The study of exosomal miR-148a-5p as a serum biomarker and its mechanism of rheumatoid arthritis

WANG Lili; CHEN Junmeng; CHEN Jingjiao; LIU Fuqun

doi:10.13431/j.cnki.immunol.j.20240109

Abstract：Objective To evaluate the potential of serum exosomal miR-148a-5p as a biomarker and to investigate its role in the pathogenesis of rheumatoid arthritis(RA).Methods A total of 80 participants(30 healthy controls,HCs;50 RA patients)were recruited.Serum exosomes were extracted and identified.The expressions of exsomal miR-148a-5p will be screened by next-generation sequencing,validated by qRT-PCR and assessed its clinical significance.Target genes and their functions were determined by the luciferase reporter assays,cell transfection,and ELISA.Results Fifty-five differentially expressed serum exomiRNAs were identified(44 upregulated,11 downregulated).The high expression of the exo-miR-148a-5p in the serum of patients with RA was validated by qRT-PCR,comparing to HCs(P<0.000 1),which showed a strong correlation with the disease activity score(DAS)28,rheumatoid factor(RF),and erythrocyte sedimentation rate(ESR)and exhibited higher sensitivity and specificity of diagnostic(AUC 0.8633,95%CI 0.77～0.95).CREB5 was the potential target gene of miR-148a-5p.CCK-8 assays showed that miR-148a-5p mimic significantly promoted proliferation of MH7A and M0 macrophages at 48 h and 72 h(P<0.005).The miR-148a-5p inhibitor inhibited proliferation of MH7A and M0 macrophage at 48 h slightly(P<0.05),and better effects shown at 72 h(P<0.001).Additionally,miR-148a-5p mimic significantly reduced CREB5 protein expression in MH7A cells and increased the levels of MMP3 and CXCL10 in culture supernatant(P<0.001),which could be reversed by miR-148a-5p inhibitor.However,miR-148a-5p had no impact on protein expression of RBMXL1 or CREB5 in M0 macrophages.Conclusion Serum exosomal miR-148a-5p is a diagnostic marker and involves in the pathogenesis of RA,which promotes MH7A cell proliferation by affecting protein levels of CREB5 and excessive secretion of MMP-3,CXCL10.