腫瘤壞死因子
TNF（全稱腫瘤壞死因子，Tumor Necrosis Factor）是一種能夠直接殺傷腫瘤細胞而對正常細胞無明顯毒性的細胞因子，是迄今為止所發現的直接殺傷腫瘤作用最強的生物活性因子之一。最初是在1975年，由E.A. Carswell等人發現，后于1985年經Shalaby命名，由巨噬細胞產生的TNF命名為TNF-α，而由T淋巴細胞產生的淋巴毒素（lymphotoxin，LT)命名為TNF-β。
雖然TNF-α與TNF-β僅有約30%的同源性，但它們卻擁有共同的受體。TNFα的生物學活性占TNF總活性的70 %～95 %，因此目前常說的TNF多指TNF-α。
TNFα是一種涉及到系統性炎癥的細胞因子，主要由巨噬細胞分泌。TNFα的主要功能是調節免疫細胞，作為一種內源性致熱原，可以導致發熱，引起細胞凋亡，組織腫瘤發生和病毒復制，并可以通過刺激細胞分泌IL1和IL6對敗血癥作出反應。TNFα功能失調涉及多種疾病，比如阿爾茲海默癥、銀屑病、癌癥、重度抑郁和腸炎等。TNF家族除這兩種外還發現約30種。
華美生物TNF類蛋白產品涵蓋了絕大部分TNF家族成員，這里展示了部分蛋白產品圖片：
| 產品名稱 |
貨號 |
規格 |
| Recombinant Human Tumor necrosis factor receptor superfamily member 12A protein (TNFRSF12A), partial (Active) |
CSB-AP001931HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 9 protein (TNFRSF9), partial |
CSB-AP001951HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor ligand superfamily member 9 (TNFSF9), partial (Active) |
CSB-AP001961HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor protein (TNF), partial (Active) |
CSB-AP002141HU |
500ug/100ug/10ug |
| Recombinant Human Tumor necrosis factor protein (TNF), partial (Active) |
CSB-AP002151HU |
500ug/100ug/10ug |
| Recombinant Human Tumor necrosis factor protein (TNF), partial (Active) |
CSB-AP002161HU |
500ug/100ug/10ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 13C protein (TNFRSF13C), partial (Active) |
CSB-AP002181HU |
500ug/100ug/10ug |
| Recombinant Human Tumor necrosis factor ligand superfamily member 13B (TNFSF13B), partial (Active) |
CSB-AP002191HU |
500ug/100ug/5ug |
| Recombinant Human CD40 ligand (CD40LG), partial (Active) |
CSB-AP002211HU |
500ug/100ug/10ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 17 protein (TNFRSF17), partial (Active) |
CSB-AP002271HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 10B (TNFRSF10B),Partial (Active) |
CSB-AP002291HU |
500ug/100ug/10ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 13B protein (TNFRSF13B), partial (Active) |
CSB-AP002301HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 6 protein (FAS), partial (Active) |
CSB-AP002311HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 11A protein (TNFRSF11A), partial (Active) |
CSB-AP002321HU |
500ug/100ug |
| Recombinant Human Tumor necrosis factor ligand superfamily member 15 protein (TNFSF15), partial (Active) |
CSB-AP002341HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor ligand superfamily member 18 protein (TNFSF18), partial (Active) |
CSB-AP002351HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 1A protein (TNFRSF1A), partial (Active) |
CSB-AP002361HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 1B protein (TNFRSF1B), partial (Active) |
CSB-AP002371HU |
500ug/100ug/5ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 11B protein (TNFRSF11B), partial (Active) |
CSB-AP002991HU |
500ug/100ug/10ug |
| Recombinant Human Tumor necrosis factor receptor superfamily member 11B protein (TNFRSF11B), partial (Active) |
CSB-AP003001HU |
500ug/100ug/10ug |
正如我們前面所說的，當我們提到TNF時，我們通常指的是TNFα。目前有關TNFα的作用機制已基本明了。 TNFα可以結合兩種受體，TNFR1（TNF受體1型）和TNFR2（TNF受體2型）。 TNFR1可在大多數組織中表達，可以與膜上的TNF可溶性三聚體形式結合并活化。而TNFR2通常存在于免疫系統的細胞中，可以與膜結合的TNF同源三聚體形式起作用。但就目前的研究數據而言，大多數關于TNF信號傳導均來自TNFR1，而TNFR2的作用就相對較小。TNFα與受體結合后，可激活多條信號通路，包括NFκB和MAPK信號傳導途徑。
此外，基于TNFα可以殺死腫瘤細胞這一特性， TNFα抑制劑已被用于臨床。TNFα抑制劑是一種抑制對TNFα生理反應的藥物。TNFα可參與自身免疫和免疫介導疾病，例如類風濕性關節炎、強直性脊柱炎、炎性腸病、牛皮癬、化膿性汗腺炎和難治性哮喘，它本身就是引起炎癥的一個重要因素，所有TNF抑制劑可用于這些自身免疫和免疫介導疾病的治療。目前已上市的TNFα抑制劑包括依那西普、英夫利昔單抗、阿達木單抗、賽妥珠單抗和戈利木單抗，都是通過與TNFα結合來抑制其與對應受體結合起作用。
