Project description:Treponema pallidum ssp. pallidum, the causative agent of syphilis, can now be cultured continuously in vitro utilizing a tissue culture system, and the multiplication rates are similar to those obtained in experimental infection of rabbits. In this study, the RNA transcript profiles of the T. pallidum Nichols during in vitro culture and rabbit infection were compared to examine whether gene expression patterns differed in these two environments. To this end, RNA preparations were converted to cDNA and subjected to RNA-seq using high throughput Illumina sequencing; reverse transcriptase quantitative PCR was also performed on selected genes for validation of results. The transcript profiles in the in vivo and in vitro environments were remarkably similar, exhibiting a high degree of concordance overall. However, transcript levels of 94 genes (9%) out of the 1,063 predicted genes in the T. pallidum genome were significantly different during rabbit infection versus in vitro culture, varying by up to 8-fold in the two environments. Genes that exhibited significantly higher transcript levels during rabbit infection included those encoding multiple ribosomal proteins, several prominent membrane proteins, glycolysis-associated enzymes, replication initiator DnaA, rubredoxin, thioredoxin, two putative regulatory proteins, and proteins associated with solute transport. In vitro cultured T. pallidum had higher transcript levels of DNA repair proteins, cofactor synthesis enzymes, and several hypothetical proteins. The overall concordance of the transcript profiles may indicate that these environments are highly similar in terms of their effects on T. pallidum physiology and growth, and may also reflect a relatively low level of transcriptional regulation in this reduced genome organism.
Project description:Treponema pallidum subspecies pallidum (T. pallidum) infection induces significant immune responses, resulting in tissue damage. Gene expression plays an essential role in regulating the progression of syphilis infection. However, little is known about the regulatory role of miRNAs in the immune response to T. pallidum infection. Here, we analyze the differential expression of miRNAs in peripheral blood mononuclear cells (PBMCs) between secondary syphilis (SS) patients and healthy controls and study the correlation between miRNAs expression and clinical features with bioinformatics.
Project description:Treponema pallidum (Tp) infection evokes vigorous immune responses, resulting in tissue damage. The immune mechanism after Treponema pallidum infection is still not clear. MicroRNAs (miRNAs) have been shown, however, to influence immune cell function and consequently the generation of antibody responses during other microbe infections, but these values are unknown for Tp. In this study, we performed a comprehensive analysis of differentially expressed miRNAs in healthy persons, untreated patients with syphilis, patients in the serofast state, and serologically cured patients. MiRNAs were profiled from patient peripheral blood obtained at the time of serological diagnosis. There were 89 differentially regulated miRNA identified in total. Then both the target sequence analysis on these different miRNAs and pathway analysis were performed to identify important immune and cell signaling pathways. Following RT-qPCR confirmation, three miRNAs (hsa-miR-195-5p, hsa-miR-223-3p, hsa-miR-589-3p) showed significant difference among serofast state, and serological cure (P<0.05). Two miRNAs (hsa-miR-195-5p, hsa-miR-1204) showed significant differences among untreated patients and healthy individuals. This is the first study of miRNA expression difference in PBMC in different stages of T. pallium infection. Our study suggests that the combination of three miRNAs has great potential to serve as non-invasive biomarkers of Treponema pallidum infections, which will facilitate better diagnosis and treat of T. pallium infections.
Project description:We performed a comprehensive miRNA profiling analysis of exosomes by Treponema pallidum-stimulated microarrays. A total of 2×106 macrophages were obtained by THP-1 differentiation and grown in RPMI-1640 containing 10% exosome-free FBS. Exosomes were acquired from macrophage culture supernatants with (n = 7) or without (n = 3) T. pallidum. Briefly, macrophages were washed in PBS twice and further grown in fresh medium for 12 h (n = 2), 24 h (n = 2) and 48 h (n = 3) to collect exosomes. Exosomal miRNA microarray assays were carried out with Agilent Human miRNA (8*60K) array.