Biotinylated Heparan Sulfate 10E4 Antibody
A new tool to detect or measure HS or HSPG
Heparan sulfate (HS) is a sulfated Glycosaminoglycan (GAG) polysaccharide that is widely found on cell membranes and in the Extracellular Matrix. HS is involved in a wide range of important biological processes through specific interactions with many biologically active proteins. In particular, HS has emerged as a key factor in infection by the SARS-CoV-2 virus, which is the cause of the COVID-19 coronavirus pandemic.
As part of our wider offering for HS and GAG research, we now offer the anti-HS 10E4 monoclonal antibody in two biotinylated formats. The 10E4 antibody recognises a common epitope on HS, found across a wide range of tissues and species, making it an ideal tool to detect or measure HS or heparan sulfate proteoglycans (HSPG).
Biotin is a water-soluble B vitamin, which forms extremely strong non-covalent interactions with streptavidin on proteins, making biotinylated antibodies useful for detection of low-abundance proteins in immunological assays. The process of biotin-labeling is also frequently used as a non-radiative labeling method for proteins, and as a protein purification technique. Biotinylated antibodies offer advantages in several key applications, by cutting out the need for the use of conjugated secondary antibodies to quantify the level of detection/binding in immunological assays. For example, for 10E4:
For double and triple staining (see Fig 1 and Talsma et al 2020): Biotinylated 10E4 antibody gives labs the freedom to choose the best fluorophore (conjugated to streptavidin) to visualize HS in combination with other antigens; and reduces spend on specific secondary antibodies, which can be expensive.
For use with adult mouse samples. As the 10E4 antibody is a mouse monoclonal antibody, conjugated secondary antibodies will detect endogenous mouse immunoglobulins already present in the sample as well as the added monoclonal antibody, leading to the risk of false-positive results in experiments with adult mouse samples. Using biotinylated mouse HS 10E4 antibody and enzyme-linked streptavidin, avoids this problem.
Different labs preferred levels of biotinylation for different applications - see Fig 1, Fig 5 and Talsma et al (2020) for fluorescent staining where high-biotin format worked best; while other labs found better results staining with a low biotin format (Figs 3 - 4)
Results shared by Hiro Katagiri (NIH, USA) showed that a low biotin format worked best for antigen capture in ELISA (Fig 2).
We’ve launched two biotinylated formats of the 10E4 antibody (high and low biotin) to address this issue; along with a starter pack to allow end-users to test both formats at a reduced price per vial.