MiR-223-3p inhibits rTp17-induced inflammasome activation and pyroptosis by targeting NLRP3.

The incidence of syphilis caused by Treponema pallidum subsp pallidum (T pallidum) infection is accompanied by inflammatory injuries of vascular endothelial cells. Studies have revealed that T pallidum infection could induce inflammasome activation and pyroptosis in macrophages. MicroRNA-223-3p (miR-223-3p) was reported to be a negative regulator in inflammatory diseases. The present study aimed to explore whether miR-223-3p regulates T pallidum-induced inflammasome activation and pyroptosis in vascular endothelial cells, and determine the mechanisms which underlie this process. MiR-223-3p levels in syphilis and control samples were determined. The biological function of miR-223-3p in the NLRP3 inflammasome and pyroptosis was evaluated in T pallidum-infected human umbilical vein endothelial cells (HUVECs). We observed a dramatic decrease in miR-223-3p levels in syphilis patients (n = 20) when compared to healthy controls (n = 20). Moreover, miR-223-3p showed a notable inhibitory effect on recombinant Tp17 (rTP17)-induced caspase-1 activation, resulting in decrease in IL-1ß production and pyroptosis, which was accompanied by the release of lactate dehydrogenase (LDH) in HUVECs. Additionally, the dual-luciferase assay confirmed that NLRP3 is a direct target of miR-223-3p. Moreover, NLRP3 overexpression or knockdown largely blocked the effects of miR-223-3p on T pallidum-induced inflammasome activation and pyroptosis in HUVECs. Most importantly, a notable negative correlation was observed between miR-223-3p and NLRP3, caspase-1, and IL-1ß, respectively, in the serum of syphilis patients and healthy controls. Taken together, our results reveal that miR-223-3p targets NLRP3 to suppress inflammasome activation and pyroptosis in T pallidum-infected endothelial cells, implying that miR-223-3p could be a potential target for syphilis patients.

rs294775 is a cis-regulatory SNP for human UGT2B10.

UGT2B10 is an important metabolism enzyme in human body and its substrates include multiple amine-containing compounds, especially nicotine, tamoxifen and multiple antidepressants. Multiple common SNPs have been observed in its promoter region, but their role in expression regulation has never been investigated. In this preliminary study, we identified a novel cis-regulatory SNP, rs294775, for UGT2B10 by plasmid construction, mutagenesis, and luciferase assay, whose mechanism was also investigated. Our work provides a basis for further pharmacogenetics study.

Acquired secondary syphilis in preschool children by nonsexual close contact.

Children may acquire syphilis as a consequence of nonsexual close contact if family members or caregivers are infected by active syphilis. We described 3 cases of acquired secondary syphilis in Chinese preschool children who contracted the disease from their caregivers to draw attention to the potential for syphilis patients to transmit Treponema pallidum to the children they are caretakers for.

MiR-216a-5p-containing exosomes suppress rTp17-induced inflammatory response by targeting TLR4.

Syphilis caused by Treponema pallidum (T. pallidum) infection is accompanied by inflammatory injury of tissue, and has a worldwide distribution and increasing incidence over the past decade. Tp17 has been reported to be a strong membrane immunogen, and was initially observed to play a role in inflammation during syphilis, reacting intensely with human syphilitic sera. We therefore used recombinant Tp17 (rTp17) as a stimulator in our study. Increasing evidence has demonstrated that microRNA (miRNA)-containing exosomes have emerged as a potential effective therapeutic target for many diseases. However, the biological functions and molecular mechanisms of miR-216a-5p in syphilis pathogenesis remain unknown. Our study first identified dramatically decreased miR-216a-5p in plasma of syphilis patients compared with the healthy control, which was negatively correlated with the expression of inflammatory cytokines, including IL-1ß, IL-6, and TNF-α. Moreover, endothelial cells treated with miR-216a-5p-containing exosomes significantly attenuated the rTp17-induced inflammatory response. More importantly, we identified that miR-216a-5p could bind to the 3'-untranslated region (UTR) of Toll-like receptor (TLR) 4 (TLR4), and overexpression of TLR4 largely rescued the miR-216a-5p-mediated suppression of rTp17-induced inflammatory cytokine production and the TLR4-MYD88 signaling pathway. Thus, our results reveal a novel role of miR-216a-5p-containing exosomes in endothelial cells, implying a potential therapeutic target for inflammation in syphilis patients.

Tumor necrosis factor -238A is associated with pediatric-onset generalized pustular psoriasis in Han patients in Eastern China.

The correlation between polymorphisms at the tumor necrosis factor (TNF) gene and generalized pustular psoriasis (GPP) has rarely been reported. The goal of this study is to investigate whether TNF polymorphisms (-238 A/G, -308 A/G, -857C/T) are associated with susceptibility to GPP in a Han population from Eastern China and to perform subgroup analysis to explore the influence of age onset. Polymorphisms were assessed by polymerase chain reaction amplification and resequencing in 91 GPP patients and 102 healthy controls. The frequencies of the TNF -238A allele and GA+AA genotypes were significantly higher in GPP patients than in those of healthy controls. The subgroup analysis revealed that these significant associations were still present between -238A variants and pediatric-onset GPP patients who developed GPP at less than 18 years old (PGPP), but not for patients with adult-onset GPP who developed GPP at 18 years old or more. There were no significant differences in genotype or allele frequencies of TNF -308 A/G and -857C/T polymorphisms between GPP and controls. In conclusion, individuals carrying TNF -238A may be more susceptible to PGPP.

Seroreactivity and immunogenicity of Tp0965, a hypothetical membrane protein of Treponema pallidum.

BACKGROUND: Treponema pallidum (T. pallidum) subsp. pallidum is the causative agent of syphilis. Analysis of recombinant antigens of T. pallidum led to the identification of potential candidate antigens for vaccine development and syphilis serodiagnosis. Tp0965 was predicted to be a membrane fusion protein and was found to be reactive with infected human sera in previous studies, but the results were controversial. In this research, the antigenicity and immunoreactivity of recombinant protein Tp0965 were assessed. METHODS: T. pallidum subsp. pallidum (Nichols strain) was propagated and isolated and the genomic DNA was extracted. The Tp0965 gene was amplified by polymerase chain reaction (PCR). Then the recombinant protein Tp0965 was expressed in Escherichia coli and purified by nickel-nitrilotriacetic acid (Ni-NTA) purification system. The reactivities of protein Tp0965 were examined by immunoblot analysis and indirect enzyme-linked immunosorbent assay. The antisera against protein Tp0965 were obtained by immune rabbits and the immunogenicity of antisera were detected by indirect enzyme-linked immunosorbent assay. RESULTS: Recombinant protein Tp0965 was expressed successfully in vitro. Immunoblot assay showed that the recombinant protein Tp0965 could be recognized by human syphilitic sera of all stages. Indirect enzyme-linked immunosorbent assay showed there were only 4 of 74 human syphilitic sera that failed to show reactivity to recombinant antigen Tp0965, and lack of reactivity of Tp0965 to all 28 uninfected sera. A low titer of antiserum against Tp0965 in immune rabbits could be detected after the third time of immunization. CONCLUSIONS: The recombinant antigen Tp0965 shows excellent sensitivity for the reactivity with sera from syphilitic individuals at all stages. The results also demonstrate a potential application for the serodiagnosis of syphilis.