OP0256 Changes of Microrna Expression in Lymph Node Stromal Cells of Rheumatoid Arthritis Patients

Background Lymph node stromal cells (LNSC) build the scaffold that enables migration and interaction of lymphocytes in the lymph node. More recently, it has been shown that during inflammation LNSC play a crucial role in shaping the immune response and maintaining tolerance. However, little is known about the underlying molecular mechanisms. Objectives In the current study we analyzed the expression of microRNAs in LNSC from healthy individuals, RA patients as well as anti-CCP positive arthralgia patients with a high risk to develop RA. Methods Needle biopsies of inguinal lymph nodes were strained through a 70μm nylon mesh and the resulting stromal part was cultured in DMEM with 10% FCS. Adherent cells were passaged 4 times before total RNA was isolated. RNA was reverse transcribed with specific microRNA stem loop primers and loaded onto TaqMan® Low Density Arrays (Life technologies, MicroRNA Panel A). The data were analyzed on the Expression Suite software using RNU48 as endogenous control, and differentially expressed microRNAs were re-measured in single-assay reactions. Results 4 microRNAs appeared differentially regulated between healthy individuals (n=5) and RA patients (n=6) with a p-value