With the BCG vaccine falling behind the times, and tuberculosis becoming increasingly resistant to all current treatments we are starting to see how deadly TB can be. It is currently one of the top 10 causes of death worldwide, with nearly 2 million deaths every year.
Tuberculosis has been our companion throughout our evolution and has adapted and changed with us in a continuous arms race for centuries. But despite this long-term relationship we know very little about how the infection develops and spreads within the body. Now, scientists are looking to change this.
In 2017 scientists from Gladstone Institutes, UCSF, UC Berkeley and UC San Diego; launched the Host Pathogen Mapping Initiative. This looks at taking a holistic view of the complex relationship between pathogens and their hosts. It looks into haw our own proteins, and those of tuberculosis interact, identifying potential new treatments.
Instead of sticking to the age old method of developing novel therapies, these scientists do not want to attack the bacteria's proteins, which eventually leads to mutation and resistance within the bacteria population. They instead intend to target human host proteins which are involved in common pathways, creating a treatment which can be used to treat multiple pathogens.
This could be the next step in the arms race, with the potential to treat not only TB but other infectious diseases which utilise the same pathways.
"Most therapies to fight infection currently target the virus or bacteria," said Krogan. "But viruses and bacteria mutate quickly and develop resistance to existing treatments. Instead, we want to target human host proteins involved in common pathways. This could allow us to develop therapies that use a single drug to treat multiple pathogens." The scientists have already identified commonly hijacked pathways in human cells. The human genes hijacked by tuberculosis, for instance, are the same genes mutated in many other disease states, including cancer and autism. Krogan added, "It's about finding the cell's Achilles' heel, and targeting it to fight many diseases at once."
