Pushing boundaries: mechanisms enabling bacterial pathogens to spread between cells

Area of Science:

• Microbiology
• Cell Biology
• Pathogenesis

Background:

• Intracellular bacterial pathogens spread between host cells, a key step in human disease.
• Pathogens like Shigella, Listeria, Rickettsia, and Burkholderia manipulate host actin cytoskeleton for cell-to-cell spread.
• This process involves forming membrane protrusions that extend into adjacent cells.

Purpose of the Study:

• To review the mechanisms of intercellular spread utilized by intracellular bacterial pathogens.
• To highlight the interactions between bacterial and host factors driving this spread.
• To focus on the formation and resolution of protrusion structures during intercellular movement.

Main Methods:

• Literature review of recent research on bacterial intercellular spread.
• Analysis of host-pathogen interactions.
• Focus on actin cytoskeleton manipulation and membrane protrusion dynamics.

Main Results:

• Intracellular bacteria hijack host actin to create membrane protrusions for cell entry.
• Protrusions are resolved into double-membrane vacuoles (DMVs) from which bacteria escape.
• Bacterial escape into the cytosol allows for repeated rounds of intercellular spread.

Conclusions:

• Understanding protrusion formation and resolution is crucial for deciphering bacterial pathogenesis.
• Host-pathogen interactions governing actin dynamics are central to intercellular spread.
• This mechanism is vital for the dissemination of multiple significant intracellular bacterial pathogens.