ABSTRACT
The fungus Trichophyton schoenleinii (T. schoenleinii) is the causative agent of Trichophytosis and Tinea favosa of the scalp in certain regions of Eurasia and Africa. Human innate immune system plays an important role in combating with various pathogens including fungi. The inflammasome is one of the most critical arms of host innate immunity, which is a protein complex controlling maturation of IL-1β. To clarify whether T. schoenleinii is able to activate the inflammasome, we analyzed human monocytic cell line THP-1 for IL-1β production upon infection with T. schoenleinii strain isolated from Tinea favosa patients, and rapid IL-1β secretion from THP-1 cells was observed. Moreover, applying competitive inhibitors and gene specific silencing with shRNA, we found that T. schoenleinii induced IL-1β secretion, ASC pyroptosome formation as well as caspase-1 activation were all dependent on NLRP3. Cathepsin B activity, ROS production and K⁺ efflux were required for the inflammasome activation by T. schoenleinii. Our data thus reveal that the NLRP3 inflammasome plays an important role in host defense against T. schoenleinii, and suggest that manipulating NLRP3 signaling can be a novel approach for control of diseases caused by T. schoenleinii infection.
Subject(s)
Animals , Humans , Mice , Bone Marrow Cells , Cell Biology , Carrier Proteins , Metabolism , Caspase 1 , Metabolism , Cell Line , Dendritic Cells , Cell Biology , Metabolism , Microbiology , Enzyme Activation , Hot Temperature , Inflammasomes , Metabolism , Interleukin-1beta , Metabolism , Lysosomes , Metabolism , Monocytes , Cell Biology , Metabolism , Microbiology , NLR Family, Pyrin Domain-Containing 3 Protein , Potassium , Metabolism , Reactive Oxygen Species , Metabolism , Signal Transduction , Trichophyton , PhysiologyABSTRACT
The complete nucleotide sequence of a cDNA clone encoding weever ribosomal protein L8, WeevL8, is described here. The WeevL8 cDNA has 848 nucleotides in full length and encodes a 257 amino-acid protein with a calculated molecular mass of 28.02 kDa. Two conserved domains have been identified in WEEVL8. It was concluded fromsequence alignment that WeevL8 gene was quite conservative, consistent with its role as a house-keeping gene. A phylogenetic analysis made by L8 protein showed the similar phylogenetic relationship to that with 18s rDNA. The high similarity supports the notion that ribosomal protein L8 can also be used as phylogenetic criterion.