Guanylyl cyclase C (GUCY2C) is a transmembrane protein belonging to the receptor guanylyl cyclase family. Upon activation by Escherichia coli heat-stable enterotoxin, guanylin, and uroguanylin, it transmits extracellular signals to intracellular compartments, participating in the regulation of intestinal functions. GUCY2C is expressed in primary colorectal cancer cells, with levels 2 to 10 times higher in metastatic colorectal cancer cells compared to normal intestinal epithelial cells. It is also expressed in lymph nodes and liver tissues with colorectal cancer metastases. Additionally, GUCY2C is expressed in 60% of pancreatic, gastric, and esophageal cancers, indicating its potential as a therapeutic target for these diseases. Due to its intestinal tissue specificity, GUCY2C can serve as a tumor-specific antigen for colorectal cancer, making it an ideal target for solid tumor immunotherapy. FITC-labeled GUCY2C His-tagged protein can be used for quantitative detection of GUCY2C protein expression levels and binding activity, providing a technical tool for solid tumor immunotherapy research.
To date, the biological characteristics of GUCY2C have been applied in immunotherapies such as vaccines, immunotoxins, and CAR-T cells. A U.S. research team developed an adenovirus vector vaccine, Ad5-GUCY2C-PADRE, for colorectal cancer and completed a Phase I clinical study evaluating the vaccine in early-stage colorectal cancer patients. Results showed that all vaccinated patients completed the study without any Grade 1 or higher adverse events. Antibody responses against GUCY2C were detected in 10% of patients, while 40% exhibited GUCY2C-specific T-cell responses. This study demonstrates that GUCY2C-targeted vaccines have excellent safety and immunogenicity, providing important evidence for GUCY2C-targeted immunotherapy. In vaccine development, measuring post-vaccination anti-GUCY2C antibody levels is crucial for evaluating vaccine efficacy, where GUCY2C protein serves as a positive control and ELISA coating antigen. FITC-labeled GUCY2C His-tagged protein can standardize detection processes and improve result reproducibility.
While CAR-T cell therapy has achieved success in hematologic malignancies, its application in solid tumors faces challenges due to the difficulty in identifying targets absent from normal tissues. Fortunately, GUCY2C's intestinal tissue specificity makes it a promising tumor-specific antigen for colorectal cancer. Research teams have focused on GUCY2C-targeted CAR-T studies, with findings published in Cancer Immunology Research. Results showed significant tumor reduction and 100% survival in human colorectal tumor mouse models treated with CAR-T cells. In lung metastasis models, all CAR-T-treated mice survived during a 100-day observation period without tumor metastasis. These results suggest GUCY2C-targeted CAR-T therapy may be an effective clinical approach for high-mortality colorectal cancer. In CAR-T product development, GUCY2C protein is used to measure lentiviral titers, CAR gene transfection/transduction efficiency, and CAR-positive rates—a mandatory quality control parameter.
In early 2020, preclinical research on GUCY2C-CD3 bispecific antibodies gained widespread attention. These antibodies simultaneously bind GUCY2C and CD3 on T cells, redirecting T cells to GUCY2C-positive tumor cells to mediate specific cytotoxicity. This strategy activates patients' own T cells to kill tumors without requiring ex vivo genetic modification, offering greater convenience and accessibility. Preclinical studies demonstrated potent antitumor activity of GUCY2C-CD3 bispecific antibodies in colorectal cancer models, providing new treatment options for GUCY2C-positive solid tumor patients. FITC-labeled GUCY2C His-tagged protein can assess bispecific antibody binding capacity and validate functional activity.
GUCY2C protein plays critical roles in quality control during drug and cell therapy development. In CAR-T products, it measures lentiviral titers and CAR gene delivery efficiency. In antibody development, it screens high-affinity antibodies and evaluates binding activity/specificity. In vaccines, it serves as both immunogen and detection antigen. Various tagged GUCY2C recombinant proteins (Fc/His tags) support these applications. FITC-labeled GUCY2C His-tagged protein enables flow cytometry analysis of CAR-T antigen-binding activity, providing standardized quality control tools.
Nanjing UA-BioTech Co., Ltd. (UA-Bio) has independently developed "FITC Labeled-GUCY2C His Tag Protein, Human" (Catalog #: UA011255), a high-performance green fluorescent probe specifically designed for guanylyl cyclase C (GUCY2C) targeting research and colorectal cancer immunotherapy evaluation. GUCY2C is a receptor guanylyl cyclase expressed on intestinal mucosal epithelial cells and stably overexpressed in colorectal cancer cells, making it a highly promising tumor-specific target. This product consists of the human GUCY2C extracellular domain with His tag and FITC labeling, enabling efficient binding with anti-GUCY2C antibodies or affinity ligands. It provides a stable, reliable standardized tool for CAR-T therapy evaluation, antibody drug screening, colorectal cancer biomarker research, and related fields.
| Core Advantages | Detailed Parameters / Functional Description |
|---|---|
| High Purity & Intact Bioactivity | Produced using advanced eukaryotic expression systems and standardized purification processes, the product undergoes multidimensional quality control to ensure >95% purity and correct native conformation (with intact glycosylation). Optimized FITC labeling preserves high antibody-binding affinity, accurately mimicking GUCY2C's antigenic properties on colorectal cancer cells. |
| High-Brightness FITC Labeling | Employing optimized FITC labeling ratios, each GUCY2C molecule carries stable fluorophore counts, emitting bright green fluorescence under 488 nm excitation. Ideal for flow cytometry (FACS) and fluorescence microscopy, ensuring reliable evaluation and quantification of GUCY2C-targeting molecules. |
| Exceptional Batch Consistency & Stability | Rigorous quality management from expression to purification, combined with comprehensive release testing, guarantees consistent binding activity, uniform fluorescence intensity, and excellent long-term stability. Provides solid reliability for continuous GUCY2C-targeted research. |
| Versatile Application Tool | Excels in multiple applications: CAR-T cell positivity rate detection by flow cytometry, anti-GUCY2C antibody/antagonist screening, competitive binding assays, colorectal cancer biomarker analysis, and more. Widely applicable to GUCY2C-targeted CAR-T product development, diagnostic tool research, and drug activity evaluation. |
| Complete Solutions & Professional Support | Provides validated protocols, representative flow cytometry data, and detailed interpretation guidelines to help establish reproducible GUCY2C detection workflows. Nanjing UA-Bio's technical team offers end-to-end consulting for experimental design, optimization, and data analysis. |
Nanjing UA-BioTech Co., Ltd. is dedicated to providing cutting-edge, high-quality core reagents and tools for immunology, cell therapy, and innovative drug development. For detailed technical parameters, validation data, or application consultations regarding "FITC Labeled-GUCY2C His Tag Protein, Human" (Catalog #: UA011255), please contact us anytime.
