Immune receptor
Encyclopedia
An immune receptor is a receptor
, usually on a cell membrane
, which binds to a substance (for example, a cytokine
) and causes a response in the immune system
.
are pattern recognition receptors (PRRs), Toll-like receptor
s (TLRs), killer activated and killer inhibitor receptors (KARs and KIRs), complement receptor
s, Fc receptors, B cell receptors and T cell receptor
s.
Receptor (biochemistry)
In biochemistry, a receptor is a molecule found on the surface of a cell, which receives specific chemical signals from neighbouring cells or the wider environment within an organism...
, usually on a cell membrane
Cell membrane
The cell membrane or plasma membrane is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. It basically protects the cell...
, which binds to a substance (for example, a cytokine
Cytokine
Cytokines are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication...
) and causes a response in the immune system
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...
.
Types
The main receptors in the immune systemImmune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...
are pattern recognition receptors (PRRs), Toll-like receptor
Toll-like receptor
Toll-like receptors are a class of proteins that play a key role in the innate immune system. They are single, membrane-spanning, non-catalytic receptors that recognize structurally conserved molecules derived from microbes...
s (TLRs), killer activated and killer inhibitor receptors (KARs and KIRs), complement receptor
Complement receptor
A complement receptor is a receptor of the complement system, a part of the mediated innate immune system. Complement receptors are responsible for detecting pathogens by mechanisms not mediated by antibodies. Complement activity is not antigen sensitive, but can be triggered by specific antigens...
s, Fc receptors, B cell receptors and T cell receptor
T cell receptor
The T cell receptor or TCR is a molecule found on the surface of T lymphocytes that is responsible for recognizing antigens bound to major histocompatibility complex molecules...
s.
| Receptor | Bind to | Function |
|---|---|---|
| pattern recognition receptors (PRRs) (e.g. TLRs Toll-like receptor Toll-like receptors are a class of proteins that play a key role in the innate immune system. They are single, membrane-spanning, non-catalytic receptors that recognize structurally conserved molecules derived from microbes... , NLRs) |
pathogen-associated molecular pattern Pathogen-associated molecular pattern Pathogen-associated molecular patterns, or PAMPs, are molecules associated with groups of pathogens, that are recognized by cells of the innate immune system. These molecules can be referred to as small molecular motifs conserved within a class of microbes... s (PAMP) |
Mediate cytokine production --> inflammation Inflammation Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process... --> destroying pathogen |
| killer activated and killer inhibitor receptors (KARs and KIRs) | Avails NK cells to identify abnormal host cells (KAR) or inhibit inappropriate host cell destruction (KIR) | |
| complement receptor Complement receptor A complement receptor is a receptor of the complement system, a part of the mediated innate immune system. Complement receptors are responsible for detecting pathogens by mechanisms not mediated by antibodies. Complement activity is not antigen sensitive, but can be triggered by specific antigens... s |
complement proteins on e.g. microbes | Allow phagocytic and B cells to recognize microbes and immune complexes |
| Fc receptors | epitope Epitope An epitope, also known as antigenic determinant, is the part of an antigen that is recognized by the immune system, specifically by antibodies, B cells, or T cells. The part of an antibody that recognizes the epitope is called a paratope... -antibody complexes |
Stimulate phagocytosis |
| B cell receptors | epitope Epitope An epitope, also known as antigenic determinant, is the part of an antigen that is recognized by the immune system, specifically by antibodies, B cells, or T cells. The part of an antibody that recognizes the epitope is called a paratope... s |
B cell differentiation into plasma cells and proliferation |
| T cell receptor T cell receptor The T cell receptor or TCR is a molecule found on the surface of T lymphocytes that is responsible for recognizing antigens bound to major histocompatibility complex molecules... s |
linear epitopes bound to MHC Major histocompatibility complex Major histocompatibility complex is a cell surface molecule encoded by a large gene family in all vertebrates. MHC molecules mediate interactions of leukocytes, also called white blood cells , which are immune cells, with other leukocytes or body cells... |
Activate T cells |
| Cytokine receptor Cytokine receptor Cytokine receptors are receptors that bind cytokines.In recent years, the cytokine receptors have come to demand the attention of more investigators than cytokines themselves, partly because of their remarkable characteristics, and partly because a deficiency of cytokine receptors has now been... s |
cytokine Cytokine Cytokines are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication... s |
regulation and co-ordination of immune responses |