Magnetic nanoparticle-assisted detection of peripheral blood miRNA biomarker characteristics in syphilis

Abstract

Syphilis is a chronic, systemic, transmitted disease that is highly infectious and harmful. This study was established to analyze the specificity of miRNA in distinguishing patients at different stages of syphilis, so as to provide a theoretical basis for using miRNA as a new diagnostic marker of this disease. The data were collected on patients with secondary syphilis (SS, n = 44) and early latent syphilis (ELS, n = 35) at Shanghai Skin Disease Hospital from March 2017 to March 2021, along with 46 healthy volunteers during the same period as healthy controls. We screened out miRNAs that might be differentially expressed in patients at different stages of syphilis on high-throughput sequencing technology, and then used magnetic nanoparticle-assisted qRT-PCR to verify their expression in the three groups. Receiver operating characteristic (ROC) curve analysis showed that miR-125a-3p could be used to distinguish the normal population from patients with syphilis. Meanwhile, miR-185-3p and miR-660-3p could be used to distinguish patients with ELS and SS, respectively. The combined diagnostic sensitivity of miR-185-3p and miR-660-3p was higher than that of each of these alone. Next, the toluidine red unheated serological test (TRUST) titers in the three groups were determined, with the analysis showing that miR-125a-3p did not have the ability to distinguish patients with different TRUST titers, while miR-185-3p and miR-660-3p levels decreased with increasing TRUST titer, indicating that the levels of miR-185-3p and miR-660-3p also had good diagnostic ability of TP activity. In conclusion, miRNA is differentially expressed in patients with syphilis at different stages of the disease and has good potential as a biomarker of syphilis. The combined use of miRNA increases the sensitivity for diagnosing syphilis at different stages.