PROJECT SUMMARY (See instructions): Background: Despite extensive investment in better healthcare practices, hospital acquired infections (HAIs) remain a major public health concern. Currently, the Centers for Disease Control and Prevention (CDC) estimate that about one in twenty-five patients receiving treatment at acute care hospitals in the United States have acquired a preventable infection, often resulting in chronic, non-healing wounds. Colonizing bacterial biofilms are a major contributor to delayed healing; however how the metabolic phenotype of a colonizing biofilm influences the wound healing process remains largely unknown. Overall Hypothesis: Our preliminary findings support to our broad research hypothesis that bacterial biofilms mediate specific pathological effects against host innate immune cells within the wound environment, resulting in deviation from the normal wound healing process and leading to wound chronicity. As a step towards the ultimate goal of discovering novel therapeutic targets for chronic wounds, this proposal will achieve the following Specific Aims: Investigate whether exposure to Staphylococcus aureus and Pseudomonas aeruginosa biofilms in vitro results in a metabolic deviation in innate immune cells that drives a phenotypic shift towards inflammation. This aim will capture the metabolic interactome of host and pathogen for both a key Gram-positive and Gram-negative pathogen, providing important insight into how metabotype of pathogen regulates macrophage polarization. Aim 2: Explore whether a correlation between bacterial colonization, metabolic landscape, and macrophage polarization is related to non-healing in wounds. This aim will take the first step towards clinical translation of the hypothesis that metabolic immunomodulation of macrophages is key to failure of wounds to heal.