Huang Jianyong's research group from the School of Engineering has made progress in the treatment of bacterial infections by regulating the stiffness of the matrix

Pathogenic bacteria hijack and internalize into host cells to cause persistent infection and secondary infection

On August 27, 2021, the research group of Prof.

Figure 1: Schematic diagram of bacterial internalization mode and antibacterial treatment by regulating the stiffness of extracellular substrate

In order to clarify how the stiffness of the extracellular matrix regulates the invasion law of bacterial internalization, the researchers established a cell-bacteria interaction model based on a flexible substrate, and found that as the substrate stiffness increases, the total amount of internalized bacteria decreases.

Figure 2: Bacterial traction determines the internalization mode of bacteria on a monolayer of cells (A) Measurement of cell traction before and after infection with different soft and hard substrates (B) Cell traction with time (C) Bacteria in the site with high cell traction (D) Bacteria internalize outside the cell monolayer with high cell traction

The researchers further revealed how the stiffness of the extracellular matrix regulates the mechanobiological laws of antimicrobial drugs for the treatment of internalizing bacterial infections

To sum up, this article reports the regulation of extracellular matrix stiffness for pathogens’ invasion and internalization of host cells, and discovers the internal mechanism of matrix stiffness governing pathogen aggregation/diffuse invasion of host cells, revealing the accumulation of antibiotics in cells And its quantitative dependence on the removal efficiency of internalized bacteria and the microenvironmental factors of matrix mechanics

Liu Xiaoye, a postdoctoral fellow at the School of Engineering of Peking University (currently a lecturer at Beijing Agricultural College) is the first author of the paper, and Huang Jianyong is the corresponding author.