Innate Immunity: Inflammation I - Vocabulary Flashcards

Vocabulary flashcards covering innate immunity concepts, PRRs, PAMPs/DAMPs, and signaling pathways from the lecture notes.

Innate immunity

The non-specific first line of defense against microbes; acts quickly and shapes adaptive immunity.

First line of defense

Immediate, non-specific barriers and responses that prevent infection.

PAMPs

Pathogen-Associated Molecular Patterns recognized by PRRs; microbial structures essential for survival.

MAMPs

Microbe-Associated Molecular Patterns; similar to PAMPs, recognized by PRRs.

DAMPs

Damage-Associated Molecular Patterns released by injured or necrotic cells, triggering inflammation.

PRR

Pattern Recognition Receptor; germline-encoded receptors that detect PAMPs/DAMPs.

TLR

Toll-like receptor; a PRR recognizing PAMPs; located on cell surface or in endosomes; signals via adaptors.

NLR

NOD-like receptor; cytosolic PRR detecting intracellular PAMPs/DAMPs and activating NF-κB and cytokines.

RLR

RIG-I-like receptor; cytosolic PRR that detects viral RNA and induces NF-κB and type I interferons.

MyD88

Adaptor protein used by most TLRs to propagate signaling to NF-κB.

TRIF

TIR-domain-containing adaptor inducing IFN-β; adaptor for TLR3 and TLR4 signaling leading to IRF-3 and type I IFN.

TRAM

TRIF-related adaptor molecule; participates in TLR4 signaling to TRIF.

NF-κB

Nuclear factor kappa B; transcription factor driving expression of pro-inflammatory cytokines.

IRF-3

Interferon regulatory factor 3; transcription factor promoting type I interferon production.

LPS

Lipopolysaccharide; endotoxin from Gram-negative bacteria recognized by TLR4.

Peptidoglycan

Bacterial cell wall polymer recognized by TLR2 and NOD1/2.

Lipoteichoic acid

Teichoic acids in Gram-positive bacteria recognized by TLR2.

Flagellin

Protein subunit of bacterial flagella recognized by TLR5.

Zymosan

Fungal cell wall component recognized by PRRs such as Dectin-1 and TLR2.

Dectin-1

C-type lectin receptor recognizing beta-glucans in fungi; cooperates with other PRRs.

CD14

Co-receptor that assists TLR4 in recognizing LPS on macrophages.

Mannose receptor (MR, CD206)

C-type lectin receptor that binds mannose/fucose residues to promote phagocytosis.

Endosome

Intracellular vesicle where TLR3, TLR7, and TLR9 reside to detect nucleic acids.

CpG DNA

Unmethylated CpG motifs recognized by TLR9.

dsRNA

Double-stranded RNA recognized by TLR3 in endosomes.

ssRNA

Single-stranded RNA recognized by TLR7 (and TLR8) in endosomes.

TLR1

TLR that forms heterodimers with TLR2 to recognize triacylated lipoproteins.

TLR2

TLR recognizing lipoproteins; forms heterodimers with TLR1 or TLR6.

TLR4

TLR recognizing LPS on the cell surface; signals via MyD88 and TRIF.

TLR5

TLR recognizing flagellin.

TLR6

TLR forming heterodimers with TLR2 to recognize diacylated lipoproteins.

NOD1

Cytosolic NLR recognizing peptidoglycan motifs; activates NF-κB.

NOD2

Cytosolic NLR recognizing muramyl dipeptide; activates NF-κB.

RIG-I

RLR detecting viral RNA in the cytosol; activates NF-κB and IRF-3.

HMGB1

High mobility group box 1; a DAMP released by necrotic cells that promotes inflammation.

Uric acid

Metabolite that can act as a DAMP when released by damaged cells.

Heat-shock proteins

Chaperone proteins that can function as DAMPs when released extracellularly.

Inflammasome

Multiprotein complex that activates caspase-1, enabling maturation of IL-1β and IL-18.

Caspase-1

Protease that cleaves pro-IL-1β and pro-IL-18 into active cytokines.

IL-1β

Pro-inflammatory cytokine produced in response to PRR signaling.

IL-18

Pro-inflammatory cytokine activated by caspase-1 during inflammasome signaling.

Proinflammatory cytokines

Cytokines such as IL-1, IL-6, IL-8, IL-18, and TNF-α produced during inflammation.

Chemokines

Chemotactic cytokines (e.g., CXCL8/IL-8, CXCL10, CCL3/4/5) that recruit immune cells.

Prostaglandins

Lipid mediators derived from arachidonic acid that promote inflammation and fever.

Leukotrienes

Lipid mediators contributing to inflammation and bronchoconstriction.

Platelet-activating factor (PAF)

Lipid mediator promoting platelet aggregation and inflammatory responses.

Macrophage

Phagocytic innate immune cell that orchestrates inflammation and antigen presentation.

Neutrophil

Rapidly recruited phagocyte that responds early to infection and inflammation.