Are hot dogs good for your health?

Hot dog hazard

The natural habitats of the pathogenic bacteria Listeria monocytogenes are soils, vegetation and sewage. From here it finds its way onto fruit and vegetables and also contaminates food that is to be kept in the refrigerator. Hot dogs, for example, can be a real source of tricky pathogens.

Even though effective antibiotics are currently protecting most people from a fatal invasion, a research team from L'Institut Pasteur in Paris as a precaution already in the future. Passing on antibiotic resistance may require new therapeutic approaches. To make this possible, Pascale's team followed up on Cossart Listeria on its way from the gastrointestinal tract via the lining intestinal cells to the bloodstream.

Previous work had a surface protein of Listeria discredited. The so-called internalin connects to a receptor on cultivated intestinal cells. This attachment opens the door to the cells of the digestive tract for the bacteria. Once inside, it overcomes the cells and then enters the bloodstream. The closer follow-up in the animal model proved to be difficult, since both rats and mice produce a variant of the protein modified by humans.

Guinea pigs, however, were suitable, as were transgenic mice, which now produced the human version of the cadherin receptor on the surface of their intestinal cells. Now the animals were given two different orally Listeria-Trunks fed. While the wild type resulted in death in most cases, the internalin-free mutant did not seem to be able to cross the barrier in the digestive tract. The animals stayed alive. Now Internalin shares the notoriety of a virulent factor with other already proven culprits. A pore-opening toxin, for example, helps Listeria in the process of escaping the vacuoles.

Nonetheless, in Cossart's opinion, a few questions remain unanswered. Like how the two responsible proteins find each other. Because the cadherin protein sits quite inaccessibly between two intestinal cells. Cossart speculates that the cell connections open for a short time, thus giving the bacterium access during its three-day life. The researchers also want to investigate how the bacterium crosses other cell boundaries in the human body. For example to attack the brain or to become dangerous to unborn children in the womb.