Account : TNF-alpha (Tumor Necrosis Factor alpha)

TNF-alpha(Tumor Necrosis Factor alpha)

Synonym:

26 kDa protein
BCDF ( B-cell differentiation factors )
BCSF ( B-cell stimulating factor )
BSF-2 ( B-cell stimulating factor-2 )
BSF-p2 ( B-cell stimulating factor p2 )
CDF ( CAT development factor , choline acetyltransferase development factor )
CDF ( Cytolytic differentiation factor for T-lymphocytes )
CDF ( Cytolytic T-lymphocyte differentiation factor )
CDF ( cytotoxic T-cell differentiation factor )
CPA ( colony promoting activity )
CSF-309 ( Hematopoietic colony stimulating factor-309 )
DIF ( differentiation inducing factor )
Differentiation inducing factor for human monoblastic leukemia cells
FDGI ( fibroblast-derived growth inhibitor )
Fibroblast derived differentiation inducing factor for human monoblastic leukemia cells
HGF ( hybridoma growth factor )
HP1
HPGF ( hybridoma/plasmacytoma growth factor )
HSF ( hepatocyte stimulating factor )
HSF-1 ( hepatocyte stimulating factor-1 )
IFN-beta-2 ( Interferon-beta-2 )
ILHP1 ( Interleukin-hemopoietin-1 )
ILHP1 ( interleukin-hybridoma/plasmacytoma-1 )
L-GI factor ( murine lung-derived growth inhibitory factor )
L-HGF ( L929-derived hybridoma growth factor)
MGI-2A ( Macrophage-granulocyte inducer-2A )
Mk potentiator
Myeloma GF ( myeloma growth factor )
Natural killer cell activity-augmenting factor
NKAF ( natural killer cell activating factor )
PCT-GF ( plasmacytoma growth factor )
TAF ( T-cell activating factor )
Thymocyte growth factor
TPO ( thrombopoietin )
TSF ( thymocyte stimulating factor )
WI-26-VA4 factor

Structure/Function

TNF-alpha is a member of a family of cytokines which also includes LIF , CNTF , Oncostatin M , ILI1 , and CT-1 . All known members of the TNF-alpha cytokine family induce hepatic expression of Acute phase proteins .

TNF-alpha is produced by many different cell types. The main sources in vivo are stimulated monocytes, fibroblasts, and endothelial cells. Macrophages, T-cells and B-lymphocytes,granulocytes, smooth muscle cells, eosinophils, chondrocytes, osteoblasts, mast cells, glial cells,and keratinocytes also produce TNF-alpha after stimulation. Glioblastoma cells constitutively produce TNF-alpha and the factor can be detected also in the cerebrospinal fluid. Human milk also contains TNF-alpha.

Physiological stimuli for the synthesis of TNF-alpha are IL-1 , bacterial endotoxins , TNF , PDGF , and Oncostatin M . In fibroblasts the synthesis of TNF-alpha is stimulated by IFN-beta , TNF-alpha , PDGF , and viral infections. In thymic stromal cells the synthesis of TNF-alpha can be induced by NGF . TNF-alpha can also stimulate or inhibits its own synthesis, depending upon the cell type.In epithelial,endothelial, and fibroblastic cells secretion of TNF-alpha is induced by IL-17 .

Protein characteristics :

TNF-alpha is a protein of 185 amino acids glycosylated at positions 73 and 172. It is synthesized as a precursor protein of 212 amino acids. Monocytes express at least five different molecular forms of TNF-alpha with molecular masses of 21.5-28 kDa. They mainly differ by post-translational alterations such as glycosylation and phosphorylation.

Gene structure :

The human TNF-alpha gene has a length of approximately 5 kb and contains five exons. It maps to human chromosome 7p21-p14 between the markers D7S135 and D7S370. The murine gene maps to chromosome 5. The nucleotide sequences of TNF-alpha and G-CSF genes resemble each other in a way suggesting a possible evolutionary relationship.

GenBank (through Genome Net)

Sequence Information

Journal Information

last updated 11/12/98