Immune System Overview

A set of flashcards covering key concepts related to the immune system, focusing on various types of immunity, immune responses, and specific functions and molecules involved.

Intrinsic immunity

Early, rapid, non-specific response at the cell level; all cells can respond.

Innate immunity

Early, rapid, non-specific response involving specialized immune cells at the tissue level.

Adaptive immunity

Slower, antigen-specific response with long-lived memory.

Order of immune activation

Intrinsic → Innate → Adaptive.

Pattern recognition receptors (PRRs)

Host receptors that detect pathogen-associated molecular patterns.

PAMPs

Non-self molecules detected by PRRs.

DAMPs

Host molecules released during cellular damage.

Three intrinsic immune sensors

TLRs, RLRs, cGAS.

PRR transcription factors

IRF3, IRF7, NF-κB.

PRR outcome

Type I interferon production (IFN-α, IFN-β).

TLR3

Detects dsRNA.

TLR7/8

Detect ssRNA.

TLR9

Detects unmethylated CpG DNA.

RIG-I

Detects short RNA.

MDA5

Detects long RNA.

MAVS

RLR signaling protein.

cGAS

Detects cytoplasmic DNA.

cGAMP

Activates STING.

Apoptosis

Non-inflammatory cell death.

Necroptosis

Inflammatory cell death.

ZBP1

Detects Z-nucleic acids.

Type I IFN

IFN-α, IFN-β.

ISGs

Genes that create an antiviral state.

Macrophages

Phagocytose pathogens.

Dendritic cells

Activate CD4+ T cells.

NK cells

Kill cells lacking MHC I.

RNA interference

Destroys viral RNA.

CRISPR

Bacterial antiviral defense.