Nucleotide-Binding Oligomerization Domain-Like Receptors: Intracellular Pattern Recognition Molecules for Pathogen Detection and Host Defense

University of Michigan, Ann Arbor, Michigan, United States
The Journal of Immunology (Impact Factor: 4.92). 10/2006; 177(6):3507-13. DOI: 10.4049/jimmunol.177.6.3507
Source: PubMed


The nucleotide binding oligomerization domain-like receptor (NLR) family of pattern recognition molecules is involved in a diverse array of processes required for host immune responses against invading pathogens. Unlike TLRs that mediate extracellular recognition of microbes, several NLRs sense pathogens in the cytosol and upon activation induce host defense signaling pathways. Although TLRs and NLRs differ in their mode of pathogen recognition and function, they share similar domains for microbial sensing and cooperate to elicit immune responses against the pathogen. Genetic variation in several NLR genes is associated with the development of inflammatory disorders or increased susceptibility to microbial infection. Further understanding of NLRs should provide critical insight into the mechanisms of host defense and the pathogenesis of inflammatory diseases.

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    • "This is mediated through the detection of pathogen-associated (PAMPs) and danger-associated molecular patterns (DAMPs) by receptors termed pattern-recognition receptors (PRRs) expressed in alveolar macrophages , dendritic cells, and epithelial cells [20]. The PRRs include transmembrane Toll-like receptors (TLRs) cytosolic NOD-like receptors (NLRs) and RIG-I-like receptors (RLRs) [21]. Activation 1043-4666/Ó 2015 Elsevier Ltd. "
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    • "The NLRC4 inflammasome responds to gram-negative bacterial components such as flagellin and basal body Rod proteins present in bacterial type III secretion systems [23, 24, 49]. Consequently, intracellular pathogens expressing these factors, such as Salmonella typhimurium, Shigella flexneri, Pseudomonas aeruginosa, Burkholderia thailandensis, and Legionella pneumophila can activate the NLRC4 inflammasome [15, 23, 24, 26, 50, 51]. In the present work, it was employed the gram-negative bacterium L. pneumophila to study the effect of propolis on NLRC4 inflammasome. "
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