SDF-1 alpha/CXCL12 蛋白, Human

The SDF-1 alpha/CXCL12 protein is a chemoattractant for immune cells. SDF-1 alpha/CXCL12 Protein, Human is the recombinant human-derived SDF-1 alpha/CXCL12 protein, expressed by E. coli , with tag free.

SDF-1 α/CXCL12 蛋白作为化学引诱剂，对 T 淋巴细胞和单核细胞（不包括中性粒细胞）具有特定活性。CXC 趋化因子受体 CXCR4 激活后，会诱导细胞内钙离子快速瞬时升高，促进趋化作用。SDF-1-beta(3-72) 和 SDF-1-alpha(3-67) 表现出趋化活性降低，与细胞表面蛋白聚糖的结合似乎会抑制 SDF-1-alpha(3-67) 的形成，从而保留当地站点的活动。此外，它还与非典型趋化因子受体 ACKR3 结合，激活 β-arrestin 通路并充当 SDF-1 的清道夫受体。通过与整合素的变构位点（位点 2）结合，它独立于 CXCR4 激活 ITGAV:ITGB3、ITGA4:ITGB1 和 ITGA5:ITGB1。SDF-1 α/CXCL12 通过 LYN 激酶作为单核细胞迁移的正调节剂和单核细胞粘附的负调节剂，通过 CXCR4 和 ACKR3 刺激单核细胞和 T 淋巴细胞的迁移，减少单核细胞对 ICAM-1 涂层表面的粘附，β-2 整合素的配体。SDF1A/CXCR4 信号轴通过 LYN 激酶抑制 β2 整合素 LFA-1 介导的单核细胞与 ICAM-1 的粘附。它抑制CXCR4介导的T细胞系适应的HIV-1感染，在心肌梗塞后发挥保护作用，并诱导多种细胞中ACKR3的下调和内化。它在胚胎发育过程中至关重要，是 B 细胞淋巴细胞生成、骨髓中的骨髓生成和心室间隔形成所必需的。此外，SDF-1 α/CXCL12 在 IL7 存在的情况下刺激骨髓来源的 B 细胞祖细胞的增殖，以及基质细胞依赖性前 B 细胞的生长（通过相似性）。以单体或同型二聚体形式存在，平衡受到非酸性 pH、多价阴离子以及与 CXCR4 或肝素的结合的影响。单体形式对于完整的趋化活性和抵抗缺血/再灌注损伤至关重要，而二聚体形式作为 CXCR4 的部分激动剂，刺激 Ca2+ 动员而没有趋化活性，而是作为选择性拮抗剂，阻断单体形式诱导的趋化性。SDF-1 α/CXCL12 与 ACKR3 的 N 末端、整合素亚基 ITGB3（通过变构位点（位点 2））和 TNFAIP6 通过 Link 结构域相互作用。

1. Full biological activity determined by a chemotaxis bioassay using PHA and rHuIL-2 activated human peripheral blood T-lymphocytes is in a concentration range of 20-80 ng/mL.
2. Measured by its ability to chemoattract IL-2-activated human T cells. The ED₅₀ for this effect is approximately ≤45.17 ng/mL, corresponding to a specific activity is ≥2.214×10⁴ U/mg.

Human

E. coli

Tag Free

P48061-2 (K22-K89)

6387  [NCBI]

KPVSLSYRCPCRFFESHVARANVKHLKILNTPNCALQIVARLKNNNRQVCIDPKLKWIQEYLEKALNK

Approximately 8-10.0 kDa

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

无菌粉末

Lyophilized from a 0.2 μm filtered solution of 20 mM PB, 150 mM NaCl, pH 7.4 or 20 mM PB, 130 mM NaCl, pH 7.3.

<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. 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.