(420e) Can Soft-Matter Mechanics Provide New Avenues for Remediating (and even preventing!) Biofilm Infections?

Biofilms are systems of microbes that are bound to each other, and often to an external material, by a matrix of biopolymers and proteins. Therefore, biofilms are characterized by mechanical properties that are not present for systems of equivalent microbes in the non-biofilm state, with individual organisms suspended in fluid. We investigate how these mechanical properties contribute to the pathogenesis of biofilms, and how mechanical properties of the biofilm and/or its environment might be altered to make biofilms easier to clear, and even to prevent biofilms from developing.

We recently found that chronic, years-long biofilm infections evolve to change the production of matrix materials in such a way as to increase or maintain the mechanical robustness of the biofilm; we use shear rheology to measure mechanical robustness in terms of elasticity, yield strain and stress, and the energy input required to cause the biofilm to yield. More recently, we have begun investigations of how these mechanical properties of biofilms could impact the ability of the immune system to clear biofilms. Our preliminary results show that varying the elasticity of abiotic gels over the range measured for clinical biofilms has greatly influences how likely it is that neutrophils (phagocytic immune cells) will break off and engulf parts of the gel. This suggests that weakening relevant mechanical characteristics of biofilms may help to promote their clearance by neutrophils, which are the body's first responders and the primary defenders against neutrophils. We will present early results on approaches to disrupt biofilm mechanics by attacking the interactions between specific matrix materials.