neutralizing antibody

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(immunology) An antibody that reduces or abolishes some biological activity of a soluble antigen or of a living microorganism.

An antibody that reduces or abolishes some biological activity of a soluble antigen or of a living microorganism. Thus, diphtheria antitoxin is a neutralizing antibody that, in adequate amounts, abolishes the pathological effects of diphtheria toxin in animals. This is only one characteristic; the other general properties of the antibody are those of the immunoglobulin family (IgG, IgA, or IgM) to which it belongs. See also Antibody; Immunoglobulin.

An antibody that reacts with an infectious agent, usually a virus, and destroys or inhibits its infectiveness and virulence.