S100A9 蛋白, Human

S100A9 Protein is an acidic protein. S100A9 Protein activates pro-inflammatory signaling pathways by binding to TLR4/MD2 and RAGE receptors, regulating transcription factors such as NF-κB, CREB-1, STAT3/STAT5, etc. S100A9 Protein forms a heterodimer (calprotectin) with S100A8. S100A9 Protein enhances cytokine secretion under inflammatory stimulation, promotes immune cell migration, regulates vascular endothelial permeability, induces tumor cell apoptosis, and exerts antibacterial effects through metal ion chelation.

S100A9 Protein 属于 S100 钙结合蛋白家族，该家族成员含有 EF-hand 结构域，具有钙依赖性调控功能^[3][7]。S100A9 Protein 是由单核细胞、中性粒细胞等髓系细胞表达的酸性蛋白，常与 S100A8 形成异二聚体 (钙卫蛋白)，参与炎症、免疫及宿主防御过程^[1][2][5]。S100A9 Protein 通过结合 TLR4/MD2 和 RAGE 受体激活促炎信号通路，调控 NF-κB、CREB-1、STAT3/STAT5 等转录因子，影响细胞因子 (如 IL-8) 分泌；通过与微管蛋白相互作用调节细胞骨架重组，促进吞噬细胞跨内皮迁移；还可通过螯合锌离子发挥抗菌活性或诱导肿瘤细胞凋亡^{[1][4][5][6][7]}。S100A9 Protein 主要在中性粒细胞、单核细胞的胞质中表达，在炎症状态下可分泌至细胞外，富集于炎症部位的内皮细胞表面及体液中^[1][5][7]。S100A9 Protein, Human 与小鼠等其他种属的同源蛋白在氨基酸序列和功能上高度保守，均通过钙/锌离子依赖的构象变化介导生物学效应，但部分调控位点 (如小鼠 S100A9 缺乏 Thr113 磷酸化位点) 存在差异^[4][7]。S100A9 Protein, Human 由 119 个氨基酸组成，分子量约 14 kDa，含有两个 EF-hand 钙结合结构域，可形成同源二聚体或与 S100A8 形成异二聚体，其活性依赖于钙/锌离子的协同结合及 p38 MAPK 等激酶的磷酸化修饰^[1][4][7]。S100A9 Protein, Human 增强炎症刺激下的细胞因子分泌，促进免疫细胞迁移，调控血管内皮通透性，诱导肿瘤细胞凋亡，以及通过金属离子螯合发挥抗菌作用^[1][5][6][7]。

S100A9 Protein, Human (10 μg/mL；30 min) 可通过激活 NF-κB 和 CREB-1 等转录因子，增强 fMLP 或 GM-CSF 刺激的 IL-8 产生^[1]。
S100A9 Protein, Human (1.25-10 μM；1-4 d) 诱导 MM46 小鼠乳腺癌细胞凋亡^[6]。

Measured by its ability to induce CXCL1/KC secretion by C3H10T1/2 mouse embryonic fibroblast cells. The ED₅₀ for this effect is 1.616 - 3.731 μg/mL.

• 
  Measured by its ability to enhance CXCL1secretion by C3H/10T1/2 Mouse embryonic fibroblasts. The ED₅₀ for this effect is 3.295 μg/mL, corresponding to a specific activity is 303.4901 U/mg.

Human

E. coli

Tag Free

P06702 (T2-P114)

6280  [NCBI]

Partial

TCKMSQLERNIETIINTFHQYSVKLGHPDTLNQGEFKELVRKDLQNFLKKENKNEKVIEHIMEDLDTNADKQLSFEEFIMLMARLTWASHEKMHEGDEGPGHHHKPGLGEGTP

Approximately 14.0 kDa

• 
  Greater than 95% as determined by reducing SDS-PAGE.

无菌粉末.

Lyophilized from a 0.2 μm filtered solution of PBS, pH 7.4 or 50 mM Tris-HCL, 300 mM NaCL, pH 8.0 or PBS, pH 7.4, 8% trehalose.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O. For long term storage it is recommended to add a carrier protein (0.1% BSA, 5% HSA, 10% FBS or 5% Trehalose).

Stored at -20°C for 2 years from date of receipt. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.

• [1]. Simard JC, et al. Human S100A9 potentiates IL-8 production in response to GM-CSF or fMLP via activation of a different set of transcription factors in neutrophils. FEBS Lett. 2014 Jun 13;588(13):2141-6.  [Content Brief]

  [2]. Miyasaki KT, et al. In vitro antimicrobial activity of the human neutrophil cytosolic S-100 protein complex, calprotectin, against Capnocytophaga sputigena. J Dent Res. 1993 Feb;72(2):517-23.  [Content Brief]

  [3]. Fanò G, et al. The S-100: a protein family in search of a function. Prog Neurobiol. 1995 May;46(1):71-82.  [Content Brief]

  [4]. Vogl T, et al. MRP8 and MRP14 control microtubule reorganization during transendothelial migration of phagocytes. Blood. 2004 Dec 15;104(13):4260-8.  [Content Brief]

  [5]. Viemann D, et al. Myeloid-related proteins 8 and 14 induce a specific inflammatory response in human microvascular endothelial cells. Blood. 2005 Apr 1;105(7):2955-62.  [Content Brief]

  [6]. Nakatani Y, et al. Regulation of S100A8/A9 (calprotectin) binding to tumor cells by zinc ion and its implication for apoptosis-inducing activity. Mediators Inflamm. 2005 Oct 24;2005(5):280-92.  [Content Brief]

  [7]. Björk P, et al. Identification of human S100A9 as a novel target for treatment of autoimmune disease via binding to quinoline-3-carboxamides. PLoS Biol. 2009 Apr 28;7(4):e97.  [Content Brief]