Blood Group Products
Market leading products for use in the blood product industry
ABO BLOOD GROUPS
The discovery of the ABO blood typing system by Karl Landsteiner over 100 years ago and the subsequent elucidation of their carbohydrate structures by Walter Morgan are exceedingly important milestones in the progression of modern medicine. The ABO system is the most important of the many blood typing systems and is of the utmost importance in transfusion and transplantation medicine. If patients receive a transfusion of incompatible blood, an acute haemolytic reaction can occur, potentially leading to death.
The blood group antigens are oligosaccharides expressed on the surface of red blood cells and are determined by the terminal saccharides. The biosynthesis is effected via the action of the A or B glycosyltransferase on the H antigen, to form the A or B glycan. The H antigen remains unmodified in individuals lacking either of these glycosyltransferases, resulting in an individual with blood type O. The expression of these antigens is not limited to red blood cells and also occurs on epithelial and other cells.
Blood groups are determined by the ABO gene, which encodes the glycosyltransferase which forms the A, B and H antigens. The alleles for the A and B blood types show co-dominance, whilst the blood group O allele is recessive, giving rise to the 4 familiar ABO blood types.
The AFFINDEXTM columns comprise our HAEMODEXTM A and B trisaccharides linked to Sepharose FF or 4B for use as affinity matrices in research applications. The oligosaccharides are covalently linked to the polysaccharide gel via a 10-atom spacer to overcome steric hindrance. A loading of 0.6 μmole/mL is generally found to be sufficient, with little benefit seen from higher loadings. AFFINIDEXTM columns can be used to:
- Remove anti-A and anti-B antibodies
- Study polymorphism
- Measure ligand density by lectin binding
- Clean up serum samples
- Purify antibodies
These gels will bind anti-A and anti-B antibodies (haemagglutinins) from plasma or plasma derived products. The bound antibodies can also be recovered by subsequently washing the gels with a concentrated or low pH buffer (such as 0.1 M glycine-HCl pH 2.2) and fully washed gels can be re-used. We recommend storing the products in a bacteriostatic medium such as phosphate buffered saline containing 0.02% sodium azide. Our standard pack sizes are 1 mL, 5 mL, however larger pack sizes are available on request. If you require a specific affinity matrix or alternative oligosaccharide please contact us, as custom columns are available.
Dextra Laboratories Ltd
At Dextra, we have proven expertise in the manufacture of a wide variety of blood group products, from the standard blood group oligosaccharides, to those functionalised with a selection of linker arms. To complement our free sugar range we also have the capability to produce these antigens as bioconjugates to a range of solid supports, proteins and lipids.
Our HAEMODEXTM and AFFINIDEXTM product ranges are ideally suited for use across a wide variety of research applications and we hold many of these items in stock for immediate purchase from our catalogue range. However, we are also able to fulfil custom requirements across all the blood group product ranges.
We have developed analytical methodology to support the manufacture and assure the quality of these products. We have a proven track record in scaling processes from milligram up to several kilograms through to cGMP manufacture of APIs in our state of the art, class 100,000 clean rooms. Dextra has successfully achieved ISO9001:2008 registration for all our activities.