Recombinant Human ASL protein

ASGR2 (asialoglycoprotein receptor 2) is a transmembrane protein belonging to the C-type lectin superfamily, predominantly expressed on the surface of hepatocytes. It plays a critical role in glycoprotein homeostasis by recognizing and binding to desialylated (galactose-terminal) glycoproteins, triggering their endocytosis and lysosomal degradation. This receptor forms a heteromeric complex with ASGR1. enhancing ligand-binding specificity and cellular uptake efficiency. ASGR2 has garnered significant interest in biomedical research due to its liver-specific expression and potential as a therapeutic target or drug delivery vehicle.

Recombinant ASGR2 proteins are engineered to study its structural and functional properties, often produced in mammalian expression systems (e.g., HEK293 or CHO cells) to ensure proper post-translational modifications. These proteins typically include extracellular domains responsible for ligand interaction, fused with tags like Fc or His for purification and detection. Researchers utilize recombinant ASGR2 to investigate receptor-ligand interactions, screen targeted therapies, and develop liver-directed delivery systems for genes, drugs, or nanoparticles.

In clinical contexts, ASGR2 has been explored as a biomarker for liver diseases, including hepatocellular carcinoma and fibrosis. Its ability to mediate targeted internalization makes it valuable for designing ASGR2-binding ligands or antibodies in cancer therapy and antiviral strategies. Recent studies also examine its role in cholesterol metabolism regulation, potentially linking it to cardiovascular diseases. The development of recombinant ASGR2 continues to advance both basic research and translational applications in hepatology and precision medicine.

ASL (Argininosuccinate lyase) is a critical enzyme in the urea cycle, responsible for catalyzing the cleavage of argininosuccinate into arginine and fumarate. This reaction is essential for nitrogen disposal and the biosynthesis of arginine, a semi-essential amino acid. Deficiencies in ASL activity due to genetic mutations lead to argininosuccinic aciduria, a rare autosomal recessive disorder characterized by hyperammonemia, metabolic imbalance, and neurological complications. Traditional approaches to study or supplement ASL rely on isolating the enzyme from natural sources, but low abundance and purification challenges limit scalability and therapeutic applications.

Recombinant ASL protein, produced via genetic engineering, offers a sustainable and efficient alternative. By cloning the ASL gene into expression systems like *E. coli*, yeast, or mammalian cells, researchers achieve high-yield production with consistent quality. This method enables precise control over protein structure and post-translational modifications, enhancing functional fidelity. Recombinant ASL is pivotal in enzyme replacement therapy (ERT) for genetic disorders, providing a purified, bioavailable form to restore metabolic pathways. It also serves as a tool for mechanistic studies, drug screening, and diagnostic assays to evaluate urea cycle dysfunction.

Recent advancements focus on optimizing expression systems to improve protein stability and reduce immunogenicity. PEGylation and nanoparticle encapsulation are explored to prolong circulation half-life in therapeutic contexts. Additionally, recombinant ASL supports the development of gene therapies by serving as a reference for correcting enzymatic activity in cellular models. Despite progress, challenges like tissue-specific delivery and cost-effective manufacturing remain. Overall, recombinant ASL exemplifies the intersection of biotechnology and precision medicine, addressing unmet needs in rare metabolic diseases while advancing biochemical research.