BME Distinguished Seminar Series: Christopher J. Hernandez, Ph.D., UCSF

Title: "Microbiology in Biomechanics and Disease"

Abstract: My laboratory interactions between microbiology, biomechanics and materials science. Here, I discuss the effects of the gut microbiome on the musculoskeletal system and the effects of bacterial biomechanics on infection. We have found that the gut microbiome can regulate the mechanical performance of bone extracellular matrix. Here we use micropillar-based materials testing methods to show that changes in the gut microbiome can impair or improve bone matrix strength and toughness – an effect that is reversible in an adult skeleton. These findings raise the intriguing possibility that microbiome-based interventions may be useful to enhance bone matrix material properties. In addition, I will discuss recent studies examining how bacteria infiltrate extracellular matrices and thereby evade immune detection. Using a combination of nanofluidic systems and a novel high-throughput benchtop assay of bacterial cell stiffness we find that clinical isolates from bone infection are more deformable in patients with persistent infections, raising the possibility that low bacterial stiffness is a virulence factor that can contribute to the persistence of clinical infections.