Jorge Vidal was born and raised in Villahermosa, the capital of the Mexican state of Tabasco, where his father worked as a petroleum engineer. He found his calling, however, in his mother’s nearby hometown. “I spent a lot of time there with my grandmother,” Vidal recalls. “It was a small place in north Tabasco, near the beach, which was fun.”
He also enjoyed hanging around a microbiology lab in the town where his aunt owned a clinical laboratory. “She would culture a blood sample in a petri dish one day and the next day, if the individual had an infection, you could see it colonized on the plate,” Vidal says. “It was fascinating to me to see the organisms that can come out of a body fluid.”
Vidal went on to study chemistry, biology and pharmacy at the University of Puebla, Mexico, before enrolling in a master’s program in microbiology at the National Polytechnic Institute, Mexico’s equivalent of MIT. As a student, he helped provide laboratory training workshops around the country.
Assisting at a lab in Villahermosa while a student affected him deeply. “In one case, a man was infected with flesh-eating bacteria on his back,” Vidal says. “When I collected the specimens, I actually touched the bone in his back. It was really dramatic.”
The man was taking antibiotics, but the infection was resistant to them. “We ran the microbiological analyses needed to figure out which antibiotics would work on the infection, and he was cured, although he lost a large portion of his back,” Vidal says.
Such experiences propelled Vidal to pursue a PhD in cellular microbiology at the Center for Research and Advanced Studies in Mexico City.
In developing countries, Vidal notes, it’s less common for students to pursue a PhD due to economics and smaller scholarships and stipends. “If you know what your skills are and you believe that you can make a bigger contribution if you keep developing those skills and learning, it becomes easier,” he says. “Before committing to a PhD, you have to know that it’s your vocation, that you have a talent for it, and that learning, investigating and training young scientists is something you want to do for your whole life.”
Throughout his successful career, Vidal has continued to mentor students as young as high schoolers in his lab and to provide training in the latest techniques and research for scientists from around the world, including those in his hometown of Villahermosa.
Explaining his science to students, Vidal says, also benefits him. “They make me think about my research in a different way,” he explains. “By making my science simple enough for others to understand, I start to think about how to also simplify the science itself and focus on basic, key questions.”
As an associate professor at Rollins School of Public Health, Vidal began working on Streptococcus pneumoniae, or pneumococcus — a bacteria that can cause ear and sinus infections as well as life-threatening cases of pneumonia, meningitis and bacteremia. Pneumococcal diseases are among the biggest killers worldwide, especially of children.
For decades, a bile solubility test has been used to determine if someone carries S. pneumoniae. First a specimen from a nasal swab is placed in a petri dish and allowed to grow any bacteria it contains. Then sodium desocholate (DocNa), the sodium salt of deoxycholic acid is added. DocNa bursts the cell membranes of S. pneumoniae while leaving similar, harmless bacteria intact. If a bacterial colony dies in the petri dish, that indicates the presence of S. pneumoniae.
This superpower of DocNa, to selectively target and kill harmful bacteria, “rang a bell for me,” Vidal recalls. He began to wonder if DocNa, a bile salt naturally produced by intestinal bacteria that aids in digestion, could work not just to test for S. pneumoniae but to treat the diseases it causes.
“Many scientists are focused on finding new chemicals for drugs and are not so easily convinced about the power of a substance that’s already naturally produced by your body,” he says. “I look at it from the other way around. Humans naturally produce a molecule that kills a major pathogen. To me, innovation is using a new approach to reach an important goal. My goal in this case is safely killing a bug that’s killing people.”
Emory’s Office of Technology Transfer is applying for a provisional patent for this novel medical application for DocNa as Vidal and his colleagues continue studies to characterize the mechanisms underlying its power to kill S. pneumoniae. So far, the results are promising.
Vidal has this advice for other researchers: Try to keep it simple and don’t overlook the obvious.
“Ever since I asked myself, ‘Why don’t we use this naturally occurring bile salt not just to diagnose but to treat?’ it’s been a chain reaction of positive results,” he says. “Consider what happened with the discovery of antibiotics. Who would have thought that the byproduct of a fungi would save so many lives?”