Impact of E-cigarette Vapor Exposure on Renal Morphology and the Presence of Inflammatory Markers Using a Murine Model

E-cigarettes, invented in China in 2003, were marketed as a safer alternative to traditional cigarettes. In 2007, e-cigarettes were introduced  in the United States despite little evidence of their safety. Nearly twenty years later, emerging data, indicates potential public health risks associated with the use of e-cigarettes. The purpose of this project was to examine the effects on e-cigarette exposure on the microscopic anatomy of the mammalian kidney using the house mouse Mus musculus as a model. The specific goals of this project were to : (1) describe renal histology in animals exposed to e-cigarette vapor vs control animals, (2) quantify these changes using morphometrical analysis, and (3) optimize an immunohistochemistry protocol in preparation for future research. Following exposure of the experimental animals to strawberry-flavored Elf bar brand e-cigarette vapor, the kidneys were dissected and processed histologically (fixed using a preservative, embedded in paraffin wax blocks, sectioned at 7mm using a rotary microtome, and then mounted and stained using protocols for both standard hematoxylin and eosin staining and immunohistochemistry (IHC) . IHC involves an antibody cascade that localizes proteins of interest using an enzyme-substrate reaction between horseradish peroxidase (HRP) and diaminobenzidine (DAB). In the presence of the protein of interest, the DAB, a chromogen, induces a color change that can be visualized and quantified. The anatomical and physiological similarities of murine tissues compared to those of humans make this research relevant to human public health. Findings from this study can help individuals make more informed decisions concerning e-cigarette usage.