Includes mRNA and virus

Includes methylated CpGs

Includes the LPS cell wall of gram-negative bacteria

Includes nuclear proteins or nucleic acids found outside the nucleus such as extracellular HMGB1

Humoral immunity is mediated by B lymphocytes

Humoral immunity is mediated by T lymphocytes

Antibody production is a feature of cell-mediated immunity

Cytokine-activated phagocytosis is not a feature of cell-mediated immunity

There are 10 different functional TLRs in humans labelled TLR1-TLR10

The High mobility group box (HMGB1) DNA-binding proteins bind to TLR2

TLRs are integral membrane proteins with cysteine-rich repeat motifs flanked by leucine-rich motifs in their extracellular region

TLRs were discovered in Drosophila

Not all NOD-like receptors (NLRs) originate from a nucleotide oligomerization Domain.

NOD2 is highly expressed in the brain

Both NOD1 and NOD2 contain the baculovirus IAP repeat domain in their typical domain structure

NOD1 recognizes protein components derived from gram negative and gram positive peptidoglycans

NOD-like receptors

Cytosolic DNA sensors

Transcription factor NF-kB

Retinoic-acid inducible gene (RIG)-like receptors (RLRs)

C5b

C5b9

C3a

C3b

RLRs can recognize ds RNA and RNA-DNA complexes

RLRs include RIG-1 and MDA5 receptors

RLRs are only expressed in bone marrow derived leukocytes

Coronavirus can evade RIG-1 and MDA5

Cytosolic DNA sensors

RIG-like receptors

Collectins

NOD-like receptors

The complement system is a cell-associated PRR

The complement system is a soluble PRR

RLRs are present in the cytosol of phagocytes and other cells.

The TLRs are specific to the plasma membrane and endosomal membranes