Untitled - D Ank Unlimited

CD8 molecule 142 CD15
D1
D2
D3
D4
CD4 CD8
α β
Outline structure of CD4 and CD8 coreceptor molecules.
Space-filling model of human CD8 T cell receptor.
CD8 molecule
A heterodimer of an α and β chain that are covalently associated
by disulfide bond. The two chains of a dimer have
similar structures, each having a single domain resembling
an immunoglobulin variable domain and a stretch of peptide
believed to be in a relatively extended confirmation.
CD8 T cells
The T cell subset that expresses CD8 coreceptor and recognizes
peptide antigens presented by major histocompatibility
complex (MHC) class I molecules.
CD9
A single chain protein (molecular weight of 24 kDa) that
is present on pre-B cells, monocytes, granulocytes, and
platelets. Antibodies against the molecule can cause platelet
aggregation. The CD9 antigen has protein kinase activity. It
may be significant in aggregation and activation of platelets.
CD10
An antigen, also referred to as common acute lymphoblastic
leukemia antigen (CALLA), that has a molecular weight of
100 kDa. CD10 is now known to be a neutral endopeptidase
(enkephalinase). It is present on many cell types, including
stem cells, lymphoid progenitors of B and T cells, renal
epithelium, fibroblasts, and bile canaliculi.
CD11
A family of three leukocyte-associated, single chain molecules
identified in recent years (sometimes referred to as the leukocyte
function-associated antigen [LFA]/Mac-1 family). They all
consist of two polypeptide chains; the larger of these chains (α)
is different for each member of the family; the smaller chain (β)
is common to all three molecules (see CD11a, CD11b, CD11c).
CD11a
The α chain of the leukocyte function associated-1 antigen
(LFA-1) molecule. It has a molecular weight of 180 kDa and
is present on leukocytes, monocytes, macrophages, and granulocytes
but not on platelets. LFA-1 binds the intercellular
adhesion molecules ICAM-1 (CD54), ICAM-2, and ICAM-3.
CD11b
The α chain of Mac-1 (C3bi receptor). It has a molecular
weight of 170 kDa and is present on granulocytes, monocytes,
and natural killer (NK) cells.
CD11c
The α chain of the p150,95 molecule. It has a molecular
weight of 150 kDa and is present on granulocytes, monocytes,
and natural killer (NK) cells. It reacts very strongly
with hairy cell leukemia. The antigen is weakly expressed
on B and T cell subsets.
CD12
Little is known about this antigen, which has a molecular
weight of 90 to 120 kDa. It is present on some monocytes,
granulocytes, and platelets.
CD13
An antigen (molecular weight of 130 kDa) that is a single
chain membrane glycoprotein. It is present on monocytes,
granulocytes, some macrophages, and connective tissue.
CD13 has recently been shown to be aminopeptidase-N. It
functions as a zinc metalloproteinase.
CD14
An antigen (molecular weight of 55 kDa) that is a single
chain membrane glycoprotein. It is found principally on
monocytes but also on granulocytes, dendritic reticulum
cells, and some tissue macrophages. It serves as a receptor
for lipopolysaccharide (LPS) and for lipopolysaccharidebinding
protein (LBP).
CD15
A carbohydrate antigen that is often referred to as hapten X and
consists of galactose, fucose, and N-acetyl-glucosamine linked
in a specific sequence. The antigen appears to be particularly
immunogenic in mice and numerous monoclonal antibodies of
this oligosaccharide specificity have been produced. CD15 is
present in neutrophil secondary granules of granulocytic cells
that express the antigen strongly late in their maturation. It is
also present on eosinophils, monocytes, and Reed–Sternberg
and Hodgkin cells but can also be found on non-Hodgkin cells.
CD15 is also termed Lewis-x (Le x ).
Leu M1 in Hodgkin disease.