Asialofetuin from Fetal Calf Serum (Type I) – Research Use Only

Asialofetuin from Fetal Calf Serum (Type I) is a desialylated form of fetuin in which terminal sialic acid residues have been removed, exposing underlying galactose and N-acetylgalactosamine moieties. Supplied as a 50 mg high-purity lyophilized powder, this biotechnology-grade glycoprotein is a valuable research tool for studying asialoglycoprotein receptor (ASGPR)-mediated endocytosis, lectin binding, glycan-dependent clearance mechanisms, and the functional consequences of terminal sialylation in biological systems.

Scientific Overview

Fetuin is a major glycoprotein in fetal calf serum that carries multiple sialylated N- and O-linked glycans. Removal of terminal sialic acid residues generates asialofetuin, exposing penultimate galactose and N-acetylgalactosamine residues. This structural change dramatically increases binding affinity to the asialoglycoprotein receptor (ASGPR) on hepatocytes and alters interactions with various lectins (e.g., RCA, PNA). Asialofetuin is therefore a classic tool for investigating receptor-mediated endocytosis, glycan-dependent clearance, lectin specificity, and the biological consequences of desialylation.

This Asialofetuin from Fetal Calf Serum (Type I) is suitable for:

• Asialoglycoprotein receptor (ASGPR) binding and endocytosis studies
• Lectin-binding assays and glycan profiling
• Investigation of sialylation effects on glycoprotein half-life and clearance
• Cell signaling and differentiation studies modulated by desialylated glycoproteins
• Development of glycoprotein-based competitors or standards in biochemical assays

Usage & Handling Guidance

Store the lyophilized powder at 2–8 °C. Reconstitute in ultrapure water or desired buffer (e.g., PBS or Tris-HCl) to the required concentration. Prepare fresh working solutions or single-use aliquots. The desialylated form is stable but should be protected from repeated freeze–thaw cycles if reconstituted.

• Recommended applications: Receptor binding, lectin assays, endocytosis studies, and glycan research
• Working concentration: Optimize empirically (typically 0.1–10 mg/mL depending on the assay)
• Solubility: Highly soluble in aqueous buffers
• Handling: Use in a clean environment; avoid conditions that may cause aggregation

What You Get

• 50 mg Asialofetuin from Fetal Calf Serum (Type I) as a high-purity lyophilized powder
• Desialylated glycoprotein with exposed terminal galactose residues
• Biotechnology-grade reagent suitable for precise glycobiology and receptor studies
• Batch-specific documentation available upon request
• For research use only (RUO)

Why Researchers Choose It

• Well-defined desialylated fetuin with exposed galactose/N-acetylgalactosamine residues
• Classic ligand for studying asialoglycoprotein receptor (ASGPR)-mediated endocytosis
• Excellent tool for lectin specificity, glycan profiling, and sialylation research
• Stable powder format for convenient reconstitution in experimental buffers
• High-purity biotechnology-grade material prepared with ultrapure water and sterile filtration

Frequently Asked Questions (FAQ)

• What does “asialofetuin” mean?
  It is fetuin from which terminal sialic acid residues have been enzymatically or chemically removed, exposing underlying galactose residues.
• What is the primary research use?
  It is a standard ligand for the asialoglycoprotein receptor (ASGPR) and a tool for studying glycan-dependent clearance, lectin binding, and sialylation effects.
• How should I reconstitute the powder?
  Reconstitute in ultrapure water or PBS to the desired concentration. Prepare aliquots if not using immediately.
• Is this suitable for cell culture experiments?
  Yes. It is commonly added to culture media to study receptor-mediated uptake or to compete with endogenous glycoproteins.
• Does this product contain sialic acid?
  No. As “asialo-” indicates, terminal sialic acids have been removed (Type I preparation).

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References

• shwell G, Harford J. Carbohydrate-specific receptors of the liver. Annu Rev Biochem. 1982;51:531-554.
• Stockert RJ. The asialoglycoprotein receptor: relationships between structure, function, and expression. Physiol Rev. 1995;75(3):591-609.
• Weigel PH, Yik JH. Glycans as endocytosis signals: the cases of the asialoglycoprotein and hyaluronan/chondroitin sulfate receptors. Biochim Biophys Acta. 2002;1572(2-3):341-363.
• Simpson DL, et al. Killing of cultured hepatocytes by conjugates of asialofetuin and the A chains of ricin or diphtheria toxin. Cell. 1982;29(2):469-477.
• Saunier B, et al. Role of the asialoglycoprotein receptor in binding and entry of hepatitis C virus structural proteins in cultured human hepatocytes. J Virol. 2003;77(1):546-559.
• D'Souza AA, Devarajan PV. Asialoglycoprotein receptor mediated hepatocyte targeting - strategies and applications. J Control Release. 2015;203:126-139.
• Sakwe AM, et al. Fetuin-A (α2HS-glycoprotein) is a major serum adhesive protein that mediates cell attachment and spreading. Cell Mol Life Sci. 2010;67(24):4213-4223.
• Nangami GN, et al. Fetuin-A (alpha 2HS glycoprotein) modulates growth, motility, and invasion in high-grade astrocytoma cell lines. Cancer Med. 2016;5(12):3548-3559.
• Černocká H, et al. Fetuin and asialofetuin at charged surfaces: Influence of sialic acid. Bioelectrochemistry. 2021;142:107932.
• Plank C, et al. Gene transfer into hepatocytes using asialoglycoprotein receptor mediated endocytosis of DNA complexed with an artificial tetra-antennary galactose ligand. Bioconjug Chem. 1992;3(6):533-539.
• Ashwell G, Harford J. Carbohydrate-specific receptors of the liver. Annu Rev Biochem. 1982;51:531-554.
• Stockert RJ. The asialoglycoprotein receptor: relationships between structure, function, and expression. Physiol Rev. 1995;75(3):591-609.
• Weigel PH, Yik JH. Glycans as endocytosis signals: the cases of the asialoglycoprotein and hyaluronan/chondroitin sulfate receptors. Biochim Biophys Acta. 2002;1572(2-3):341-363.
• Simpson DL, et al. Killing of cultured hepatocytes by conjugates of asialofetuin and the A chains of ricin or diphtheria toxin. Cell. 1982;29(2):469-477.
• Saunier B, et al. Role of the asialoglycoprotein receptor in binding and entry of hepatitis C virus structural proteins in cultured human hepatocytes. J Virol. 2003;77(1):546-559.
• D'Souza AA, Devarajan PV. Asialoglycoprotein receptor mediated hepatocyte targeting - strategies and applications. J Control Release. 2015;203:126-139.