Scientists are exploring new therapies targeting human cells rather than bacterial cells to treat bacterial pneumonia to overcome the limitations of existing antibiotics. The latest mice model research has been successful in treating bacterial pneumonia involving white blood cells of the immune system called macrophages that eat bacteria, and a group of compounds that are naturally produced in mice and humans called epoxyeicosatrienoic acids or EETs. Currently, the antibiotics-based treatment in severe lung infection is not always successful, and in some cases, the bacteria become resistant as well. The new research led by Dr. Matthew Edin, a scientist at the National Institute of Environmental Health Sciences (NIEHS), part of NIH, wanted to find a way to augment the body’s immune system to resolve the infection. 

The team found that bacterial infection induces a protein called soluble epoxide hydrolase (sEH) that degrades EETs. In contrast, when sEH is blocked, EET levels skyrocket, hampering the macrophages’ ability to sense and eat bacteria. As a result, the bacteria continue to reproduce in the lung, which leads to severe lung infection and death. However, the new research found a way to get macrophages to eat more bacteria, that is to decrease the ability of EETs to do what they normally do, which in turn limits inflammation. The research was published in the Journal of Clinical Investigation