30. maj 2022

A novel way how bacteria block the host cells immune-defense

Cell Biology and Physiology

A group of scientists at the Kings college in London lead by Charlotte Odendall together with several collaborating groups from different countries including the research group of Martin Berchtold at the Department of Biology KU, discovered a new trick how bacteria can block the cells defense system.

Shigella

The findings has just been published in the scientific journal Cell.

The pathogenic Shigella bacteria, a major cause of dysentery, invade epithelial cells of the intestine and inject a number of effector proteins into the host cells allowing these pathogens to survive and reproduce in the host cells.

The OspC family, a group of effector proteins, is known to suppress the host antimicrobial defense by inhibition of programmed cell death. On the other hand, much less is known about how the interferon-mediated cell defense system is used to fight bacterial invasion and whether bacteria can interfere with it. For the first time, the study by Odendall et al. shows evidence that OspC family proteins can block the interferon mediated pathway by binding to the calcium sensor Calmodulin and thereby inhibit a pathway leading to the activation of interferon-stimulated genes.

The observation that OspC proteins of several other human pathogens bind Calmodulin and inhibit interferon signaling indicates that the newly discovered mechanism may be common for different human pathogens. Targeting the interferon pathway by interfering with the calcium/Calmodulin signaling enlarges the so far known repertoire of bacterial strategies for a successful infection and invasion.

Kontakt

Professor Martin Berchtold
Section Cell biology and Physiology
Department of Biology
Mail: mabe@bio.ku.dk 

Helle Blæsild
PR & Communication
Department of Biology
Mail: helleb@bio.ku.dk
Tel: +45 2875 2076