Hapten inhibition

Hapten inhibition is used to reduce antibody-mediated reactions against larger dextran molecules.
Some individuals carry dextran-reactive antibodies that can bind multivalent dextrans such as Dextran 40 or Dextran 70. This can lead to antibody cross-linking, immune-complex formation, complement activation, and dextran-induced anaphylactoid reactions.

A low-molecular-weight dextran hapten can act as a competitive blocker by binding these antibodies before the larger dextran is administered. Given by injection into a vein shortly before a Dextran 40 or Dextran 70 plasma-volume expander, a monovalent ~1,000 Da dextran binds dextran-reactive antibodies without cross-linking them, blocking the immune-complex reaction behind dextran-induced anaphylaxis.

For this application, a tightly defined low-molecular-weight dextran fraction is essential: it must be large enough to bind dextran-reactive antibodies, but small enough to remain functionally monovalent and avoid antibody cross-linking.

Primogene’s Dextran 1 is designed for this requirement. Its very narrow and well-defined molecular-weight distribution makes it particularly suitable for hapten inhibition applications, where consistent low-MW performance, minimal higher-MW fractions, and reliable antibody-blocking behaviour are critical.