MYD88 dimerization controls the proliferative, invasive, and pro-inflammatory responses of synovial fibroblasts from rheumatoid arthritis patients

Purpose: We analyzed RNA-seq from rheumatoid arthritis synovial fibroblats and osteoarthritis syniovial fibroblast patients. Our goal was to evaluate the gene expression signatures after treatment with the MyD88 dimerization onhibitor ST2825 and identify its therapeutic potential. Methods: We analyzed bulk RNA-seq from RA synovial fibroblasts in diferent conditions: Untreated, ST2825-treated, LPS-treated, LPS+ST2825-treated. Aditionally, we analyzed bulk RNA-seq from OA synovial fibroblatss as a control. Collection of RNA was performed after 24 h of treatment and samples were sequenced to determine transcriptional changes and regulated processes. Results: paired-end reads were mapped to the homo sapiens GRCh37 genome assembly. RNA levels were normalized by RPKM and student's t-test. Conclusion: The aggressiveness of the RA SFs, in terms of their proliferation, invasiveness, and increased expression of pain and inflammation mediators was decreased by ST2825. Our data strongly suggest that targeting MyD88 dimerization could mitigate joint inflammation in RA SFs. Identification of the potential effect of the MyD88 dimerisation inhibitor ST2825 on pathogenic expression signatures to modulate joint inflammatory processes in RA patients.