Discipline: Biological Sciences
Kathlyn Hornberger - Milwaukee School of Engineering
Co-Author(s): Vijesh Bhute, University of Wisconsin-Madison
Intestinal inflammation causes a variety of inflammatory bowel diseases. Human intestines are home to over 800 species of gut microbes that serve a variety of functions, including the regulation of intestinal inflammation. The human cancer carcinoma Caco-2 cell line differentiates in monolayers to resemble human intestinal epithelial cells and can be used as an in vitro model of human intestines. Lactobacillus casei is a common probiotic that plays a role in regulating intestinal inflammation. The effects of six different strains of Lactobacillus casei on Caco-2 cells were observed. L. casei or its supernatant was added to differentiated Caco-2 cells. Effects of inflammation was observed using two methods: measuring transendothelial electrical resistance (TEER), a measure of the tightness of the Caco-2 barrier, and extracting RNA to analyze inflammatory gene expression. Caco-2 cells were seeded in Transwells and 12well plates. TEER was measured daily as cells differentiated and the experiment started when the TEER stabilized. To observe changes in the tightness of the Caco-2 barrier, L. casei or its supernatant was added and TEER was measured over time. The presence of L. casei increased the TEER in Caco-2 cells over time, while the supernatant alone had no effect. L. casei was added to 12-well plates of differentiated Caco-2 cells and RNA was extracted after two hours. Quantitative PCR was performed for five pro-inflammatory and one anti-inflammatory gene. The presence of L. casei reduced expression of the pro-inflammatory gene interleukin-1 alpha. Results varied for other genes. The increase in TEER and regulation of inflammatory cytokines show that L. casei plays a role in the inflammatory response of Caco-2 cells. This preliminary research shows the potential to utilize L. casei as a treatment for inflammation in vivo. Future research can focus on engineering these gut microbes to improve intestinal health.
Funder Acknowledgement(s): Emerging Frontiers in Research and Innovation (EFRI-REM); University of Wisconsin - Madison REU program
Faculty Advisor: Sean Palecek,