Transforming the Terrain of TB Diagnosis
Tuberculosis is one of the most significant public health challenges in India. We all remember Amitabh Bachchan in that advertisement rebuking a man who claims that he just has a regular cough to go to the hospital and get a checkup. But the issues don’t end there. The actual diagnosis of the disease is often problematic–owing to limited resources in countries like India and long diagnostic waiting times. Unsurprisingly, only 58% of the infected people are appropriately diagnosed and treated and around 10 lakh people are suspected to be undiagnosed in India.
A team of scientists, led by Dr Ravikrishnan Elangovan (Department of Biotechnology, IITD), Dr Seyed E Hasnain (Kusuma School of Biological Sciences, IITD & VC, Jamia Hamdard University) and Dr Nasreen Ehtesham, (Deputy Director, National Institute of Pathology), are tackling this issue by designing an cost-effective and automated system for the diagnosis of Mycobacterium Tuberculosis.
How does MTB diagnosis currently work?
Currently, diagnosis of pulmonary TB is performed by confirming the presence of Mycobacterium tuberculosis (MTB) in sputum samples. The existing methods for detecting MTB in sputum include smear testing (microscopy), liquid culture and many different NAAT (Nucleic Acid Amplification Test) systems (e.g., GeneXpert). However, these methods require expertise in handling and are riddled with other problems. Smear testing, the most prevalent method, lacks the necessary sensitivity of detection which can result in incorrect diagnosis. These also require a certain level of expertise in handling and some fall behind where the time taken for diagnosis and affordability are concerned.
The iMC2-TB System
The researchers have developed a field-deployable and rapid MTB diagnostics test-system called the ‘iMC2 TB (Immuno-Magnetic Cell Capture Tuberculosis) test’. The process involves on-site collection of a patient’s sputum sample, followed by thinning, immunomagnetic enrichment and confirmation using an inbuilt fluorescent detector.
Before we lose you in the details, let’s first take a look at what makes this system special–
- Ease of operation: The iMC2-TB system is self-sustainable and does not require any existing lab setup. Healthcare personnel trained in for basic errands in healthcare centers can use the device due to its design.
- Time: The device confirms the detection of MTB cells in only 1 hr.
- Safety: The whole process is performed in a closed system to avoid exposure to health-workers.
- Power Efficiency: Since this device requires minimum power to run the sample, battery operated devices can be deployed in the primary healthcare centers where power cuts are frequent. This also makes the device apt for the resource limited settings one is likely to encounter in developing countries.
- Affordability: The device is anticipated to cost only between Rs 300-500
The device comprises of a disposable capture chip that has two chambers of 5 ml and 50 μl volume connected through a channel with a manual valve. Bacterial cells bound to antibody-coated magnetic nanoparticles are swept from the 5 ml sample chamber into the 50 μl recovery chamber by moving an external magnetic field with respect to the capture chip. This enables specific isolation and up to 100× enrichment of the target cells. The presence of bacteria in the recovered sample is confirmed visually using a lateral flow immunoassay (a procedure for detecting or measuring specific proteins or other substances through their properties as antigens or antibodies).
The Road Ahead
A patent has been filed for the device, which is now undergoing clinical trials and has transcended the boundaries of the laboratory. Post trials the project is expected to scaleup for commercial scale manufacturing.
The researchers along with IIT Delhi graduates Saurabh Singh and Vikas Pandey have also co-founded a startup–Valetude Primus which was incubated in IIT Delhi. Incidentally, the startup–which has won the Pfizer innovation grant and recently, the Gates Grand Challenge Award–has also produced a gadget for Typhoid detection using very similar technology. They have now patented this technology and have transferred this to the startup.
The project was undertaken as part of the IMPRINT programme; an MHRD supported Pan-IIT + IISc initiative to address major science and engineering challenges of the country. The IMPRINT programme, which stands for IMPacting Research INnovation and Technology, aims to provide the overarching vision that guides research into areas that are predominantly socially relevant and serve as a bridge to link research going on in the premier institutes of the country to the lives of the masses.
Many other efforts are also made by various other researchers in IIT Delhi to counter problems faced by our nation. It not only lends a special meaning and significance to science but also inspires many young minds to pursue it. The business potential of this research provides another incentive to young researchers. A special thanks to Prof. Ravikrishnan Elangovan for his contribution to the article. We wish the entire research team the very best in their future endeavors. We also take this opportunity to applaud the efforts made by the institute and the government to promote research.