microRNA-200 Family Expression Level Changes in Stimulated THP-1 Cells Following NLRP3 Inflammasome Activation

Abstract: Innate immunity is the immune systems rapid responses to infection after being attacked by a pathogen. Inflammatory responses are activated by the detection of pathogen-associated molecular patterns and danger-associated molecular patterns through pattern recognition receptors on inflammatory cells. NLRs are activated by intracellular PAMPs which warn cells of damage and have a major role in initiating the innate inflammatory responses as well as the development of infectious and inflammatory diseases. NLRP3 is a very large multiprotein complex and is the most studied inflammasome. The NLRP3 Inflammasome follows a two-signal model for activation, signal one forms the NLRP3 complex and signal two activates the inflammasome. NLRP3 initiates an inflammatory form of cell death called pyroptosis and triggers the release of pro-inflammatory cytokines IL-1β and IL-18. The miR-200 family has five members, miR-200a, miR-200b and miR-429 located on chromosome 1 and miR-200c and miR-141 located on chromosome 12. In this study, THP-1 cells were differentiated with PMA then stimulated with LPS and ATP. Various time samples were collected and isolated to obtain miRNA. Two-step RT-qPCR was then performed to quantitively monitor the changes in miRNA-200 family expression levels. The purpose of this study was to observe how miRNA-200 family expression levels change in stimulated THP-1 cells as the NLRP3 inflammasome is activated. This became a pilot study as all biological replicates could not be analyzed, miR-200 family is showing a potential response to the activation of the NLRP3 inflammasome and they should be investigated further.