Since the body's immune response is central to how Pneumocystis kills patients, doctors use two different types of drugs in tandem to treat patients an antibiotic to kill the bug, and steroids or another type of drug to reduce the consequent inflammation.
Central to the study were mice in which the disease progresses in a manner very similar to AIDS patients. The remarkable strides in AIDS therapy in recent years have come with a down side for many patients, thanks to Pneumocystis: When anti-retroviral therapy kicks in, a patient's immune system often becomes stronger very quickly and if the fungus is present, the immune system attacks it vigorously, causing a potentially deadly form of pneumonia.
Wright's team looked at the effects in mice of sulfasalazine, an anti-inflammatory drug that has proven useful in treating conditions like Crohn's disease and rheumatoid arthritis. The team found that Pneumocystis-infected mice treated with sulfasalazine developed much less severe disease than untreated mice. The sulfasalazine-treated mice had better lung function, less weight loss, and were generally healthier than untreated animals.
While some of the benefit was due to the drug's anti-inflammatory properties and was expected, the result included a big surprise: The drug also spurs the body to remove the bug more aggressively by boosting the activity of immune cells called macrophages.
"This was unexpected," said first author Jing Wang, Ph.D., research
|Contact: Tom Rickey|
University of Rochester Medical Center