A MIT study has showed a new way of immunizing against microorganisms like Salmonella that infect the stomach and intestines. These microorganisms can trigger foodborne illnesses such as acute gastroenteritis or food poisoning. Salmonella is estimated to cause one million foodborne illnesses in the USA each year. The results have been described in Proceedings of the National Academy of Sciences. Antibiotics can effectively kill harmful bacteria. But they can also attack beneficial bacteria. In addition, growing drug resistance is a big health threat. So alternative ways of treating infections are in need. MIT scientists focused on a substance that helps bacteria like Salmonella to clean iron, a critical metal for many species. The team found that immunization against this substance results in antibody formation, which inhibits bacterial growth and then decreases bacterial quantity. Elizabeth Nolan assessed that their method is narrow-spectrum, which is a big advantage over antibiotics. Some microorganisms depend on siderophores (small, high-affinity iron chelating compounds) to obtain iron. In the stomach and intestines, bacteria secrete siderophores into the gut. When bacteria obtain iron, they reabsorb siderophores. Nolan and colleagues looked at a subset of siderophores produced by several gut pathogenic bacteria like Salmonella. Human bodies generate the protein lipocalin 2 to prevent bacteria from obtaining iron by inhibiting blocking siderophores, but lipocalin 2 fail to work when it comes to Salmonella because lipocalin 2 can not block Salmonella siderophores. Nolan's team used the siderophore-CTB complex to immunize mice and then infected the mice with Salmonella. The mice eventually had high antibodies against the siderophores, and had fewer Salmonella in their gut. Need mouse polyclonal antibody? Visit CusAb's website.
