Recombinant Human Claudin-6 (CLDN6)-VLPs, Fluorescent (Active)

This virus-like particle (VLP) formulation of recombinant human CLDN6 protein (amino acids 1-220) is expressed in mammalian cells with a C-terminal EGFP tag, combining structural authenticity with enhanced detection capabilities. The recombinant CLDN6 protein exhibits high antigenicity, demonstrated by specific binding to anti-CLDN6/9 antibody (CSB-RA005508MA1HU) in ELISA (EC₅₀: 0.5574–0.7361 ng/mL at 10 μg/mL immobilization). The mammalian expression system ensures proper folding and post-translational modifications critical for CLDN6's role in tight junction formation and cellular adhesion. As a VLP, it preserves multi-epitope presentation and is ideal for microbiological studies investigating host-pathogen interactions or microbial adhesion mechanisms. The EGFP tag enables real-time tracking in cellular assays without compromising protein function. Presented as lyophilized powder, this CLDN6 VLP serves as a versatile tool for studying microbial invasion pathways and exploring CLDN6's involvement in infection models. Its stable formulation and native-like conformation make it particularly valuable for vaccine research targeting claudin-expressing pathogens.

CLDN6 is a member of the claudin family of tight junction proteins, which are integral membrane proteins playing significant roles in maintaining the structural and functional integrity of epithelial barriers. In humans, CLDN6 is predominantly expressed during embryonic development, particularly in fetal stomach, pancreas, lung, and kidney tissues, but exhibits limited expression in healthy adult tissues, thus categorizing it as an oncofetal protein [1][2]. This characteristic positions CLDN6 as a potential biomarker for various cancers, as its expression is upregulated in several tumor types, including gastric, esophageal, and endometrial cancers [3][4][5][6].

Research indicates that elevated levels of CLDN6 correlate with poor prognosis in various malignancies. For instance, studies have shown that CLDN6 promotes tumor cell proliferation, invasion, and metastasis in gastric cancer, suggesting its role as a tumor promoter [5][7]. In endometrial carcinoma, the expression of CLDN6 is linked to a more aggressive cancer phenotype, further emphasizing its oncogenic potential [6][7]. Conversely, there are instances where CLDN6 has been observed to inhibit metastasis, indicating a paradoxical role in cancer biology wherein it may function as both a suppressor and promoter depending on the cellular context [6][8].

Mechanistically, the involvement of CLDN6 in tumor progression has been attributed to its interactions with signaling pathways such as the PI3K/Akt/mTOR pathway, which regulates cell survival and growth [7][9]. Studies have shown that the knockdown of CLDN6 diminishes cancer cell proliferation and migration, demonstrating its importance in cancer metastasis [7]. Additionally, CLDN6 has been implicated in the infection process of the hepatitis C virus (HCV), serving as an alternative receptor alongside CLDN1, underscoring its significance in both cancer and virology [10][11].

In therapeutic research, CLDN6 has emerged as a promising target for immunotherapy. The development of monoclonal antibodies and T-cell-engaging bispecific antibodies targeting CLDN6 is ongoing, with preclinical studies showing promising results in cancer models. This highlights a potential for CLDN6 to not only serve as a biomarker but also as a target for innovative targeted approaches to cancer treatment [2][12][13].

References:
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