Toll-like receptors (TLR) are key components of innate immune system. As TLR activation could induce potentially harmful inflammatory response, activation of TLR signaling pathways has to be under tight control. Besides other control mechanisms, an inhibitory function of murine TLR4 splice variants was recently demonstrated. In this study we investigated expression of four TLR4 splice variants in human antigen presenting cells (APC). Furthermore, we studied modification in TLR4 splice variants expression in APC in cystic fibrosis (CF) patients chronically infected by Gram-negative bacteria. We developed a novel reliable real-time PCR detection system that allowed monitoring of individual TLR4 splice variants expression. In APC from healthy donors we detected a characteristic transient increase of two out of four splice variants after lipopolysaccharide (LPS) stimulation. Similarly to murine TLR4, one of these variants, NM 003266, might translate to a potentially inhibitory protein. In contrast to controls, CF monocytes had significantly changed LPS-induced expression of TLR4 gene and its variants including reduced ability to up-regulate the expression of the potentially inhibitory variant upon stimulation. In accordance with this observation, monocytes from CF patients produced significantly more tumor necrosis factor after LPS stimulation than healthy controls. Our results thus describe the kinetics of TLR4 splicing variants expression after LPS stimulation and indicate a possible alteration of its regulation in CF patients.
- MeSH
- Alternative Splicing MeSH
- Antigen-Presenting Cells chemistry immunology MeSH
- Cystic Fibrosis immunology MeSH
- Dendritic Cells immunology MeSH
- Adult MeSH
- Financing, Organized MeSH
- Cells, Cultured MeSH
- Humans MeSH
- Lipopolysaccharides immunology MeSH
- RNA, Messenger analysis MeSH
- Monocytes immunology MeSH
- Reverse Transcriptase Polymerase Chain Reaction methods MeSH
- Gene Expression Regulation MeSH
- Gene Expression Profiling MeSH
- Tumor Necrosis Factor-alpha biosynthesis MeSH
- Toll-Like Receptor 4 biosynthesis genetics MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
