新品来袭：荧光融合的Claudin18.2全长膜蛋白

Claudin18.2是当下最热门的靶点之一，针对该靶点开发的创新药包括单抗、双抗、CAR-T、ADC四种。

Claudin18.2是四次跨膜蛋白，属于Claudins蛋白家族，该家族是一类存在于上皮和内皮紧密连接中的整合素膜蛋白，是构成紧密连接最关键的蛋白之一，能够有效维持上皮细胞和内皮细胞的极性。Claudins蛋白家族的主要功能是调节屏障结构的渗透性。

Claudin18.2是一种胃特异性的紧密连接蛋白，在许多癌症中都有表达，尤其高表达于消化系统恶性肿瘤，包括胃癌（70%），胰腺癌（50％），食管癌（30％）等。在肿瘤中，Claudin18.2参与肿瘤细胞的增殖分化和迁移。

Claudin18.2只在癌细胞中广泛表达使得它成为一个理想的肿瘤免疫靶点。

01缔码全长Claudin18.2蛋白

针对Claudin18.2，缔码生物利用公司的全长多跨膜蛋白表达平台：VLP和Synthetic Nanodisc，基于哺乳动物表达系统，成功表达功能性Claudin18.2全长多跨膜蛋白，并经过ELISA或流式分析验证，表明我们的Claudin18.2全长蛋白产品具有天然活性和构象，可以与相应单克隆抗体特异性结合。

02应用场景 抗体筛选

Claudin18.2全长蛋白具有优异的免疫原性，可筛选出更多表位的抗体

 功能检测

Claudin18.2全长蛋白可用于抗体或配体亲和力检测（ELISA）

 CAR-T阳性率检测

Claudin18.2全长蛋白可与该靶标的CAR-T细胞表面的scFv结合，检测CAR-T阳性率

03产品列表

04验证数据 Claudin18.2-EGFP蛋白（VLP）

Figure 1. ELISA plates were pre-coated with 0.5μg/per well purified human CLDN18.2-EGFP-VLP. Serial diluted Anti-CLDN18.2 monoclonal antibody (BME100075) solutions were added, washed, and incubated with secondary antibody before ELISA reading. From above data, the EC50 for anti- CLDN18.2 monoclonal antibody binding with CLDN18.2-EGFP-VLP is 877.5ng/ml.

Figure 2. FACS analysis of CLDN18.2 VLP

A. Negative Control 1: Expi293 cells were stained with Fluorescent Human CLDN18.2 Full Length Protein-VLP (EGFP).

B. Negative Control 2: Anti-GPRC5D-CAR-Expi293 cells (an irrelevant CAR) were stained with Fluorescent Human CLDN18.2 Full Length Protein-VLP (EGFP).

C. Positive Control: Anti-CLDN18.2-CAR-Expi293 cells were stained with biotin labeled Protein L, followed by streptavidin-APC antibody.

D. Anti-CLDN18.2-CAR-Expi293 cells were stained with Fluorescent Human CLDN18.2 Full Length Protein-VLP (EGFP).

 Claudin18.2蛋白（VLP）

Figure 1. Elisa data: ELISA plates were pre-coated with 0.5ug/per well purified human Claudin 18.2 VLP. Serial diluted Anti-Claudin18.2 monoclonal antibody (Zolbetuximab biosililar; IMAB362) solutions were added, washed, and incubated with secondary antibody before ELISA reading. From above data, the EC50 for IMAB362 binding with Claudin18.2 is 15.37ng/ml.

Figure 2. Flow virometry analysis of Claudin18.2-VLP particles

1. Negative Control 1: Claudin18.2 VLP samples were stained only with Goat anti-human IgG Fc-PE secondary antibody.

2. Negative Control 2: Control VLP samples were stained with anti-Claudin18.2 antibody（Zolbetuximab biosililar; IMAB362）at 1ug/mL, followed by Goat anti-human IgG Fc-PE secondary antibody.

3. Negative Control 3: Claudin18.2 VLP samples were stained with anti-BCMA antibody（an irrelevant antibody）at 1ug/mL, followed by Goat anti-human IgG Fc-PE secondary antibody.

4. Claudin18.2 VLP samples were stained with anti-Claudin18.2 antibody（Zolbetuximab biosililar; IMAB362）at 1ug/mL, followed by Goat anti-human IgG Fc-PE secondary antibody.

 Claudin18.2蛋白（Synthetic Nanodisc）

Figure 1. Elisa plates were added with Flag Tag CLDN18.2-Nanodisc (0.2μg/per well) on an anti-Flag monoclonal antibody pre-coated (0.2μg/per well) plate. Serial diluted anti- CLDN18.2 monoclonal antibody (BME100075) solutions were added, washed, and incubated with secondary antibody before Elisa reading. From above data, the EC50 for anti- CLDN18.2 monoclonal antibody binding with CLDN18.2-Nanodisc is 593.6ng/ml.

Figure 2. Human CLDN18.2-Nanodisc, Flag Tag on SDS-PAGE