Do NK cells express NKG2D?
NKG2D, encoded by Klrk1, is an activating cell surface receptor that is predominantly expressed on cytotoxic immune cells. NKG2D is abundantly present on all NK cells, NKT cells, and subsets of γδ T cells.
Do mice have NK cells?
In C57BL/6 mice, NK cells are identified by the presence of NK1. 1 (NKR-P1C) and NCR1 (NKp46/CD335), as well as CD49b (DX5, Integrin VLA-2α), are common NK cell markers in other mouse backgrounds (19, 20). NK cells are most similar to a group of lymphocytes known as innate lymphoid cells (ILCs) (21).
What is NKG2D receptor?
NKG2D is an activating receptor (transmembrane protein) belonging to the NKG2 family of C-type lectin-like receptors. NKG2D is encoded by KLRK1 (killer cell lectin like receptor K1) gene which is located in the NK-gene complex (NKC) situated on chromosome 6 in mice and chromosome 12 in humans.
What is NKG2D ligand?
The Natural Killer Group 2D (NKG2D) receptor plays an important role in protecting the host from infections and cancer. By recognizing ligands induced on infected or tumor cells, NKG2D modulates lymphocyte activation and promotes immunity to eliminate ligand-expressing cells.
What does NKG2D bind to?
The activating receptor NKG2D can directly bind to a diverse family of ligand molecules expressed on the surface of tumor cells. In NK cells, NKG2D interacts with either DAP10 (both human and mouse) or DAP12 (mouse only) and induces cytotoxicity and IFN-γ production.
What is the role of perforin?
Perforin is a glycoprotein responsible for pore formation in cell membranes of target cells. Perforin is able to polymerize and form a channel in target cell membrane. Natural killer (NK) cells and CD8-positive T-cells are the main source of perforin.
What cytokines do NK cells produce?
Activated NK cells secrete a wide variety of cytokines such as IFN-γ, TNF-α, GM-CSF, IL-10, IL-5, and IL-13 and chemokines such as MIP-1α, MIP-1β, IL-8, and RANTES (94–96).
What cytokines activate NK cells?
IL-12 is the prototypical innate cytokine capable of activating NK cells, and it acts synergistically with several other cytokines to elicit the production of IFN-γ.
What is the natural killer cell?
A type of immune cell that has granules (small particles) with enzymes that can kill tumor cells or cells infected with a virus. A natural killer cell is a type of white blood cell. Also called NK cell and NK-LGL.
What is HLA E?
HLA-E is an important modulator of natural killer (NK) and cytotoxic T lymphocyte (CTL) activation and inhibitory function and is the best studied of the nonclassical HLA molecules (Pietra et al., 2009). HLA-E has a role in both the innate and adaptive immune responses.
Is perforin a cytokine?
Preformed perforin granules predominate in unstimulated cells, which are not producing cytokines.
How is perforin secreted?
Secretion of granzymes and perforin across the synapse facilitates NK cell cytolysis (2, 3). Within NK cells, perforin and granzymes are packaged inside lytic granules with serglycin, which neutralizes their cytolytic activity (4, 5). Other molecules are also secreted at synapses within vesicles (7).
Why does IL-21 not inhibit NKG2D in mice?
In mice, IL-21 stimulation of murine NK cells does not regulate NKG2D expression, and this may be due to the pairing of NKG2D with DAP12 in NK cells, which may not be regulated by IL-21 ( 21 ). Similarly, TGF-β decreases NKG2D expression, but this can be reversed after NK cells are exposed to IL-2 or IL-18 ( 24 ).
What is the role of the NKG2D receptor?
The Natural Killer Group 2D (NKG2D) receptor plays an important role in protecting the host from infections and cancer. By recognizing ligands induced on infected or tumor cells, NKG2D modulates lymphocyte activation and promotes immunity to eliminate ligand-expressing cells.
Where are NKG2D ligands found in the pancreas?
Expression of NKG2D ligands and self-reactivity. NKG2D ligands have been detected on the pancreatic islets of pre-diabetic NOD mice, but age-matched BALB/c mice did not express Rae1 or other NKG2D ligands ( 75 ). Thus, the role of NKG2D in the development of type I diabetes (T1D) mellitus may be NOD strain-specific.