Leukocyte immunoglobulin-like receptors
Encyclopedia
The leukocyte immunoglobulin-like receptors (LILR) are a family
of receptors
possessing extracellular immunoglobulin domains.
They are also known as CD85
, ILTs and LIR, and can exert immunomodulatory effects on a wide range of immune cells. The human genes encoding these receptors are found in a gene cluster
at chromosomal region 19q13.4.
They include
A subset of LILR recognise MHC class I
(also known as HLA
class I in humans). Of these, the inhibitory receptors LILRB1
and LILRB2
show a broad specificity for classical and non-classical MHC alleles with preferential binding to b2m
-associated complexes. In contrast, the activating receptors LILRA1 and LILRA3
prefer b2m-independent free heavy chains of MHC class I, and in particular HLA-C
alleles.
Protein family
A protein family is a group of evolutionarily-related proteins, and is often nearly synonymous with gene family. The term protein family should not be confused with family as it is used in taxonomy....
of receptors
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...
possessing extracellular immunoglobulin domains.
They are also known as CD85
CD85
The term "CD85" was originally used to refer to LILR1 which is now known as CD85j, however there are a number of CD85 genes: LILR: leukocyte immunoglobulin-like receptor; ILT: immunoglobulin-like transcript; LIR: leukocyte inhibitory receptor; MIR: macrophage inhibitory receptor....
, ILTs and LIR, and can exert immunomodulatory effects on a wide range of immune cells. The human genes encoding these receptors are found in a gene cluster
Gene cluster
A gene cluster is a set of two or more genes that serve to encode for the same or similar products. Because populations from a common ancestor tend to possess the same varieties of gene clusters, they are useful for tracing back recent evolutionary history...
at chromosomal region 19q13.4.
They include
- LILRA1
- LILRA2LILRA2Leukocyte immunoglobulin-like receptor subfamily A member 2 is a protein that in humans is encoded by the LILRA2 gene....
- LILRA3LILRA3Leukocyte immunoglobulin-like receptor subfamily A member 3 also known as CD85 antigen-like family member E , immunoglobulin-like transcript 6 , and leukocyte immunoglobulin-like receptor 4 is a protein that in humans is encoded by the LILRA3 gene located within the eukocyte receptor complex on...
- LILRA4LILRA4Leukocyte immunoglobulin-like receptor subfamily A member 4 is a protein that in humans is encoded by the LILRA4 gene....
- LILRA5
- LILRA6
- LILRB1LILRB1Leukocyte immunoglobulin-like receptor subfamily B member 1 is a protein that in humans is encoded by the LILRB1 gene.-Further reading:...
- LILRB2LILRB2Leukocyte immunoglobulin-like receptor subfamily B member 2 is a protein that in humans is encoded by the LILRB2 gene.-Further reading:...
- LILRB3LILRB3Leukocyte immunoglobulin-like receptor subfamily B member 3 is a protein that in humans is encoded by the LILRB3 gene....
- LILRB4LILRB4Leukocyte immunoglobulin-like receptor subfamily B member 4 is a protein that in humans is encoded by the LILRB4 gene....
- LILRB5LILRB5Leukocyte immunoglobulin-like receptor subfamily B member 5 is a protein that in humans is encoded by the LILRB5 gene....
- LILRB6 or LILRA6
- LILRB7 or LILRA5
A subset of LILR recognise MHC class I
MHC class I
MHC class I molecules are one of two primary classes of major histocompatibility complex molecules and are found on every nucleated cell of the body...
(also known as HLA
Human leukocyte antigen
The human leukocyte antigen system is the name of the major histocompatibility complex in humans. The super locus contains a large number of genes related to immune system function in humans. This group of genes resides on chromosome 6, and encodes cell-surface antigen-presenting proteins and...
class I in humans). Of these, the inhibitory receptors LILRB1
LILRB1
Leukocyte immunoglobulin-like receptor subfamily B member 1 is a protein that in humans is encoded by the LILRB1 gene.-Further reading:...
and LILRB2
LILRB2
Leukocyte immunoglobulin-like receptor subfamily B member 2 is a protein that in humans is encoded by the LILRB2 gene.-Further reading:...
show a broad specificity for classical and non-classical MHC alleles with preferential binding to b2m
Beta-2 microglobulin
β2 microglobulin also known as B2M is a component of MHC class I molecules, which are present on all nucleated cells . In humans, the β2 microglobulin protein is encoded by the B2M gene.-Structure and function:...
-associated complexes. In contrast, the activating receptors LILRA1 and LILRA3
LILRA3
Leukocyte immunoglobulin-like receptor subfamily A member 3 also known as CD85 antigen-like family member E , immunoglobulin-like transcript 6 , and leukocyte immunoglobulin-like receptor 4 is a protein that in humans is encoded by the LILRA3 gene located within the eukocyte receptor complex on...
prefer b2m-independent free heavy chains of MHC class I, and in particular HLA-C
HLA-C
HLA-C belongs to the MHC class I heavy chain receptors. The C receptor is a heterodimer consisting of a HLA-C mature gene product and β2-microglobulin. The mature C chain is anchored in the membrane...
alleles.