γ-干擾素

干擾素-γ（Interferon gamma、Interferon-γ、IFNG、IFNγ）是水溶性二聚體的細胞因子^[2]。是II型干擾素的唯一成員^[3]曾被稱為巨噬細胞活化因子。

干擾素-γ
γ-干擾素晶體結構線狀表示[1]
有效結構 PDB 直系同源檢索：PDBe, RCSB PDB查詢代碼列表 1EKU, 1FG9, 1FYH, 1HIG, 3BES
標識
代號	IFNG; IFG; IFI
擴展標識	遺傳學：147570 鼠基因：107656 同源基因：55526 GeneCards: IFNG Gene
基因本體論描述 分子功能 · cytokine activity · interferon-gamma receptor binding 細胞成分 · extracellular region · extracellular space · external side of plasma membrane 生物過程 · protein import into nucleus, translocation · negative regulation of transcription from RNA polymerase II promoter · neutrophil apoptotic process · regulation of the force of heart contraction · positive regulation of mesenchymal cell proliferation · adaptive immune response · CD8-positive, alpha-beta T cell differentiation involved in immune response · negative regulation of mesenchymal to epithelial transition involved in metanephros morphogenesis · apoptotic process · cellular component movement · humoral immune response · cell cycle arrest · cell surface receptor signaling pathway · response to virus · cytokine-mediated signaling pathway · antigen processing and presentation · neutrophil chemotaxis · endoplasmic reticulum unfolded protein response · negative regulation of myelination · positive regulation of synaptic transmission, cholinergic · negative regulation of interleukin-17 production · positive regulation of interleukin-12 production · positive regulation of interleukin-23 production · positive regulation of tumor necrosis factor production · positive regulation of peptidyl-serine phosphorylation of STAT protein · positive regulation of smooth muscle cell apoptotic process · positive regulation of T cell proliferation · response to drug · positive regulation of tyrosine phosphorylation of Stat1 protein · defense response to bacterium · defense response to protozoan · negative regulation of growth of symbiont in host · positive regulation of chemokine biosynthetic process · positive regulation of interleukin-12 biosynthetic process · positive regulation of MHC class II biosynthetic process · positive regulation of interleukin-6 biosynthetic process · positive regulation of nitric oxide biosynthetic process · positive regulation of neuron differentiation · positive regulation of osteoclast differentiation · positive regulation of cell adhesion · positive regulation of transcription from RNA polymerase II promoter · positive regulation of isotype switching to IgG isotypes · negative regulation of smooth muscle cell proliferation · positive regulation of interleukin-1 beta secretion · regulation of insulin secretion · positive regulation of membrane protein ectodomain proteolysis · defense response to virus · positive regulation of killing of cells of other organism · interferon-gamma-mediated signaling pathway · regulation of interferon-gamma-mediated signaling pathway · positive regulation of fructose 1,6-bisphosphate 1-phosphatase activity · positive regulation of fructose 1,6-bisphosphate metabolic process · positive regulation of vitamin D biosynthetic process · positive regulation of calcidiol 1-monooxygenase activity · cellular response to lipopolysaccharide · cellular response to interleukin-18 · negative regulation of metanephric nephron tubule epithelial cell differentiation · positive regulation of tumor necrosis factor (ligand) superfamily member 11 production Sources: Amigo / QuickGO
RNA表達模式
更多表達數據
直系同源體
物種	人類	小鼠
Entrez	3458	15978
Ensembl	ENSG00000111537	ENSMUSG00000055170
UniProt	P01579	P01580
mRNA序列	NM_000619	NM_008337
蛋白序列	NP_000610	NP_032363
基因位置	Chr 12: 68.55 – 68.55 Mb	Chr 10: 118.44 – 118.45 Mb
PubMed查詢	[1]	[2]
閱 論 編

IFN-γ
Crystal structure of a biologically active single chain mutant of human interferon gamma
鑑定
標誌	?
Pfam	PF00714（舊版）
Pfam宗系	CL0053（舊版）
InterPro（英語：InterPro）	IPR002069
SCOP（英語：Structural Classification of Proteins）	1rfb / SUPFAM
現有可用的蛋白結構： Pfam 結構（舊版） / ECOD PDB RCSB PDB; PDBe; PDBj PDBsum（英語：PDBsum） 結構概要

Γ-干擾素

臨床資料
商品名（英語：Drug nomenclature）	Actimmune
AHFS/Drugs.com	Monograph
MedlinePlus	a601152
ATC碼	L03AB03 (WHO)
識別資訊
IUPAC命名法 Human interferon gamma-1b
CAS號	82115-62-6  Y 98059-61-1
DrugBank	DB00033 N
ChemSpider	NA Y
ChEMBL	ChEMBL1201564 N
化學資訊
化學式	C761H1206N214O225S6
摩爾質量	17145.6 g/mol

結構

干擾素-γ的單體是由六個α螺旋組成一個核心^[4]和在C端區延伸展開的片斷序列。

生物活性的二聚體是由兩個反平行相互鎖定的單體形成。

生物活性

所有的細胞都可以產生干擾素-α（英語：Interferon alfa）和干擾素-β， 而干擾素-γ只由自然殺傷細胞（NK細胞）和活化的T細胞產生。I型干擾素對酸穩定，而干擾素-γ則遇酸變性。

干擾素-γ具有抗病毒、免疫調節及抗腫瘤特性^[5]。干擾素-γ可以與干擾素伽瑪受體（英語：Interferon-gamma receptor）(IFNGR)結合，進而調節JAK-STAT通路。干擾素-γ激活抗原提呈細胞，通過上調轉錄因子T-bet而促進I型輔助T細胞(Th1細胞)的分化。

干擾素-γ是I型輔助T細胞(Th1細胞)的標誌性的細胞因子。II型輔助T細胞(Th2細胞)釋放白細胞介素-4（IL-4）和白細胞介素-13（IL-13）。自然殺傷細胞和CD8⁺T細胞也產生干擾素-γ。干擾素-γ通過迅速降解RANK-RANKL信號通路的TRAF6而抑制破骨細胞形成。

治療用途

干擾素可以用來治療傳染病，但也能促成自體免疫。在接受干擾素伽瑪治療的病人中，多達19%的病人會有自體免疫.

干擾素IFNγ用於豬生殖與呼吸道綜合症PRRSV的治療上，有試驗發現干擾素IFNγ能活化先天免疫細胞，進而達到抑制病毒數量的效果。^[6]

A型流感的治療上，也有小鼠試驗表現出當缺失干擾素後，流感感染小鼠死亡率大幅提升且體內病毒數量維持高濃度水平；相較之下，體內有干擾素存在的小鼠，流感病毒數量隨著干擾素的生成而逐漸下降。^[7]

參考文獻

1. PDB 1FG9; Thiel DJ, le Du MH, Walter RL, D'Arcy A, Chène C, Fountoulakis M, Garotta G, Winkler FK, Ealick SE. Observation of an unexpected third receptor molecule in the crystal structure of human interferon-gamma receptor complex. Structure. September 2000, 8 (9): 927–36. PMID 10986460. doi:10.1016/S0969-2126(00)00184-2.
2. Gray PW, Goeddel DV. Structure of the human immune interferon gene. Nature. 1982 Aug 26;298(5877):859-63.
3. Gray PW, Goeddel DV. Structure of the human immune interferon gene. Nature. August 1982, 298 (5877): 859–63. PMID 6180322. doi:10.1038/298859a0.
4. Ealick SE, et al., Three-dimensional structure of recombinant human interferon-gamma. Science. 1991 May 3;252(5006):698-702.
5. Schroder K, Hertzog PJ, Ravasi T, Hume DA. Interferon-gamma: an overview of signals, mechanisms and functions. J Leukoc Biol. 2004 Feb;75(2):163-89.
6. Bautista, E. M.; Molitor, T. W. IFNγ inhibits porcine reproductive and respiratory syndrome virus replication in macrophages. Archives of Virology. 1999-06, 144 (6): 1191–1200. ISSN 0304-8608. doi:10.1007/s007050050578.
7. Hoshino, Akinori; Takenaka, Hiroshi; Mizukoshi, Osamu; Imanishi, Jiro; Kishida, Tsunataro; Tovey, Michael G. Effect of anti-interferon serum of influenza virus infection in mice. Antiviral Research. 1983-03, 3 (1): 59–65. ISSN 0166-3542. doi:10.1016/0166-3542(83)90015-3.

延伸閱讀

• Hall, Stephen K. A commotion in the blood: life, death, and the immune system. New York: Henry Holt. 1997. ISBN 0-8050-5841-9.
• Ikeda H, Old LJ, Schreiber RD. The roles of IFN gamma in protection against tumor development and cancer immunoediting.. Cytokine Growth Factor Rev. 2002, 13 (2): 95–109. PMID 11900986. doi:10.1016/S1359-6101(01)00038-7.
• Chesler DA, Reiss CS. The role of IFN-gamma in immune responses to viral infections of the central nervous system.. Cytokine Growth Factor Rev. 2003, 13 (6): 441–54. PMID 12401479. doi:10.1016/S1359-6101(02)00044-8.
• Dessein A, Kouriba B, Eboumbou C, Dessein H, Argiro L, Marquet S, Elwali NE, Rodrigues V, Li Y, Doumbo O, Chevillard C. Interleukin-13 in the skin and interferon-gamma in the liver are key players in immune protection in human schistosomiasis.. Immunol. Rev. 2005, 201: 180–90. PMID 15361241. doi:10.1111/j.0105-2896.2004.00195.x.
• Joseph AM, Kumar M, Mitra D. Nef: "necessary and enforcing factor" in HIV infection.. Curr. HIV Res. 2005, 3 (1): 87–94. PMID 15638726. doi:10.2174/1570162052773013.
• Copeland KF. Modulation of HIV-1 transcription by cytokines and chemokines.. Mini reviews in medicinal chemistry. 2006, 5 (12): 1093–101. PMID 16375755. doi:10.2174/138955705774933383.
• Chiba H, Kojima T, Osanai M, Sawada N. The significance of interferon-gamma-triggered internalization of tight-junction proteins in inflammatory bowel disease.. Sci. STKE. 2006, 2006 (316): pe1. PMID 16391178. doi:10.1126/stke.3162006pe1.
• Tellides G, Pober JS. Interferon-gamma axis in graft arteriosclerosis.. Circ. Res. 2007, 100 (5): 622–32. PMID 17363708. doi:10.1161/01.RES.0000258861.72279.29.

參看

• T細胞
• 輔助T細胞
• II型干擾素
• 細胞因子

外部連結

• MeSH|Interferon+Type+II （頁面存檔備份，存於網際網路檔案館）