Tuberculosis is an infectious disease caused by the bacterium Mycobacterium tuberculosis. The disease tends to affect the lungs, although other parts of the body can also become infected. Most infections do not lead to any symptoms (‘latent tuberculosis’). However, around 10 percent of infections turn into an ‘active disease’, and this can lead to a high fatality rate. With this symptoms include chronic coughing with blood-containing sputum, fever, and weight loss.
The disease is spread through the air when those who are infected cough, spit, or sneeze. Medical diagnosis is made via chest X-rays and microscopic stains made of body fluids.
The new insight into how the human body fights infection from Mycobacterium tuberculosis opens up new ways to combat the disease. The British researchers found that the body’s natural means from combatting the disease is based on specific immune cells called macrophages. These immune cells function to surround the invasive bacteria. At this point the immune cells release phagosomes which can engulf the bacteria and release enzymes that are able break down each bacterium and destroy it.
In many cases, however, the bacteria are able to launch a counter-offensive by puncturing a hole through phagosome membranes. The organisms then invade the cells. These processes were shown using new imaging systems.
This advanced imaging enabled the scientists to show how the bacteria can be stopped. This involves a protein described as Rab20, as set out in the research protocol. The protein functions to signal the reinforcement the cell membrane of the phagosomes. Once the signal is sent, the bacteria become locked inside membrane sacs. At this stage bacteria-destroying antibacterial components are released.
Understanding this presents the basis for a new tuberculosis combating treatment. This is set out by Dr. Maximiliano Gutierrez, who notes: “the only way you can understand what is going on is to image cells in real time at very high resolution. We are one of the few labs in the world that can perform long-term live cell imaging at sub-cellular resolution with the safety infrastructure required to work with a life-threatening bacterium.” This knowledge should deliver an artificial means for boosting the body’s natural defenses.
