Researchers Find How Tuberculosis Bacterium Invades Immune Cells

U.S. researchers said Thursday that they had discovered how the tuberculosis bacterium and its cousin leprosy invade cells, and said this could open new avenues to treating the two ancient diseases.

The bacteria hijack one component of the immune system and use it like a Trojan horse to sneak into immune cells known as macrophages, which they then destroy, the researchers reported in the journal Science.

Scientists have known the tuberculosis bacillus invades macrophages, the immune cells that literally eat invaders such as bacteria, but they did not know how it got in.

Tuberculosis and other mycobacteria can grab onto a protein called C2a, which attracts the attention of the macrophages.

Once inside the macrophage, the mycobacterium thrives, eventually kills the macrophage and thus causes disease.

Researcher Jeff Scholey said knowing this has opened new avenues for fighting the diseases. Perhaps a vaccine or an antibiotic could introduce an antibody that would block the connection between C2a and the bacteria, he said.

Tuberculosis infects an estimated one-third of the world’s population. It kills 3 million people a year.