Immunoglobulin family
A group of functionally and structurally related proteins that play a key role in the immune system is called the large immunoglobulin family (immunoglobulin superfamily). The immunoglobulins include antibodies, specific receptors for T-lymphocyte and B-lymphocytes, HLA molecules, adhesion molecules, and growth factor receptors. They are expressed mainly on leukocytes, but some are also found on other cells (e.g. HLA class I on all nuclear cells). They occur as free molecules or are incorporated into the cell membrane.
Immunoglobulin domain[edit | edit source]
A characteristic feature of immunoglobulins is the presence of the so-called immunoglobulin domain in their structure. The domains contain about 100 amino acids. They have a globular structure. The peculiarity is that they form incomplete rings connected by a sulphide bridge of two cysteines (see figure). Immunoglobulin domains are classified according to their variability within a single type of molecule.
Variable[edit | edit source]
Domains with high variability (hypervariable). They are usually found in the part of the molecule that contacts the antigens or ligands. They are referred to as V 1-n.
For more information see Genetics of Ig, B and T receptors.Constant[edit | edit source]
This type of immunoglobulin domain is characteristic of single molecules. They further determine the reaction upon ligand binding. They are referred to as C 1-n.
Transient[edit | edit source]
Domains that retain a partially constant form but may vary are called transient. They are denoted H1-n.
Function of immunoglobulins[edit | edit source]
All immunoglobulin molecules are able to recognize their specific ligands (with varying degrees of accuracy). They are therefore essential agents in specific immunity.
Links[edit | edit source]
Related articles[edit | edit source]
Used literature[edit | edit source]
- ŠTERZL, Ivan, et al. Základy imunologie pro zubní a všeobecné lékaře. 1. edition. Praha : Karolinum, 2005. 207 pp. ISBN 978-80-246-0972-0.
A group of functionally and structurally related proteins that play a key role in the immune system is called the large immunoglobulin family (immunoglobulin superfamily). The immunoglobulins include antibodies
, specific receptors for
T-lymphocyte
and
B-lymphocytes
,
HLA molecules
, adhesion molecules, and growth factor receptors. They are expressed mainly on leukocytes, but some are also found on other cells (e.g. HLA class I on all nuclear cells). They occur as free molecules or are incorporated into the cell membrane.
Immunoglobulin domain
Immunoglobulin basic unit
A characteristic feature of immunoglobulins is the presence of the so-called immunoglobulin domain in their structure. The domains contain about 100 amino acids. They have a globular structure. The peculiarity is that they form incomplete rings connected by a sulphide bridge of two cysteines (see figure). Immunoglobulin domains are classified according to their variability within a single type of molecule.
Variable
Domains with high variability (hypervariable). They are usually found in the part of the molecule that contacts the antigens
or
ligands
. They are referred to as V 1-n.
Constant
This type of immunoglobulin domain is characteristic of single molecules. They further determine the reaction upon ligand binding. They are referred to as C 1-n.
Transient
Domains that retain a partially constant form but may vary are called transient. They are denoted H1-n.
Function of immunoglobulins
All immunoglobulin molecules are able to recognize their specific ligands (with varying degrees of accuracy). They are therefore essential agents in specific immunity
.
Links
Related articles
Used literature
- ŠTERZL, Ivan, et al. Základy imunologie pro zubní a všeobecné lékaře. 1. edition. Praha : Karolinum, 2005. 207 pp. ISBN 978-80-246-0972-0.
