SLU professor discovers new biomarkers for chlorine gas exposure

Apr 19 2018

As experts sort through questions around recent chemical attacks in Syria, future answers to quickly testing and treating those who may have been exposed to chlorine gas may lie in chlorinated lipids, says a Saint Louis University professor.

After chemical weapons attacks, doctors must quickly try to determine which chemical agent was used so that appropriate countermeasures can be employed to try to save lives and limit damage to those exposed.

Between 2002 and 2006, David Ford, Ph.D., professor of biochemistry and molecular biology at Saint Louis University, made a discovery of a family of lipids that had not previously been identified in humans.

"My lab discovered chlorinated lipids," Ford said. "They are made in the body under conditions where there is inflammation, such as sepsis. They are made as a result of white blood cells executing chlorination reactions to kill bacteria. These lipids are also the best biomarkers of chlorine gas exposure that are available."

Chlorine gas exposure initially causes severe lung injury, followed by hypotension and multiple organ failure.

"The production of these chlorinated lipids has been compared to various stages of fire," Ford said. "A small amount of inflammation in a healthy person is like striking a match with a small increase in the production of these lipids. Sepsis is 20 to 50-fold greater than that, like a bonfire. And exposure to chlorine gas is like a bomb has gone off in the body, causing over 1000-fold more chlorinated lipid compared to no exposure."

Over the past five years, Ford's work has been funded in part through the CounterACT network, a collaborative effort of the National Institutes of Health and the U.S. Department of Defense, which has awarded multiple grants via a collaboration with Sadis Matalon, Ph.D., and Rakesh Patel, Ph.D., at the University of Alabama at Birmingham (UAB).

This research examines how halogen gases like chlorine damage the lungs and other organs with the aim of developing countermeasures that could be given after exposure to save lives and limit the devastating damage to the body caused by chlorine gas.

Among other findings, Ford and his collaborators learned that they could discover exposure to chlorine gas by detecting the presence of reaction products of chlorine. In a 2016 paper, Ford reported that chlorinated lipids remain high even 24 hours after exposure, long after other biomarkers have returned to normal levels.

Testing for chlorinated lipids currently requires a mass spectrometer, which isn't conducive to quick testing in the field. As research continues, Ford hopes to develop a point-of-care test that would allow doctors to test for chlorinated lipids on site.

Researchers also hope their work leads to the development of countermeasures that can be taken to save lives in following chlorine gas attacks as well as accidental chlorine exposure.