The researchers found that injecting the C. pneumoniae peptides into mice provokes heart inflammation, caused by T cells infiltrating the heart muscle. In addition, when T cells from an injected mouse were transferred to another mouse, they caused the same heart-destroying response in the second animal. Scientists need to sort out whether the inflammation is indeed caused by the immune response and not simply by the microbe. If it is caused directly by the microbe, then antibiotics might be useful. Creating a vaccine against C. pneumoniae , however, would be risky because the vaccine could inadvertently trigger the immune system that caused heart disease.
Heart disease is merely the latest common affliction thought to be partly caused by the bacterium.
Researchers at the Philadelphia College of Osteopathic Medicine have found signs of the microbe in 27 of 29 autopsied brains of people with Alzheimer's disease, but in only one of 19 brains from non-Alzheimer's patients. Other chronic ailments that are suspected to have microbiological roots are gallstones and kidney stones, juvenile rheumatoid arthritis, scleroderma, and cerebral palsy. Perhaps the most significant revelation in microbe-caused diseases was the common ulcer, which is now known to be caused by the bacterium Helicobacter pylori .