Jan. 18, 1995
Dr. Mario Pinto could have been an actor. Or a writer. Or a singer. He did all these things well as a youngster and considered careers in each. Even when he attended Queen's University and narrowed his options to science, he tested various fields of science -- mathematics, computer science, life sciences. In his third year, he decided chemistry fitted him best.
Pinto came to Simon Fraser University in 1983 following post-doctoral studies with Sir Derek Barton, winner of the 1969 Nobel Prize in chemistry. "I work at the interface of two fields -- organic chemistry and immunology," he explains "We investigate the forces that control the shape of molecules in order to design improved immuno-diagnostic agents or vaccines."
Pinto compares his research to mapping mountain topography. "I map the topography of the molecules found on the surfaces of potentially harmful bacteria. Then I explore how those molecules -- whether they are carbohydrates, peptides or proteins -- are recognized as distinct by the immune system."
This line of research has enormous implications, especially for auto- immune diseases such as rheumatic heart disease, where the body's own antibodies begin to destroy body tissue. According to Pinto, this involves 'molecular mimicry'. It means that something in the body's tissue resembles the foreign molecules that the antibodies are supposed to attack. As a result the antibodies attack the healthy tissue instead.
Sometimes, when the body produces antibodies against the bacterium that produces strep infection, some of the antibodies will attack heart tissue, causing rheumatic heart disease. Pinto and SFU colleague, Dr. Jamie Scott, a molecular biologist, are attempting to develop vaccines with molecular sites that will fool the errant antibodies into chasing them and forsaking the vulnerable heart tissue.
"There is a whole family of antibodies that recognizes the same carbohydrate molecule on the bacterial surface," explains Pinto, "but each member of the family aims at a different site on that molecule. We've been able to get peptide molecules that can both mimic the different sites on the carbohydrate molecules on streptococcus bacteria and distinguish between different antibodies."
Pinto's research is supported by the Natural Sciences and Engineering Research Council and the Heart and Stroke Foundation of B.C. and the Yukon. He has several consulting contracts with pharmaceutical companies and works with academic and medical research colleagues in Florida, North Carolina, the Bahamas, Sweden, Finland and Denmark.
Graduate students are key players in Pinto's research and they, too, work at the cutting edge of his research projects. A good example is Shannon Harris, now in her fourth year of PhD studies in biological chemistry. Harris is trying to determine what it is about the heart tissue that prompts the antibodies that normally fight streptococcus throat infections to suddenly begin attacking it. "We want to find the molecule in human tissue that mimics the bacterial one and fools the antibodies," she says.
Harris would like to pursue a career in scientific research and teaching at a university. As for how she ended up in science: "I had very good science teachers at my high schools in Nanaimo and Richmond," she recalls. "So when I came to SFU in 1986, I was determined to study something I liked. That was chemistry. I liked chemistry because it helped explain things in the world around me like the meaning of octane in gasoline."
Observes Pinto: "When students come to me, I ask them why they want to do graduate work. I tell them they are going to have to be in the top few per cent if they expect to get a job afterwards. And, believe me, there are good jobs out there for those willing to make the commitment while they are here, I also tell them that they can achieve their academic goals here at SFU. 'We have everything here; all we need is your brain,' I say. Our equipment is state of the art. Computing facilities are top-notch."
Contact: Dr. Mario Pinto, (778) 782-4327, 291-5650 or 291-3590