[Biodynamics of the antigen-antibody reaction in vivo]

J M Scherrmann1

  • 1Unité 26 de l'INSERM, Hôpital Fernand Widal, Paris.

The success of the toxin neutralization by a specific antibody in a living system depends on multiple factors. First, the type of the actual available antibody structures (immunoglobulin G, Fab2 or Fab fragments) must be selected according to the toxin molecular weight: Fab is adapted to the neutralization of haptens, IgG and Fab2 to macromolecular toxins. Other factors involved in the success of immunotherapy are issued from the pharmacokinetic properties of the toxin: non reversible binding to the receptor, intracellular distribution of a macromolecular toxin are disadvantageous. Finally, the selection of the antibody dose according to its association constant value for the toxin allows to administer the optimal capacity of immunoneutralization. The control of all these factors inserted in the biodynamics of the living system contributes to the success of immunotherapy.

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