Expressions of interferon-stimulated genes in peripheral blood mononuclear cells from patients with secondary syphilis

Background: Syphilis is a sexually transmitted disease that threatens human health worldwide. However, the immune regulation cascade caused by treponemia pallidum (TP) infection remains still largely unclear. Methods: To investigate the expression of ISGs in secondary syphilis (SS), we recruited 64 patients with SS and equal number of healthy participants to obtain their peripheral blood mononuclear cells (PBMCs). qRT-PCR was performed to estimate the expression of interferon-stimulated genes (ISGs) including CXCL10, OAS3, OAS1, MX1, IFIT3, IFIT2, IFI6 and AIM2. Receiver-operating characteristic (ROC) analysis was adapted to diagnostic value of these genes to distinguish healthy controls and patients with SS. Results: ISGs including CXCL10, OAS3, OAS1, MX1, IFIT3, IFIT2, IFI6 and AIM2 were all upregulated in PBMCs of patients with SS. Area under the ROC curve (AUC) of the 8 ISGs were all more than 0.5. IFIT3 exhibited the highest diagnostic value, followed by AIM2, IFIT2 and CXCL10, according to the Yoden Index. Conclusion: ISGs including CXCL10, OAS3, OAS1, MX1, IFIT3, IFIT2, IFI6 and AIM2 were upregulated in patients with SS and they have diagnostic value for syphilis.

Automated summary

The study found that ISGs were upregulated in patients with secondary syphilis, which have diagnostic value for distinguishing syphilis patients from healthy individuals.