Cardiac Responses to Klebsiella pneumoniae Infection; Investigating Its Role in Sepsis and Endocarditis 2251186

Abstract Introduction Sepsis causes nearly 11 million deaths across the globe and about 350,000 per year in the United States. Sepsis can be induced by various pathogens however, Klebsiella pneumoniae, a gram-negative bacterium, is particularly adept at disseminating through the blood to many distal sites from the lung. K. pneumoniae (Kpn) can cause various illnesses such as pneumonia, meningitis, endocarditis, wound infections, and is a leading cause of bacterial sepsis. The purpose of these studies is to observe how Kpn affects the resident cardiac cells. Methods These studies will be important in elucidating how cardiomyocytes respond to infection with Kpn by using two approaches to uncover how these cells respond to infection. One approach consists of harvesting tissue samples from uninfected and infected mice to observe the in vivo response. Collected tissues were processed using histology techniques then immunofluorescence assays were performed to help delineate immune responses in the heart at post infection. The second approach involved directly infecting rodent and human cardiac cell lines to study the susceptibility of these cells in vitro. Using these two methods, the goal is to define how resident heart cells respond to Klebsiella induced endocarditis. Results Preliminary results show that Kpn infection significantly alters cardiac tissue both in vivo and in vitro. Histological and immunofluorescence analyses demonstrate increased immune cell infiltration and signs of cardiomyocyte stress and damage following infection. Conclusion Our results highlight that Klebsiella pneumoniae infection significantly alters cardiac tissue in vivo and in vitro. Histological and immunofluorescence analyses demonstrate increased signs of cardiomyocyte stress and damage following infection. The data suggest that K. pneumoniae may play a direct role in cardiac dysfunction during sepsis and in the development of bacterial endocarditis, underscoring the importance of early detection and targeted therapies. Funding Source Internal funding - A&M San Antonio Foundation Topic Categories Microbial, Parasitic, and Fungal Immunology (MPF)