Mitochondrial NLRX1 is a member of the family of nucleotide-binding domain and leucine-rich-repeat-containing proteins (NLRs) that mediate host innate immunity as intracellular surveillance sensors against common molecular patterns of invading pathogens.
A well-described feature of mammalian innate responses to microorganisms involves recognition of common molecular patterns, such as lipopolysaccharide and peptidoglycan, and subsequent activation of the NF-κB transcription factor pathway.
Although purified b-glucan acts as a potent adjuvant for the induction of IL-23 producing DCs and TH-17 priming [26], the structural complexity and differential cellular composition of various fungi makes it difficult to predict whether, which, and how common molecular patterns in cell wall of different fungi link innate sensing by DCs with TH-17 pathway induction.
Despite being symbiotically important, these molecules, as common microbe-associated molecular patterns (MAMPs) of the rhizobial bacteria, may also trigger defense responses upon recognition by the cognate host pattern recognition receptors (PRRs) and thus are possibly associated with symbiosis specificity.
In 2014, Kusuda et al. reported that serum KD-specific molecules were mostly derived from biofilms and possessed molecular structures common to microbe-associated molecular patterns from Bacillus cereus, Bacillus subtilis, YPT and Staphylococcus aureus.
TLRs respond to molecular patterns such as unmethylated CpG dinucleotides that are common in bacteria but uncommon in the host.
Since most innate immune responses, especially those to pathogen-associated molecular patterns, are evolutionary conserved, it is likely that such common responses can be found.
These mechanisms include a basal defence response following the recognition of common microbial features, known as pathogen-associated molecular patterns or microbe-associated molecular patterns.
TLRs are a class of highly conserved pattern recognition receptors found in metazoan species that respond to conserved molecular patterns (also referred to as pathogen-associated molecular patterns or PAMPs) common to microbial pathogens [1], [2].
Upon binding to pathogen-associated molecular patterns (PAMPs), SP-A and SP-D enhance the opsonophagocytosis of common respiratory pathogens by macrophages [ 5, 6].
