Lab-on-a-chip delivers critical immunity data for vulnerable populations

April 25, 2018, University of Toronto
The reconfigurable lab-on-a-chip platform, dubbed the MR Box. Credit: Wheeler Lab

For millions of displaced people around the world—many of them refugees, living in temporary shelters under crowded conditions—an outbreak of disease is devastating. Each year, the measles virus kills more than 134,000 people globally, and another 100,000 children are born with defects caused by congenital rubella syndrome. Both diseases are preventable by vaccination.

Now, a team of researchers from the University of Toronto has applied a hacker mentality to developing a portable, reconfigurable diagnostic platform and field-tested the system in remote Kenya. Their validated platform can gauge the level of immunity to vaccine-preventable diseases among vulnerable populations. Their work appears today in the journal Science Translational Medicine.

"We found that our low-cost device matched the international laboratory-standard reference tests of the Kenyan Medical Research Institute for 86 per cent of measles samples, and 91 per cent of rubella samples," says Darius Rackus, one of the lead authors of the paper.

These results underscore their platform's potential to help identify populations susceptible to epidemics in remote or under-resourced locations.

"Our platform is inexpensive, fast and flexible—there's nothing like it out there," says Rackus. "We see it as a powerful tool for on the front lines, who have no access to health records, or may be dealing with humanitarian emergencies."

From left: Christian Fobel, Alphonsus Ng and Julian Lamanna run blood tests on their MR Box instruments in their temporary lab at the Kakuma refugee camp in Kenya. Credit: Ryan Fobel

Rackus and his team, led by Professor Aaron Wheeler, are world leaders in the area of digital microfluidics, a technique used to move, split, recombine and mix miniscule droplets of liquid all on a tiny 'chip.' The chips are made using low-cost fabrication techniques such as ink-jet and 3D printing, and the droplets are controlled by applying electrical signals to different electrodes.

In June 2016 four members of the Wheeler Lab travelled to the Kakuma refugee camp in northwestern Kenya to validate their platform, dubbed the MR Box—a desktop lab the size of a toaster oven configured to test for measles and rubella.

They arrived in Kakuma following a massive public-health immunization campaign and tested hundreds of children and their caregivers for the presence of molecular markers indicating immunity. They then sent their samples to the Kenyan Medical Research Institute national laboratory in Nairobi for validation.

The Wheeler Lab researchers prepare to leave Kakuma in June 2016. Credit: Ryan Fobel

"For the first time taking digital microfluidics out of the lab, this is phenomenal result," says Julian Lamanna, one of the paper's authors and a member of the team who was on the ground in Kakuma. "In future, with simple statistical analyses our point-of-care system could be used to monitor the levels of immunity within dynamic populations, helping prevent outbreaks before they happen."

"If you could distribute these devices at airports or points of entry around the world, they could become a powerful tool for disease surveillance and monitoring," adds Rackus. "They also have the potential to significantly reduce the burden on expensive and sophisticated diagnostic labs that currently do all these epidemiological tests."

Since the trip to Kakuma, the team has taken MR Boxes for additional testing in the Democratic Republic of the Congo. They are also developing new chips to test for different markers and diseases, including zika and malaria.

"What we've demonstrated is a universal platform—our microfluidic chips are relatively generic, and highly customizable," says Wheeler. "Now that we've seen how practical it is in the field, we want to adapt it to as many diseases and environmental conditions as we can."

Explore further: Science Says: Why Europe still has so many measles outbreaks

More information: A.H.C. Ng el al., "A digital microfluidic system for serological immunoassays in remote settings," Science Translational Medicine (2018). stm.sciencemag.org/lookup/doi/ … scitranslmed.aar6076

Related Stories

Science Says: Why Europe still has so many measles outbreaks

March 2, 2018
While parts of the world have all but banished measles, Europe is still getting hit with large outbreaks where some people don't get vaccinated.

New technology for diagnosing immunity to Ebola

January 15, 2018
A promising new approach to detect immunity to Ebola virus infection has been developed by researchers from i-sense in a collaboration between UCL and Imperial College London.

Large percentage of youth with HIV may lack immunity to measles, mumps, rubella

August 13, 2015
Between one-third and one-half of individuals in the United States who were infected with HIV around the time of birth may not have sufficient immunity to ward off measles, mumps, and rubella—even though they may have been ...

More attention to measles, vaccine experts urge

October 29, 2014
Doctors and public health authorities need to renew their attention to measles, researchers from Emory Vaccine Center urge in an editorial in the New England Journal of Medicine.

Tanzania launches giant measles vaccination drive

October 19, 2014
Tanzania on Saturday launched its biggest ever campaign against measles and rubella aimed protecting 21 million children from the potentially fatal diseases.

Lack of immunity poses greater threats as children grow older, according to study

June 8, 2015
Before vaccines, a kid didn't have to wait very long before catching diseases like the measles. Now that most people are protected against those former childhood killers, an unvaccinated person could go years or even decades ...

Recommended for you

Fetal gene therapy prevents fatal neurodegenerative disease

July 16, 2018
A fatal neurodegenerative condition known as Gaucher disease can be prevented in mice following fetal gene therapy, finds a new study led by UCL, the KK Women's and Children's Hospital and National University Health System ...

New study finds that fat consumption is the only cause of weight gain

July 13, 2018
Scientists from the University of Aberdeen and the Chinese Academy of Sciences have undertaken the largest study of its kind looking at what components of diet—fat, carbohydrates or protein—caused mice to gain weight.

Basic research in fruit flies leads to potential drug for diseases afflicting millions

July 13, 2018
River blindness and elephantiasis are debilitating diseases caused by parasitic worms that infect as many as 150 million people worldwide. They are among the "neglected tropical diseases" for which better treatments are desperately ...

Light based cochlear implant restores hearing in gerbils

July 12, 2018
A team of researchers with members from a variety of institutions across Germany has developed a new type of cochlear implant—one based on light. In their paper published in the journal Science Translational Medicine, the ...

Researchers discover gene that controls bone-to-fat ratio in bone marrow

July 12, 2018
In an unexpected discovery, UCLA researchers have found that a gene previously known to control human metabolism also controls the equilibrium of bone and fat in bone marrow as well as how an adult stem cell expresses its ...

Intensive care patients' muscles unable to use fats for energy

July 12, 2018
The muscles of people in intensive care are less able to use fats for energy, contributing to extensive loss of muscle mass, finds a new study co-led by UCL, King's College London and Guy's and St Thomas' NHS Foundation Trust.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.