Biophysical Society: Researchers Discover How TB Bacteria Use a “Stealth” Mechanism to Evade the Immune System

21 February 2026

Biophysical Society press release

Scientists have uncovered an elegant biophysical trick that TB bacteria use to survive inside human cells, a discovery that could lead to new strategies for fighting TB.

The research, published in bioRxiv, revealed that mycobacteria release tiny packages called extracellular vesicles that fuse with the membranes of immune cells. These vesicles contain specialized lipids — fatty molecules — that make the cell membrane more rigid.

Normally, when our immune cells engulf harmful bacteria, they trap them in a compartment called a phagosome, which then fuses with another compartment called a lysosome. Lysosomes contain digestive enzymes that break down and destroy the bacteria. However, the team discovered that by stiffening the phagosome membrane, mycobacteria prevent this fusion from occurring — essentially building a protective bunker around themselves inside our own cells.

Read the full press release here.

Source: Biophysical Society