When bacteria invade our lungs, our bodies counter-attack by launching a rapid immune response to fight the infection. Yet, this all happens much faster than we can reasonably account for with our current knowledge of the immune system.
So, how do our bodies respond so quickly to a bacterial infection?
This is a question that the researchers from the KU Leuven Department of Cellular and Molecular Medicine have been trying to answer. Their research, published recently in Nature Communications, used mice to investigate how molecules called lipopolysaccharides, commonly found on the surface of many bacteria, trigger such a fast immune response.
They found that, in addition to triggering the slower immune response, these molecules also activated an ion channel in the lung cell. This channel has the impressive name of ‘transient receptor potential vanilloid 4 cation channel’ or TRPV4 to you and me.
When they’re activated, these TRPV 4 channels open in seconds to let calcium flow into the lung cells, triggering a range of antibacterial responses including the production of bactericidal nitric oxide, bad news for the invading bacteria.
“Our study shows that our body’s strategy to fight off bacterial infections is not limited to previously identified immune pathways,” Professor Karel Talavera Pérez, who led the research team, said, “So-called TRPV4 ion channels play a role as well: they are essential to our body’s earliest defence mechanism against bacterial invasion. If we want to develop more effective treatments, these ion channels are well worth investigating in greater detail.”
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