ID immunology glossary P-R

Pathogen associated molecular patterns

The antigen‐binding site of an antibody composed of portions of the different CDRs (HVR) of the antibody's heavy and light chain variable domains, also TCR

A germline‐encoded receptor that recognizes unique and essential structures that are present in microorganisms, but absent from the host. In vertebrates, signalling through these receptors leads to the production of pro‐inflammatory cytokines and chemokines and to the expression of co‐stimulatory molecules by antigen‐presenting cells

Cell wall component of Gram‐positive bacteria

Protein released by cytotoxic T cells and NK cells thainduces apoptosis

aka tissue‐specific antigens. Proteins that are restricted in their expression to specific tissues in the periphery. To induce and maintain T cell tolerance to these proteins, they are expressed by non‐haematopoietic cells in the thymus and secondary lymphoid organs

Secondary lymphoid organs present in the small intestine (mostly in the ileum). They occur on the intestinal wall, opposite the line of attachment of the mesentery, the antimesenteric border. Peyer's patches consist of a dome area, B cell follicles and interfollicular T cell areas. High endothelial venules are present mainly in the interfollicular areas

Prostaglandin G/H synthase

The ingestion or engulfment of particles by cells

An intracellular vacuole containing material ingested byphagocytosis

The morphologic characteristics of a cell or animal resulting from genetic expression

Evolutionary development and history of species

Lymphocyte derived from a B cell that produces antibodies

A dendritic cell (DC) subset with a morphology that resembles that of a plasmablast. Plasmacytoid DCs produce large amounts of type I interferons in response to viral infection

A phagocytic cells associated with innate immunity in invertebrates (arthropods)

A term that describes the products of a number of different cell types (cf. monoclonal)

Any antibody that comprises 2 or more 4 chain structures (H & L chains). Includes IgM and IgA

An enzyme that triggers melanisation after activation. The pro form is activated by a number of factors from bacteria and fungi

Pattern recognition receptors

nucleotide sequence that is part of the genome of an organism that appears to code for a gene product (typically a protein) but does not (or no longer does so)

Recombination Activation Gene, RAG1 and RAG2, recombinases involved in VDJ and VJ gene segment joining

Regulated on activation, normal T expressed and secreted

Various reactive oxygen species, including superoxideanions produced by phagocytes via the activation of theNADPH oxidase enzymatic system, and other compounds derived from superoxide anion metabolism,such as hydrogen peroxide and hydroxyl radicals. Crucial for the antimicrobial activity of neutrophils

The process describing the cutting and re‐splicing of immunoglobulin (and TCR) gene segments making up the variable regions. Is restricted to influencing the CDR3 region of the final protein product, involves RAGs

A subset of T cells that control the activity of effector T cells under inflammatory or steady state conditions

Lipid mediators that are induced in the resolution phase following acute inflammation. They are synthesized from the essential omega‐3 fatty acids eicosapentaenoic acid and docosahexaenoic acid

Reactive oxygen species, e.g., hydrogen peroxide