Prior to their breakthrough research, doctors thought that the life threatening flare-ups of COPD were caused by bacteria in a person's lungs reaching a critical mass, causing increased shortness of breath and production of thick, airway-clogging mucous.
The two UB scientists proved the bacterial-load theory wrong when they made the key discovery that these flare-ups are not the result of an increase in the number of bacteria, but instead are due to new strains of bacteria that COPD patients continuously acquire.
In 2002, they published their findings in the New England Journal of Medicine in what is now considered a landmark paper in the field.
In subsequent studies, Murphy and Sethi showed that when COPD patients acquire new strains of bacteria they have an inflammatory response much greater than with a previous strain.
They also made a related, critical discovery that showed how immunity to these bacteria is strain specific, a finding that explained why patients remain susceptible to the exacerbations.
This discovery is crucial because it enables researchers to identify genes or key molecules in the strains that can be targeted by vaccines or other therapies.
Today they continue to lead the longest-running clinical investigation of COPD in the United States.
Researchers worldwide seek out their biorepository of clinical samples, looking for clues that can be teased out of the bacterial strains, serum and sputum they have gathered and stored for more than two decades.