结构专家又添新作：经抗体验证的RSV Pre & Post F蛋白

不久前，Science公布了2022年度十大科学突破，RSV疫苗的突破进展成功入选。呼吸道合胞病毒（Respiratory Syncytial Virus, RSV）作为引起急性下呼吸道感染（ALRTIs）的主要原因之一，每年导致全球约3.31亿人发生呼吸道感染。然而，就是这样一个常见且早已被发现的呼吸道病毒，其疫苗的研发却十分坎坷，以至于至今仍无一款成熟的RSV疫苗问世。

此前的数十年间，科学家们不曾停止对于RSV疫苗的研究与开发，但均以失败告终。究其原因，可能是因为RSV病毒结构的特殊性。病毒表面的融合蛋白（fusion protein , F）和粘附蛋白（attachment protein, G）因在病毒入侵过程中的关键作用成为病毒研究的理想靶点，而其中G蛋白变异较多相对不稳定，F蛋白也存在Pre到Post构象转变影响其稳定性。

RSV F蛋白融合前及融合后构象

为了克服这一障碍，科学家们对RSV F蛋白的蛋白结构及其抗体进行了研究，发现该蛋白表面至少存在7个完全不同的抗原表位，并成功筛选到可以与不同表位结合的抗体，分别为φ site_D25/5C4/AM22，I site_131-2A/2F，II site_motavizumab/palivizumab，III site_MPE8，IV site_101F/mAb19，V site_hRSV90。其中识别IV表位的101F、识别II表位的palivizumab和识别I表位的131-2A抗体可以同时识别F蛋白的pre和post构象，识别φ表位的D25抗体只与Pre构象的F蛋白发生结合，识别III表位的MPE8抗体则偏好识别Pre构象，与Post构象具有较弱的结合活性[1]。2010年，Kwakkenbos研究团队筛选获得单克隆抗体AM14，其识别的抗原表位位于F-pre蛋白近赤道区域，横跨两个单体，可特异性识别F-pre三聚体结构，且被证明与此前中和效果最佳的D25抗体具有相似的中和活性和更快的动力学性质^[2,3]。

RSV-F蛋白抗原表位及抗体结合情况^[2,3]

基于成熟的蛋白表达平台与结构验证方案，在对RSV病毒进行充分调研后，我们开发了RSV病毒研究关键的G蛋白与不同构象的F蛋白，并从上述抗体中选择了代表性抗体对所表达的Pre及Post构象F蛋白进行验证，力求为广大客户提供真正的Pre & Post RSV-F蛋白！

★ 纯度经SDS-PAGE验证>95%，经SEC-MALS验证>90%。

The purity of HRSV (A) Fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H7) is greater than 95% verified by SDS-PAGE and more than 90% verified by SEC-MALS.

★ RSV Pre-F蛋白(Cat. No. RSF-V52H7)与Post-F蛋白(Cat. No. RSF-V52H6)和抗体101F、5C4、AM14、131-2A、D25结合活性经ELISA验证，与文献结果一致。

Immobilized HRSV (A) Post-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H6) and HRSV (A) Pre-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H7) at 1 μg/mL (100 μL/well) can bind Anti-Fusion glycoprotein F0 Antibody, Mouse IgG2a (101F) with a linear range of 0.1-4 ng/mL (QC tested).

Immobilized HRSV (A) Pre-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H7) at 1 μg/mL (100 μL/well) can bind Recombinant Mouse Anti-RSV F Antibody (5C4) with a linear range of 0.004-0.25 μg/mL. HRSV (A) Post-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H6) is verified not recoginized by Recombinant Mouse Anti-RSV F Antibody (5C4) (Routinely tested).

Immobilized HRSV (A) Pre-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H7) at 1 μg/mL (100 μL/well) can bind Recombinant Human Anti-RSV Antibody (AM14) with a linear range of 0.004-0.25 μg/mL. HRSV (A) Post-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H6) is verified not recognized by Recombinant Human Anti-RSV Antibody (AM14) (QC tested).

Immobilized HRSV (A) Post-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H6) and HRSV (A) Pre-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H7) at 1 μg/mL (100 μL/well) can bind Anti-RSV Fusion Protein Antibody (131-2A) with a linear range of 0.1-1 ng/mL . (Routinely tested).

Immobilized HRSV (A) Pre-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H7) at 1 μg/mL (100 μL/well) can bind Recombinant Human Anti-RSV Antibody (D25) with a linear range of 0.1-2 ng/mL. HRSV (A) Post-fusion glycoprotein F0, His Tag (Cat. No. RSF-V52H6) is verified not recoginized by Recombinant Human Anti-RSV Antibody (D25) in low concentration (Routinely tested).