Tuberculosis (TB), a bacterial disease that usually attacks the lungs, has regained its distinction as the leading infectious disease resulting in death, following the extraordinary efforts to curb the spread of COVID-19. The bacteria that cause tuberculosis, Mycobacterium tuberculosis, are spread through the air, for example when someone with the disease coughs or sneezes. The disease kills nearly 1.5 million people each year.
Early and widespread detection of TB is crucial to slow its spread and save lives, according to Robert Paulino-Ramírez, M.D., principal investigator at the Institute of Tropical Medicine & Global Health at the Universidad Iberoamericana (UNIBE) in Santo Domingo, Dominican Republic, and chair of the Tropical Medicine/Infectious Disease Virtual Institute in the Education and Research Consortium of the Americas (ERCA) within the Michigan State University College of Osteopathic Medicine (MSUCOM) Institute for Global Health (IGH).
“In the Dominican Republic, the tuberculosis rate is very high,” Dr. Paulino-Ramírez said. “One of the most important gaps in treatment is rapid identification of active cases at the community level.”
To recognize community transmission requires rapid diagnosis, but currently the only way to do that in the Dominican Republic national health care system is through Polymerase Chain Reaction (PCR) testing, a time-consuming and expensive procedure requiring highly trained technicians. “PCR testing is cost-prohibitive and even the reagents required are in short supply due to supply chain issues,” said Dr. Paulino-Ramírez.
A $142,000, two-year grant from the Dominican Ministry of Higher Education, Science and Technology (FONDOCYT) will allow Dr. Paulino-Ramírez, in partnership with Michigan State University, to leverage expertise and new technologies to alleviate that problem.
A crucial part of the solution comes from the Nano-Biosensors Lab of Evangelyn Alocilja, Ph.D., professor in the MSU Department of Biosystems and Agricultural Engineering, and Ruben Kenny Briceno, M.D., IGH Co-Coordinator Peru Research and member of the Nano-Biosensors Lab, who developed a test for TB that uses nanoparticles targeted to specific proteins and genes of the tuberculosis bacteria.
The test is about 30 times cheaper than PCR, requires very little training time for health care personnel and even students, and, unlike the reagents used in PCR testing, can be stored at room temperature, according to Dr. Paulino-Ramírez. “The technology has been demonstrated to perform extremely well in vitro.”
“The nanoparticle-based TB test has been validated in hundreds of sputum samples in Mexico, Peru and Nepal, and the results are comparable to the PCR-based GeneXpert system,” Dr. Alocilja said. “Dr. Paulino-Ramirez and I are excited to work together toward potentially improving TB diagnosis in the Dominican Republic.”
How the body reacts to infection depends greatly on the health of a person’s immune system. Therefore, the team will first confirm the efficacy of the nanoparticle test vs. PCR in a clinical setting for both immune-suppressed and non-immune-suppressed patients. If confirmed to be effective, “the transfer of this technology will be hugely beneficial, especially in middle- and lower-income countries,” Dr. Paulino-Ramírez said. Currently, patients are often treated based on symptoms alone rather than a positive TB test, simply because the cost is too high or the materials are unavailable.
“Without the need for costly molecular biology laboratories and -70°C storage facilities (both are required for PCR), it will be much easier for health care providers at the community level to detect TB.”
Dr. Paulino-Ramírez is excited about the potential of the new technology and its ability to expand disease detection. Because nanoparticles are easy to tailor to specific diseases, Dr. Paulino-Ramírez, Dr. Alocilja, Dr. Briceno and the collaborating team are optimistic that the technology can be adapted in the future to detect other diseases, including coronaviruses.
“The Institute for Global Health and the College of Osteopathic Medicine are privileged to partner with the College of Engineering (COE) and the Tropical Medicine Institute at UNIBE, Dominican Republic, to expand research on early diagnosis of tuberculosis and other infectious diseases through nanotechnology. Dr. Briceno de la Cruz from IGH, Dr. Alocilja from COE, and Dr. Robert Paulino, main researcher at the Tropical Medicine Institute, will lead the next phase of this project in the Dominican Republic," said William Cunningham D.O., MHA, director of IGH and associate dean for Global Health at MSUCOM.
By P. Liu