Immune cells or gallstones are the culprits

scientists have discovered DNA and an enzyme on the surface of human gallstones. Photo Source: Munoz et al./Immunity
It has long been known that gallstones are grown from crystals in the gallbladder, but it is not clear how these crystals bind together. Now it seems that immune cells are to blame - a discovery that could lead to new treatments. The results were published in the journal Immunization.
Herrmann and colleagues at the University of Friedrich-Alexander in Germany found this phenomenon while studying small stones in the bile of gallstone patients.
the surface of these small stones showed clear signs of extracellular trapping nets in neutral granulocytes. The latter is a DNA adhesive network released by immune cells to capture invasive microorganisms. The presence of large groups of DNA and an enzyme used by neutral granulocyte immune cells suggest that these cells have been targeting gallstones.
to test this conclusion, the researchers mixed cholesterol crystals with human neutral granulocytes in the lab. Neutral granulocytes react by shooting DNA into crystals.
when they shake and rotate gallstones while neutral granulocytes are present, gallstone surfaces quickly collect neutral granulocyte DNA. These sticky nets pull cholesterol and calcium crystals together to form larger stones.
stones formed in this way may be ignored until stones enter the small intestine or stay in the bile tube from the gallbladder and cause severe pain.
these findings may lead to preventive treatment for gallstones. Herrmann and colleagues found that changing genes or using drugs to disrupt the formation of these trapping nets resulted in fewer and smaller gallstones in mice.
one of the drugs tested by the researchers is called metolor, which is currently used to treat some types of heart disease. Human trials are also needed to see if the drug also helps prevent gallstones, Herrmann said. (Source: Zong Hua, China Science Journal)
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