The immune system is under the constant challenge of specifically detecting dangerous microbes to remove them. Dr. Andrea Puhar and her team at The Laboratory for Molecular Infection Medicine Sweden (MIMS) at Umeå University, discovered that gut cells sense harmful bacteria through the mechanical force exerted on their cell surface during bacterial invasion. A protein called PIEZO1, which is able to sense mechanical signals, is necessary to detect invading bacteria. Activation of PIEZO1 during infection triggers a protective immune response. The study is now published in the scientific journal Cell Reports.