TERM	DEFINITION
POLYCYCLIC AROMATIC HYDROCARBON	A group of >100 substances that are formed during burning of coal, tobacco, oil, gas, garbage and also during grilling of meats.
HYALURONIC ACID	A component of the extracellular matrix that is capable of effecting cell migration and proliferation. Hyaluronic acid can bind to CD44 and its degradation products can activate TLRs.
CD44	CD44 is expressed on multiple cell types including white and red blood cells. Its ligands include hyaluronate, osteopontin, and fibronectin.
CD14	CD14 is the LPS receptor and mediates Toll Receptor Like (TLR)-4 signaling. CD14 is expressed on momocytes, macrophages and neutrophils.
INFLAMMASOME	The inflammasome is a multimeric protein complex activated by the innate immune system via DAMPs and PAMPs to ultimately cleave pro-IL-1b to IL-1b and pro-IL-18 to IL- 18. Specific components of the inflammasome can vary based on the initiating signal but nod like receptors (NLRs) are critical components.
N-ACETYL-CYSTEINE	Acts as an anti-oxidant to counter the effects of diesel exhaust particles. NAC can decrease bronchial hyperreactivity and alter miRNA expression induced by diesel exhaust exposure.
MyD88	MyD88 is an essential component of TLR signals. All TLRs except TLR3 use MyD88 as an adaptor molecule that precedes the activation of IRAK and TRAF6, ultimately leading to NFkb or AP-1 mediated gene transcription. MyD88 deficient mice have decreased autoimmunity .
LINE-1 (Long Interspersed Elements)	The only complete retrotransposon in the human genome, LINE-1 is 6kB in length, contains 2 open reading frames, and exists at about 516,000 copies. Retrotransposons are “genomic parasites”, represent 17% of the human genome, and can induce spontaneous genetic diseases when they become mobile.
Danger Associated Molecular Pattern (DAMP) Pathogen Associated Molecular Pattern (PAMP)	DAMPs and PAMPs are recognized by pattern recognition receptors such as Toll Receptors (TLRs). PAMPs are exogenous or endogenous but DAMPs are almost all endogenous molecules. TLR4 binds ipopolysaccharide from gram negative bacteria, heat shock protein 6, and RSV protein F. TLR7 and 8 bind single stranded RNA and are important for anti-viral defense.
IL-33	IL-33 is an IL-1 family member that is produced by epithelial cells, smooth muscle cells and fibroblasts and increases IL-5 and IL-13 production.
IL-18	IL-18 has effects similar to IL-12 and induces IFNg production. Production of an IL-18 binding protein by some viruses such as molluscum contagiosum allows evasion of the immune system.