Bacteria have evolved many clever tactics for invading our body’s cells while evading our natural bodies defenses. Now scientists studying one of the world's most virulent pathogens and a separate very common bacterium have discovered a new way that some bacteria can spread rapidly throughout the body by hitchhiking on our own immune systems cells.
The discovery revolves around the interaction between F. tularensis a bacterial infection and immune cells known as macrophages. These large cells specialize in detecting foreign invaders, which they typically swallow whole. Testing macrophages and F. tularensis against each other in cell culture experiments, the research proves that the bacteria are able to go undetected through macrophage cell defenses and reside within the immune response
Bacteria not only survived inside the macrophages but also interfered with the natural cell death process that is typically triggered in infected cells in order to protect the whole of the organism. The result is that F. tularensis keeps its macrophage host alive for about 36 hours, giving the pathogen plenty of time to spread to other cells.
Even more remarkable was how the bacteria moved from cell to cell: through a little-understood natural process called Trogocytosis. During Trogocytosis, two cells bump against each other, exchange a few surface proteins and then separate. It was during these brief, hug-like encounters that F. tularensis slipped quietly from one macrophage to another. This is an unbelievable finding that is only recently looked into as cells are becoming more vulnerable to infections conditions. Science has yet to prove a strong theory and experiment against the impending threats we have discovered.