Antitoxinas

Antitoxinas, commonly referred to in English as antitoxins, are substances that neutralize biological toxins. In immunology, the term typically refers to antibodies or immune globulins produced to bind and inactivate toxins produced by bacteria, venoms, or other pathogens. By binding the toxin, antitoxins block its interaction with target cells, inhibit enzymatic activity, and promote clearance by the immune system. They can provide immediate, but temporary, protection or treatment, as opposed to vaccines that induce long-lasting immunity.

Antitoxins are produced for passive immunization. They may be derived from humans (human immune globulins obtained from plasma donors who have immunity to a specific toxin) or from animals (commonly horses) that have been immunized; purification and, in some cases, monoclonal antibodies are used. Products are widely known by specific names such as diphtheria antitoxin, tetanus immunoglobulin, and botulism immune globulin. A related concept is antivenom, which is an antitoxin against venom toxins from snakes or other creatures, typically produced by immunizing animals and purifying the antibodies.

Clinical use typically follows toxin exposure or early signs of toxin-mediated disease. Historically, diphtheria antitoxin and tetanus immunoglobulin have saved lives; botulism antitoxin products may halt progression in suspected or confirmed cases, with infant botulism treated using specialized human-derived immunoglobulin. Safety concerns include the risk of allergic reactions and serum sickness; modern preparations favor human-derived or recombinant antibodies to reduce adverse reactions and improve availability.

Historically, the antitoxin concept emerged in the late 19th century with Emil von Behring and Shibasaburo Kitasato, leading to the first serum therapies and a Nobel Prize in 1908.