By Alexis Miller, Yasminaa Shehata, Chelsea Barrera-Guzman

Faculty Mentor: Dr. Laura Sipe

Abstract

Inflammatory diseases are one of the most common causes of death. Significant harm is introduced to the innate immune system; responsible for pathogen recognition, immune cell recruitment, and defending the host against the foreign pathogen via induction of inflammation. The Toll-like receptor signaling pathway binds to the ligand lipopolysaccharide (LPS) to induce inflammatory markers within macrophages. For this experiment, RAW 264.7 macrophages stimulated with LPS were used to analyze if vitamin D (VD) has anti-inflammatory functions. VD has been proven to display benefits to one’s health like acting as an immunomodulator by assisting immune cells with the inhibition of pro-inflammatory cytokine secretion within macrophages. In this experiment, we aim to analyze the anti-inflammatory effects of VD (0.25uM, 0.50uM, and 1uM) on LPS-stimulated macrophages to determine if VD has an anti-inflammatory effect. To determine this, an MTT assay (determines cell viability), nitric oxide (NO) assay (quantifies NO production),and phagocytosis (immunofluorescence) were performed. MTT assay determined that LPS stimulated macrophages exhibited higher cell proliferation only at lower doses of VD (0.25uM and 0.50uM), indicating lower doses had no cytotoxicity compared to 1uM VD. NO assay exhibited LPS unstimulated significant statistics for 0.25uM and 0.50uM. Immunofluorescence exhibited phagocytic activity. In this study, we concluded that VD exhibits partial anti-inflammatory responses on RAW 264.7 macrophage cells. Further research will be needed to prove the extent of anti-inflammatory effects VD has on RAW 264.7 macrophages.