An antitoxin is a specialized antibody or group of antibodies that has the ability to neutralize a particular toxicant, a type of toxin produced exclusively by living organisms. Like its counterpart, the antitoxin is also produced in living organisms, which includes plants, animals, and humans. The activity of an antitoxin is similar to that of a vaccine in that the organism’s immune system is stimulated to produce a specific antitoxin in response to the presence of small amounts of a corresponding toxin.
Natural antitoxins are useful in counteracting the poisonous effects of being bitten by certain animals or insects, such as a venomous snake or spider. However, antitoxins are also effective against the toxic effects of bacteria and other microorganisms, such as Clostridium botulinum and Corynebacterium diphtheriae, which cause botulism and diphtheria, respectively. In addition, the application of an antitoxin is not limited to being an after-the-fact treatment and may be used as a preventative measure against disease in an otherwise healthy organism.
Disease prevention through the use of natural antitoxins is commonplace in the management of livestock, such as cows, goats, and sheep. This practice most often applies to animals that have not been previously vaccinated against a disease, or in the case of the animal’s immunization record being unknown. Furthermore, the most common antibody utilized for this purpose in husbandry is tetanus antitoxin. Conditions under which this antitoxin may be given in addition to those already cited include an injury where the wound is suspected of coming into contact with contaminated soil, or following tail docking or castration. In humans, however, the transmission of antitoxins from one individual is far less practical and full of potential risk.
This leads one to wonder how a counteractive antitoxin can be produced to benefit a human, particularly one who has been infected with a toxin. Fortunately, nature’s design not only makes it possible for antitoxins to be produced internally by living creatures, but also permits them to be transferred from one to another by injection. The host of choice is usually a horse, which is injected with the toxic substance in question in gradually increasing increments. This does not harm the animal in any way. Instead, the horse produces the appropriate antibodies, which can then be donated to a human being to launch what is known as passive immunity against the invading toxin.
There is one caveat to this process, though. Passing antibody proteins from horse to man may invoke an illness known as serum sickness, also known as immune complex disease. Symptoms typically appear within one to three weeks and include nausea, joint pain, swelling of the lymph nodes, and redness around the injection site. This occurs when immune complexes, which are composed of antibody proteins and toxin antigens bound to each other, accumulate and collect in the bloodstream and organs and trigger an inflammatory response. However, unless the person suffers from impaired immunity, the body targets and destroys these deposits within a relatively short time, permitting a full recovery.