AITRL/TNFSF18 Trimer 蛋白, Human (Biotinylated, HEK293, His-Flag)

AITRL, a type II transmembrane protein, is a ligand for glucocorticoid-induced TNFR-related protein (GITR). When AITRL binds to GITR, GITR can produce costimulatory signals that regulate T-cell proliferation and effector functions. GITR/AITRL interaction plays a role in the pathogenesis of tumor, inflammation, as well as autoimmune diseases^[1]. Besides, AITRL plays a role in endothelial cells (EC)-activation and increases STAT-1 phosphorylation and the expression of adhesion molecules (VCAM-1, ICAM-1)^[2]. AITRL/TNFSF18 Protein, Human (Biotinylated, HEK293, His-Flag) is a recombinant biotinylated human AITRL (Q72-S199) with N-terminal His and Flag tag, which is expressed in HEK293.

GITRL (AITRL) 是一种 II 型跨膜蛋白，是糖皮质激素诱导的 TNFR 相关蛋白 (GITR) 的配体。GITR 是 TNFR 超家族的成员，在 T 细胞、自然杀伤细胞和一些骨髓细胞中表达。而GITRL主要表达于抗原呈递细胞（B细胞、树突状细胞）、巨噬细胞和内皮细胞（EC）^[1]。
当GITRL与GITR结合时，GITR可产生共刺激信号调节 T 细胞增殖和效应功能。这种相互作用刺激 CD4⁺ Teff 和 Treg 细胞的增殖和细胞因子产生，并驱动 CD8⁺ T 细胞^[3]的抗肿瘤活性。此外，GITRL 在 EC 激活中发挥作用，并促进小鼠和人类的粘附，从而增加 STAT-1 磷酸化并增强 VCAM-1 和 ICAM-1 等粘附分子的表达^[2]。
人类 GITRL 与小鼠的共同氨基酸一致性< 55%。人 GITRL 由胞质结构域 (M1-W27)、螺旋结构域 (L28-F48) 和胞外结构域 (L49-S177) 组成。人GITRL是一个三聚体，但也可以是单体或组装成其他多聚体结构^[4]。
GITR/GITRL相互作用在肿瘤、炎症等的发病机制中发挥着重要作用作为自身免疫性疾病^[1]。

AITRL (human, 48 h) reduces the suppressive capacity of MDSCs on CD4⁺ T cells (MDSCs induced from healthy donors)^[5].

1.Immobilized Human GITR His at 1 μg/mL (100 μL/Well). Dose response curve for Biotinylated Human GITR Ligand Trimer His with the EC₅₀ of 0.2 μg/mL determined by ELISA.
2.Immobilized Human GITR His at 5 μg/mL (100 μL/Well). Dose response curve for Biotinylated Human GITR Ligand Trimer His with the EC₅₀ of 1.69 μg/mL determined by ELISA.

Human

HEK293

N-His;N-Flag

Q9UNG2 (Q50-S177)

8995  [NCBI]

QLETAKEPCMAKFGPLPSKWQMASSEPPCVNKVSDWKLEILQNGLYLIYGQVAPNANYNDVAPFEVRLYKNKDMIQTLTNKSKIQNVGGTYELHVGDTIDLIFNSEHQVLKNNTYWGIILLANPQFIS

50-70 kDa

Greater than 95% as determined by Tris-Bis PAGE.

无菌粉末.

Lyophilized a 0.22 μm filtered solution of PBS, pH 7.4. Normally 8% trehalose is added as protectant before lyophilization.

<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.

• [1]. Tian J, et al. The Role of GITR/GITRL Interaction in Autoimmune Diseases. Front Immunol. 2020 Oct 9;11:588682.  [Content Brief]

  [2]. Lacal PM, et al. Glucocorticoid-induced tumor necrosis factor receptor family-related ligand triggering upregulates vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 and promotes leukocyte adhesion. J Pharmacol Exp Ther. 2013 Oct;347(1):164-72.  [Content Brief]

  [3]. Wang F, et al. Structures of mouse and human GITR-GITRL complexes reveal unique TNF superfamily interactions. Nat Commun. 2021 Mar 2;12(1):1378.  [Content Brief]

  [4]. Placke T, et al. Glucocorticoid-induced TNFR-related (GITR) protein and its ligand in antitumor immunity: functional role and therapeutic modulation. Clin Dev Immunol. 2010;2010:239083.  [Content Brief]

  [5]. Tian J, et al. Increased GITRL Impairs the Function of Myeloid-Derived Suppressor Cells and Exacerbates Primary Sjögren Syndrome. J Immunol. 2019 Mar 15;202(6):1693-1703.  [Content Brief]