Investigation of candidate exosomal miRNAs in the circulation in familial mediterranean fever (FMF) disease

Familial Mediterranean Fever (FMF) is inherited in an autosomal recessive manner. FMF is a monogenic disease however, phenotypic heterogeneity can be seen in different patient groups. Epigenetic factors including miRNAs might be a reason behind this heterogeneity. Exosomes are nanovesicles which are the carriers of many important molecules such as microRNAs, lipids, proteins and they can be found in many biofluids. The aim of this thesis is to determine the different exosomal miRNA signatures in FMF disease. For this purpose, three study groups (healthy control group, M694V/M694V homozygote FMF patient group and another systemic autoinflammatory disease group) were constituted for both adult and pediatric patients. After performing exosome isolation from plasma and serum samples of these individuals, characterization of exosomes was done with Transmission Electron Microscopy (TEM) and Flow Cytometry (FC). In TEM analysis, exosomes were visualized successfully with phosphotungstic acid (PTA). In FC analysis, exosome populations from plasma (68.1%) and serum (53.3%) were assessed through CD63 and CD81 surface markers. miRNAs were isolated from exosomes and the expression analysis of candidate miRNAs was done using qRTPCR. It was shown that miR-197-3p, miR-20a-5p, miR-374b-5p, miR-30e-3p, miR- 186-5p, miR-29c-3p were carried through exosomes and miR-197-3p, miR-20a-5p, miR-374b-5p were found to have differential expression pattern in systemic autoinflammatory disease patient groups. These miRNAs, which are shown to be circulating through exosomes and have varying expression levels between the patient and control groups, may be considered as biomarkers in the diagnosis and treatment of systemic autoinflammatory diseases in the future. Key words: Familial Mediterranean Fever (FMF), exosome, miRNA, qRT-PCR This thesis was supported by Hacettepe University Scientific Research Coordination Uni