Dissemination of gut bacteria to the liver and spleen of mice is comparable in the presence (closed triangles) and absence (open triangles) of Peyer's patches.
According to conventional wisdom, pathogenic gut bacteria spread to distant tissues via an orderly march from gut to local lymph nodes (LNs) and then on to distant organs. But some mutant bugs that cannot invade the lymphoid tissues of the gut can still spread, hinting at the existence of an alternative route.
Barnes and colleagues infected mice orally with Yersinia pseudotuberculosis. They noted two waves of bacteria that spread to both the spleen and liver in the infected mice. The first wave occurred within 30 minutes of infection and was rapidly cleared from these distant organs. The second...
