Pilot Study On Proinflammatory Effect And Its Mechanism Of Treponema Pallidum Outer Membrane Protein Tp92

we choose macrophages and HMEC-1 cells which play an important role in innate immunity and early syphilis as target cells, and wish to explore the cellular signal transduction pathways of Tp92. The study will help reveal the pathogenic mechanism of syphilis, and provide theretical and practical basis for treatment of syphilis-related diseases. We used Tp92 infected target cells, and ELISA detected the secretion levels of TNF-α, IL-1β and IL-6 in supernatant of culture medium; After preliminarily explore the proinflammatory effect of Tp92 on target cells, We blocked My D88/ NF-κB, MAPKs/ p38 and NLRP3/ Caspase-1 pathways by PDTC, SB202190 and Z-YVAD-FMK respectively, and then detected the secretion levels of proinflammatory cytokines, the expression levels of key molecules of pathways and the enzyme activity of LDH. The experimental results are as follows. Different concentrations of Tp92 protein can significantly induced secretion of TNF-α, IL-1β and IL-6 in target cells. When 5μg/m L of Tp92 protein stimulated target cells for 6h, the secretion levels of TNF-α and IL-6 reached their peaks, and the secretion levels of IL-1β arrived at 12h; After blockade of My D88/ NF-κB and MAPKs/ p38 pathways, all results showed that the secretion levels of proinflammatory cytokines and the enzyme activity of LDH have no significant difference(P > 0.05); After blockade of NLRP3/ Caspase-1 pathways, the secretion levels of TNF-α, IL-6 and IL-1β and the enzyme activity of LDH showed a significant decrease(P < 0.05), and the expression levels of caspase-1 and NLRP3 also have a significant decline. The results suggest that Recombinant Tp92 protein can promote macrophages and HMEC-1 cells to secrete proinflammatory cytokines TNF-α, IL-1β and IL-6, and the inflammation that induced by recombinant Tp92 protein in macrophages and HMEC-1 cells may be mediated by NLRP3/ Caspase-1 pathway.