6th Annual Judith Ramaley Celebration of Research and Creative Scholarship
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Poster #94 Effects of The Hemolysin Produced by Uropathogenic Escherichia Coli on Female White Blood Cells Keegan Rosett Danielle Yeadon Kyle Winkelman Faculty Mentor: Nicole Aulik Urinary tract infections (UTIs) are a common problem for women in the United States. It has been estimated that one third of all women in the United States will suffer from a UTIs in their lifetime. Also, it is estimated that health care costs for UTIs add up to approximately 1.6 billion dollars annually. The leading cause of UTIs is due to uropathogenic Escherichia coli. Primarily, E. coli is a commensal; however, these uropathogenic strains are pathogenic and occasionally can cause other diseases in the body including the intestines and kidneys. There are many virulence factors that are recognized in the pathogenesis of UTIs. The hemolysin, a RTX toxin, is a very important virulence factor for uropathogenic E. coli. During UTIs, the hemolysin is up-regulated and it is believed that urine is the cause for the increase in hemolysin expression. Up-regulation of hemolysin is believed to be used in colonization of the epithelial cells of the bladder and the kidneys. This important toxin’s mechanism for causing white blood cell death is unknown. The majority of UTIs are known to affect women more then men where fifty to sixty percent of women will experience a UTI in their lifetime. The current hypothesis for the reason why women have more UTIs than men is that men have longer urethras than women. Currently, other theories have not been tested to see if other factors influence the frequency of UTIs in women. Neutrophils are a type of white blood cell that aid in the fight against infections and disease. Upon interacting with a pathogen, a neutrophil can produce an antimicrobial-studded DNA matrix called a neutrophil extracellular trap (NET). These traps will recognize pathogens and bind to them with a network of fibers, ultimately leading to the destruction of the pathogen. The goal for this research project is to quantify the amount hemolysin-induced cell death to human white blood cells. To be specific, the project will be working with macrophages and neutrophils purified from male and female donors and quantify the amount of extracellular trap formed in response to the E. coli hemolysin. We have observed a significant increase in the amount of neutrophil extracellular traps produced in response to the E. coli hemolysin from female neutrophils in comparison to male neutrophils. Also, we have observed fewer neutrophil extracellular traps produced by females who have had more than one hospital-confirmed UTI. Preliminary results have indicated that male macrophages also produce more extracellular traps than female macrophages. Similarly, we have observed more cell lysis of female red blood cells than male red blood cells. These data indicate that females that produce less extracellular traps are at risk of capturing and killing few E. coli cells than males. This could lead to the formation of a UTI in which the uropathogenic E. coli are not removed efficiently from. |
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