Native full-length human alpha-fetoprotein (AFP), purified from human cord blood by hydrophobic-interaction, ion-exchange and affinity chromatography with sulphate fractionation and MonoQ-FPLC polishing, supplied lyophilised, 0.5 mg. 95% pure, single band at 70 kDa on SDS-PAGE; donors screened HBsAg / HIV / HCV negative. The principal oncofetal serum protein and the reference biomarker of hepatocellular carcinoma, germ-cell tumours and prenatal screening. Use as an ELISA standard, immunisation antigen and assay calibrator — also available as the 0.1 mg pack cat. 858, and the matching antigen for the anti-AFP antibodies cat. 564, cat. 605 and cat. 769.
SPECIFICATIONS
Catalogue number: 858-0.5 | Product: alpha-Fetoprotein (human), full-length native protein
Source: human cord blood; donor pool screened HBsAg / HIV / HCV negative
Molecular weight: ~70 kDa (single band on SDS-PAGE)
Gene: AFP (4q11–q21) | UniProt: P02771
Aliases: alpha-fetoglobulin, aFP, hepatoma-associated fetoprotein
Purity: 95% (SDS-PAGE, single band at 70 kDa)
Format: lyophilised
Purification: hydrophobic-interaction, ion-exchange and affinity chromatography, sulphate fractionation, MonoQ-FPLC polishing
Package size: 0.5 mg (smaller 0.1 mg pack available as cat. 858)
STORAGE / RECONSTITUTION
Reconstitution: reconstitute in sterile PBS pH 7.4 at the desired protein concentration. Centrifuge the vial briefly before opening; reconstitute by gentle inversion or low-speed pipetting (do not vortex).
For ELISA coating, dilute the reconstituted protein to 1–10 µg/mL in carbonate / bicarbonate coating buffer (pH 9.6) immediately before use. For standard-curve work, prepare single-use frozen aliquots from a single reconstitution to remove between-batch curve drift. For Western-blot positive-control loading, use 25–100 ng per lane.
Shipped at ambient temperature.
Lyophilised protein: store up to 2 years at −20 °C or lower.
Reconstituted protein: store up to 6 months at −70 °C.
Avoid repeated freeze-thaw cycles.
APPLICATIONS
- ELISA / immunoassay standard for absolute quantification of serum AFP.
- Sandwich-ELISA coating antigen for the detection and characterisation of anti-AFP antibody clones — pair with cat. 564, cat. 605 or cat. 769.
- Immunisation antigen for the production of polyclonal and monoclonal anti-AFP antibodies.
- Reference protein for hepatocellular-carcinoma (HCC) biomarker assay development, including AFP-L3 lectin-affinity workflows.
- Reference protein for the development and calibration of prenatal-screening assays (maternal-serum AFP / MSAFP, amniotic-fluid AFP).
- Reference protein for germ-cell-tumour (yolk-sac / endodermal-sinus tumour) assays.
- Western-blot positive control and migration marker for AFP (~70 kDa), 25–100 ng per lane.
APPLICATION HIGHLIGHTS — HIGH-VALUE RESEARCH NICHES
- Native cord-blood protein, not a recombinant fragment: the full-length, correctly folded molecule retains the ligand-binding architecture — AFP binds fatty acids, bilirubin, retinoids, copper and oestrogens — which recombinant fragments do not reproduce.
- AFP-L1 / L2 / L3 isoform work: the native glycoprotein can be fractionated on Lens culinaris agglutinin (LCA), the basis of the AFP-L3% test used to discriminate HCC from benign liver disease.
- Peptide-library, aptamer and scFv discovery: validated as a target antigen for bead-based combinatorial screening (see Reference).
- Prenatal-screening calibration: a single well-characterised standard underpins MSAFP and amniotic-fluid assay harmonisation.
- Oncofetal biology: AFP is a tractable model for studying re-expression of fetal genes in malignancy and for immunotherapy target work.
REFERENCES
Jee JE, Ang YL, Cha J, Ang MW, Ling J, Lim J, Lee SS. Combinatorial bead-based peptide libraries improved for rapid and robust screenings. Combinatorial Chemistry & High Throughput Screening. 2014;17(6):520–530. PMID 24410000. Used human AFP (cat. 858) as the target antigen in an improved one-bead-one-compound (OBOC) combinatorial peptide-library screen, demonstrating its use as a screening antigen for the discovery of synthetic peptide binders against a clinically important tumour-marker protein.
