Streptococcus pneumoniae Production and Increased Susceptibility to Pathways Underlies Decreased Cytokine Activity in TLR2, but Not TLR4, Signaling Complete Dependence on IRAK4 Kinase

Production and Increased Susceptibility to Pathways Underlies Decreased Cytokine Activity in TLR2, but Not TLR4, Signaling Complete Dependence on IRAK4 Kinase

Streptococcus pneumoniae Endopeptidase O (PepO) Elicits a Strong Innate Immune Response in Mice via TLR2 and TLR4 Signaling Pathways

Interaction between virulence factors of Streptococcus pneumoniae and innate immune receptors elicits host responses through specific signaling pathways during infection. Insights into the signaling events may provide a better knowledge of the starting events for host-pathogen interaction. Here we demonstrated a significant induction of innate immune response elicited by recombinant S. pneumoni...

Low pH Environmental Stress Inhibits LPS and LTA-Stimulated Proinflammatory Cytokine Production in Rat Alveolar Macrophages

Gastric aspiration increases the risks for developing secondary bacterial pneumonia. Cytokine elaboration through pathogen recognition receptors (PRRs) is an important mechanism in initiating innate immune host response. Effects of low pH stress, a critical component of aspiration pathogenesis, on the PRR pathways were examined, specifically toll-like receptor-2 (TLR2) and TLR4, using isolated ...

TLR4 Mediates Pneumolysin-Induced ATF3 Expression through the JNK/p38 Pathway in Streptococcus pneumoniae-Infected RAW 264.7 Cells

Activating transcription factor-3 (ATF3) acts as a negative regulator of cytokine production during Gram-negative bacterial infection. A recent study reported that ATF3 provides protection from Streptococcus pneumoniae infection by activating cytokines. However, the mechanism by which S. pneumoniae induces ATF3 after infection is still unknown. In this study, we show that ATF3 was upregulated v...

TLR2 and TLR4 Signaling Pathways and Gastric Cancer: Insights from Transcriptomics and Sample Validation

Background: Pattern recognition receptors, especially toll-like receptors (TLRs), as the first line of defense for pathogen detection, were found to be associated with H.­ pylori infection and gastric cancer (GC). However, the expression levels of TLRs, i.e. TLR2 and TLR4, as the main receptors sensed by H.­ pylori, still remain largely ambiguous. We aimed to investigate the patterns of key tra...