to Malawi and Thailand for use in the field by mid-2012, Dou said.

According to the UN's 2010 report on AIDS, about 22.5 million people in subSaharan Africa are living with HIV. Another 4.1 million people are living with the virus in South and Southeast Asia.

The research team has joined with Dignitas International, a Toronto-based HIV and AIDS organization, and with the Camillian Social Center in Thailand to bring the analyzers to HIV patients abroad.

A cheaper, more durable machine to monitor HIV patients would be welcome for patients around the globe as long as it's accurate, said Dr. Richard Harrigan, the director of the laboratory program for the B.C. Centre for Excellence in HIV/AIDS.

"Right now, the costs and the logistical hurdles involved in measuring how well HIV treatment is working for an individual mean that in most parts of Africa and other resource-limited settings, there is no individual monitoring of therapy," the expert in flow cytometry wrote in an email to Postmedia News. "This differs from the West, where we test individuals on an ongoing basis to see how their virus is being affected by the drugs and how their immune system is responding."

Dr. Janet Gilmour from the University of Calgary's Faculty of Medicine just returned from a month-long trip working in rural Malawi.

Treatment in Malawai is even further behind other countries in sub-Saharan Africa, said Dr. Gilmour, who has also worked in Nigeria and South Africa.

In Canada, patients are tested once ever three to four months, she said. Ideally, patients in Africa would be tested at least once a year, if not once every six months. Right now, patients in Malawi are often given drugs without any way to monitor their progress.

"If they had something that could give them (these tests) would really go a long way to allowing the people providing care to improve the quality of care they could provide, even within their limited resources," she said.

But a cheaper device alone won't solve the problem of accurately monitoring HIV patients in Africa, Harrigan wrote.

"There are a lot of complications, like the ongoing costs of testing, and infrastructure requirements for consistent refrigeration for the supplies, good power, an ability to service instruments in remote locations and so on," he wrote. "So I don't think that merely having the machine itself cost (one-tenth) as much is a 'game-changer' for the poorest countries, but could be quite useful for places like Thailand."

The cost savings and portability could make the portable cell analyzer useful in Canada, Dou said. In particular, Dou said he could see it being used in the North and on remote aboriginal reserves.

If the portable cell analyzer works well in Malawi and Thailand, the team will apply for approval in Canada and the United States, Nayyar said.

The process of inventing the portable cell analyzer began in 2007 when Dou, then one of Aitchison's master's students, was developing lab-on-a-chip technology. Dou and Aitchison were looking for a practical use for their chips when they met Nayyar, an expert in flow cytometry, Dou said.

While Dou and Aitchison brought an expertise in engineering to project, Nayyar brought the biology know-how.

Nayyar said he was inspired by Canadian AIDS activist Stephen Lewis to improve care for HIV patients in the developing world.

Dou was looking to use his lab-on-a-chip for complicated cancer diagnostic tests, but Nayyar said he convinced Duo to use the technology for simpler HIV progression tests because there was a need for such tests to be made portable and the idea was more doable than diagnosing cancer.

In the four years since, the team has set up a company called ChipCare Corp. through a University of Toronto program that helps students commercialize their research projects, Dou said.

Funding remains a challenge.

To make 100 portable cell analyzers for Malawi and Thailand, the team needs an additional $3 million, Nayyar said.

HIV patients are just the first ones who may benefit from the portable cell analyzer, Dou said. Malaria and white blood cell count tests are the next step. Testing for tuberculosis and food-borne infections would come after.

 

Author: 
Hilary Roberts, Postmedia News
Photo: 
Jennifer Roberts, for Postmedia News
Source: 
www.vancouversun.com/health/Canadian+team+portable+device+could+ease+AIDS+monitoring/5847655/story.html
Published: 
12 December 2011