Targeted ablation of bladder-resident uropathogenic bacteria with a novel cell penetrating dye - Urinary Tract Infections (UTIs), one of the most prevalent bacterial infections globally, present a formidable health challenge, especially considering that 25-50% of UTIs, even with antibiotic intervention, either persist or recur within a six-month frame. The intricacy of managing recurrent UTI (rUTI) is amplified due to the infiltration of the bladder epithelium by uropathogenic bacteria. Intracellular bacteria are safeguarded from antibiotics that cannot penetrate epithelial cell membranes, thus facilitating their persistence to initiate recurrent infections. Noteworthy studies by Co-Is De Nisco and Zimmern, utilizing 16S rRNA fluorescence in situ hybridization to analyze bladder biopsies from women with rUTI, have confirmed the existence of tissue- invasive bacteria within the bladder wall. The majority of available therapies are unable to target these tissue- resident bacteria. Electrofulguration (EF) is a therapy used to eradicate tissue-embedded bladder bacteria in women with antibiotic-refractory UTI. By cauterizing visibly inflamed bladder areas, which are presumed to harbor tissue- resident uropathogens, this treatment has provided symptomatic relief and reduced clinical incidence of rUTI. However, its drawbacks include a six-month recovery period, pain, and the inability to differentiate between infected and healthy tissue. Fulguration guidance relying on visual signs of inflammation hinders the specific targeting of infected areas, potentially leading to the fulguration of healthy tissue and incomplete removal of infected tissue. Therefore, targeted ablation of infected bladder areas is necessary to optimize outcomes for rUTI patients and minimize pain and recovery duration. A breakthrough from the Gassensmith lab has led to the development of BactVue, a novel tool hypothesized to enable the targeted ablation of infected bladder tissue, potentially revolutionizing current treatment paradigms for antibiotic-refractory UTI. BactVue, a bacteria-selective stain, can permeate the cellular bilayer of epithelial cells, bind to intracellular bacteria, and, when irradiated with an 808 nm laser, fluoresce to reveal the location of intracellular bacteria and cause photothermal heating that kills the bacteria and selectively destroys the infected tissue. The proposal aims to define the potential of BactVue to specifically target and ablate infected bladder tissue through photothermal heating, hypothesizing that BactVue binds selectively to both Gram-negative and Gram-positive bacteria over mammalian cells. The proposal outlines two primary aims: to demonstrate the ability of BactVue to stain diverse intracellular uropathogenic bacteria selectively and to leverage photothermal heating to enable the targeted killing of cells harboring pathogenic bacteria labeled with BactVue. The project promises to advance significantly the development of this transformative tool for clinical applications in managing antibiotic-refractory rUTI.
