Figure 1.

Overview of the mechanisms of activation of various nucleotide-binding and oligomerization domain (NOD)-like receptors (NLR) and non-NLR inflammasomes in response to microbes, resulting in an inflammatory response via secretion of activated proinflammatory cytokines and pyroptosis. Steps in inflammasome activation: 1) Priming step involving factors such as Toll-like receptors (TLRs), NOD1, and NOD2; 2) inflammasome activation step. Mechanisms for activation of NLRP3 inflammasome: a) K⁺ efflux, b) lysosomal rupture, and c) mitochondrial reactive oxygen species (ROS) generation. A. fumigatus = Aspergillus fumigatus; AIM2 = absent in melanoma 2; ASC = apoptosis-associated speck-like protein; BIR = baculovirus inhibitor of apoptosis protein; B. pseudomallei = Burkholderia pseudomallei; CARD = caspase recruitment domain; C. neoformans = Cryptococcus neoformans; E. coli = Escherichia coli; FIIND = function to find domain; F. tularensis = Francisella tularensis; HIN200 = hematopoietic expression, interferon-inducible nature, and nuclear localization domain 200; K. pneumoniae = Klebsiella pneumoniae; L. monocytogenes = Listeria monocytogenes; L. pneumophila = Legionella pneumophila; LRR = leucine-rich repeat; M. catarrhalis = Moraxella catarrhalis; MDP = muramyl dipeptide; M. tuberculosis = Mycobacterium tuberculosis; NACHT = NAIP, CIITA (class II major histocompatibility complex transactivator), HET-E (incompatibility locus protein from Podospora anserine), and TP1 (mammalian telomerase-associated protein 1); NAIP = NLR family apoptosis inhibitory protein; NF-κB = nuclear factor-κB; P. aeruginosa = Pseudomonas aeruginosa; P. brasiliensis = Paracoccidioides brasiliensis; PYD = pyrin domain; RIP2 = receptor-interacting serine/threonine-protein kinase 2; S. aureus = Staphylococcus aureus; S. pneumoniae = Streptococcus pneumoniae; SS = secretion system; Y. pestis = Yersinia pestis.