[Hapten inhibition: inhibition of antibody dependent dextran side effects by means of low molecular dextran (dextran 1) as a monovalent hapten].

Dextran-induced anaphylactoid reactions can be attributed to preformed circulating antibodies cross-reacting with dextrans. Therefore, after intravenous administration of clinical dextran, formation of immune complexes with resulting complement activation and secondary formation and/or release of mediators with clinical symptoms of an immune complex or aggregate anaphylaxis can occur (type-III immune reaction). Antigen antibody reactions can be prevented if the antigen-binding sites of the antibodies are specifically blocked by monovalent haptens (low molecular non-immunogenic antigens). The effectiveness of this principle of 'hapten inhibition' could be proven in vitro as well as in animal experiments. In volunteer studies intravenous administration of the low molecular dextran in a 15% solution (Dextran 1), with a molecular weight around 1,000 functioning as monovalent hapten, was well tolerated.