BAFF receptor (B-cell activating factor receptor, BAFF-R), also known as tumor necrosis factor receptor superfamily member 13C (TNFRSF13C) and BLyS receptor 3 (BR3), is a

membrane protein Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins are a permanent part of a cell membrane ...

of the

TNF receptor The tumor necrosis factor receptor superfamily (TNFRSF) is a protein superfamily of cytokine receptors characterized by the ability to bind tumor necrosis factors (TNFs) via an extracellular cysteine-rich domain. With the exception of nerve growth ...

superfamily which recognizes BAFF, an essential factor for B cell maturation and survival. In humans it is encoded by the ''TNFRSF13C''

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

Function

B-cell activating factor B-cell activating factor (BAFF) also known as tumor necrosis factor ligand superfamily member 13B and CD257 among other names, is a protein that in humans is encoded by the ''TNFSF13B'' gene. BAFF is also known as B Lymphocyte Stimulator (BLyS) a ...

(BAFF) enhances B-cell survival in vitro and is a regulator of the peripheral

B-cell B cells, also known as B lymphocytes, are a type of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted or inserted into the plasm ...

population. The protein encoded by this gene is a receptor for BAFF and is a type III

transmembrane protein A transmembrane protein is a type of integral membrane protein that spans the entirety of the cell membrane. Many transmembrane proteins function as gateways to permit the transport of specific substances across the membrane. They frequently un ...

containing a single extracellular

phenylalanine Phenylalanine (symbol Phe or F) is an essential α-amino acid with the chemical formula, formula . It can be viewed as a benzyl group substituent, substituted for the methyl group of alanine, or a phenyl group in place of a terminal hydrogen of ...

-rich domain. It is thought that this receptor is the principal receptor required for BAFF-mediated mature B-cell survival. In B cell maturation, due to regulation by BAFF-R, only a limited amount of B-cell will survive.

Clinical significance

Overexpression of BAFF in mice results in mature B-cell

hyperplasia Hyperplasia (from ancient Greek ὑπέρ ''huper'' 'over' + πλάσις ''plasis'' 'formation'), or hypergenesis, is an enlargement of an organ or tissue caused by an increase in the amount of Tissue (biology), organic tissue that results from ...

and symptoms of

systemic lupus erythematosus Lupus, formally called systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Common ...

(SLE). Also, some SLE patients have increased levels of BAFF in serum. Therefore, it has been proposed that abnormally high levels of BAFF may contribute to the pathogenesis of autoimmune diseases by enhancing the survival of autoreactive B cells, which are cells that show immune response to normal body cells. Autoreactive B cells are less sensitive toward BAFF and are usually outcompeted by the normal B cells in the maturation process regulated by low BAFF-R expression. An elevated level of BAFF-R can therefore overcome this decreased response and result in accumulation of autoreactive B cells. BAFF and BAFF-R pair can also down-regulate the cell

apoptosis Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...

process.

Function

Clinical significance

See also

References

External links

Further reading