Carbon monoxide (CO) is a gas most of us associate with accidental poisoning. CO is produced by partially combusted fossil fuels. When large amounts of CO are inhaled for long periods of time serious problems and death may occur. Carbon monoxide is an important and naturally occurring compound which is necessary for our immune system to function properly.

There are specialized cells in our bodies call macrophages. These cells are part of our immune system and they locate and “eat” bacteria and other compounds which may be harmful to us. Carbon monoxide is produced inside our macrophages and the levels are especially high when they are fighting bacteria. When the ability of our cells to produce CO becomes impaired, they are much more sensitive to the effects of the bacteria and we become much sicker.

There is a two-step process involving carbon monoxide and our macrophages in fighting off bacteria. Here is how it works. Our macrophages send out carbon monoxide signals. When these molecular signals encounter bacteria, they bind to it and force the bacteria to send out its own chemical signals, which bind to the macrophage. In this process the macrophage is alerted to the presence of bacteria and begins to attack it. It also sends out signals that call other macrophages and other white cells to come and help with the attack. If we prevent the formation of carbon monoxide in our macrophages we run the risk of serious uncontrollable infections.