TGF-β (transforming growth factor TGF-β) is a pleiotropic and pleiotropic cytokine that regulates cell proliferation and differentiation by opening the receptor signal cascade transduction pathway on the cell surface , Migration and apoptosis have important regulatory effects on the synthesis of extracellular matrix, the repair of wounds, and the function of the immune system.
Illustrates: TGF-β inhibition of swelling in the tumor adapted play in immunity important role ( stimulation; inhibition)
There are two signal transduction pathways of TGF-β: TGF-β-Smad signal pathway and Non-Smad signal pathway. The Smad signaling pathway is the main pathway for TGF-β to produce biological effects. TGF-β forms a dimer receptor complex with type II receptor (TGF-βR II) and type I receptor (TGF-βR I, also known as ALK5) on the cell surface, and the cell membrane surface type III receptor ( TGF-βRIII) also participates in this process and plays a certain auxiliary role. Type II receptor phosphorylates and activates type I receptor, then type I receptor phosphorylates its connected Smad protein molecule (Smad2/3) and releases it into the cytoplasm, forms a complex with Smad4 protein and transfers to the nucleus to bind Different transcription factors and transcription co-activators or transcription co-inhibitors regulate the transcription of TGF-β target genes and produce biological effects. Other signal pathways of TGF-β include mitogen-activated protein kinase pathway, extracellular signal-regulated kinase (ERK) pathway, JNK, P38, PI3K kinase, PP2A phosphatase and Rho family members.
Studies have shown that in the tumor microenvironment a certain concentration of the TGF-β cytokines promote tumor growth and metastasis. Therefore, selective inhibition of the up-regulated TGF-β around tumor cells has gradually become a popular treatment strategy for the treatment of non-small cell lung cancer, bladder cancer and other diseases.
We use the luciferase reporter gene detection system as the platform and use the adherent and stably transfected 293T-TGF-β-Luc functional detection cell line, which can provide TGF-β antibody blocking or neutralization activity detection services, for TGF Preclinical studies of -β targets provide solutions.
293T-TGF-β-Luc activation experiment principle
Illustration: Use lentivirus to integrate TGF-β receptor gene, SMAD gene, PAI-1 promoter and Luciferase gene into 293T cells. When the TGF-β protein binds to the TGF-β receptor on the 293T cell membrane, the intracellular signal of the TGF-β receptor is activated, which further causes the SMAD protein in the cytoplasm to form a phosphorylated complex, and then the complex is in the nucleus. It is combined with the PAI-1 promoter to start the expression of Luciferase gene, which eventually leads to an increase in the expression level of Luciferase. Figure1, Figure 2 and Figure 3 are the results of the detection of Luciferase expression level after 18h treatment with different concentrations of TGF-β1, TGF-β2, and TGF-β3 proteins.
293T-TGF-β-Luc function blocking experiment principle
The diagram illustrates: After TGF-β protein binds to the TGF-β receptor on the 293T cell membrane, it causes the activation of the TGF-β receptor intracellular signal, which further causes the SMAD protein in the cytoplasm to form a phosphorylated complex, and then the complex The substance transfers to the nucleus, binds to the PAI-1 promoter, starts the expression of Luciferase gene, and increases the expression level of Luciferase. In this detection system, after adding anti-TGF-β or anti-TGF-βR (TGF-β receptor) antibodies with blocking function, the TGF-β protein cannot bind to the TGF-β receptor, and the activation signal The pathway is blocked and the expression level of Luciferase is reduced. Figure 1 shows the detection results of Luciferase expression level after 18h treatment with different concentrations of anti-TGF-β1.