Antivenoms - antibodies, resulting in serum when ingested toxins or anatoxins. Able to interact with toxins (see), neutralizing their activity. The antivenom can be synthesized as a result of natural contact of the body with toxins, artificial introduction into the organism of animals in sublethal doses and immunization by anatoxinum humans or animals. Wide application in medicine have antitoxic serum against toxins excreted pathogens (sticks diphtheria, tetanus, gas gangrene and botulism), used to prevent and treat these diseases, and vaccine against poisons snakes, insects. Antivenoms used in medical practice as antitoxic serum, produced by hyperimmunization horses increasing doses of toxins. Antivenoms against botulism and gas gangrene polyvalent, i.e. contain antibodies to multiple toxins. The power of antivenoms is measured by the number of antitoxic units (AE) in 1 ml, in a way of determining which depends on the type of antitoxin. Serum containing the antivenom, dried in a vacuum and store at low temperature. See also Antibody.

Antivenoms (from the Greek. anti - vs + toxins) antibodies, which are formed in the organism of animals and humans in response to the emergence of toxins microbial, plant or animal origin, specifically neutralize the relevant toxins and are a powerful factor antitoxic immunity (see). The most important are the antivenom, which are produced against exotoxins or soluble toxins microbial agents of the high-toxigenic diseases: diphtheria, tetanus, gas gangrene, botulism, and dysentery bacteria Grigorieva-Shiga, skarlatines Streptococcus, Staphylococcus. Antitoxic immunity may be reproduced artificially active immunization with anatoxinum (see) or passive immunization antitoxic serum.
The content of antivenoms in antitoxic serum specimen is expressed in toxic units (AE). About the tension antitoxic immunity can be judged by the content of antivenom serum. The presence in 1 ml of blood 1/30 AE diphtheria antitoxin enough to ensure the immunity of the child to diphtheria; the reaction of the Chic he will be negative. Protection against tetanus, according to Regalia (R. N. Regamey, 1965), is due to the presence in 1 ml of blood 0,005 AE tetanus antitoxin.
Antivenoms used in medical practice as antitoxic serum (diphtheria, tetanus, protivodiareynoe Grigorieva-Shiga, protivomigrenoznoe, protivopodagricescoe, protivokariosnoe, protiwastmaticescoe), which is prepared by hyperimmunization horses increasing doses of relevant toxins or anatoxins. In liquid sera antivenoms quite unstable: they are destroyed at the temperature of 100 degrees and weakened when 60-70 degrees; inactivated under the influence of the direct action of sunlight. After the freeze drying under vacuum at low temperatures A. become more stable and well preserved for many years.
1 AE A. diphtheria, on the proposal of Ehrlich (P. Ehrlich), adopted such a number of diphtheria serum, which in mixture with Lt (Limes tod) diphtheria toxin causes the death of the Guinea pig weighing 250 g within 96 hours.
Lt diphtheria toxin is set in experiments on Guinea pigs using standard of diphtheria antitoxic serum. International antitoxic units (AU) contained in certain quantities (mg) the reference sera, published by the international laboratory for biological standards serum Institute in Copenhagen. Production institutes of the USSR supplied standard antitoxic serum from the Institute of control of medical biological preparations. L. A. Tarasevich (Moscow).
Reaction flocculation was applied only to define the title of diphtheria serum (according to the latest data, the formation of flocculate in the interaction of antitoxic serum toxin should be attributed to the presence of serum side of antibodies, so the results reaction flocculation do not always coincide with the results of determination of the title A. in vivo).
Antivenoms usually associated with ' - and 2-globulins of diphtheria serum. Northrop (L. N. Northrop, 1941) insulated diphtheria antitoxin as crystal globulin (mol. weight (mol. mass) 90 500, but the chemical structure A. still remains undetermined. The digestion of pepsin molecule immune globulin is split into two halves, one of which is a passive protein - deprived antitoxic properties and easily koaguliruet warmth and the other media antitoxin is much more resistant to pepsin and warming. Based on this principle, the method of purification of antivenoms "diapers" (A... Beilinson), which resulted in their anaphylactoidnye properties (see Anaphylaxis) are attenuated. When applying treated antivenoms symptoms of serum sickness (see) are less frequent and it flows easier.
In accordance with the theory of the Board (J. Вогdet), which was confirmed in experiments with clean toxins and A., the reaction of the toxin - antitoxin proceeds according to the laws of adsorption. In the body of the patient A. neutralized only free toxin that is not already associated with sensitive fabrics. Therefore, the effectiveness of serotherapy depends on the period of application of antitoxic serum. If you suspect the disease diphtheria, tetanus, botulism, and other toxigenic infections antitoxic serum should be introduced as soon as possible to the antitoxin neutralized free toxin to commit his sensitive fabrics. It's understandable why seroprotection (see) tetanus, botulism, and other toxigenic infections is better than serotherapy (see). Marked antitoxic properties have immune serum against snake venoms.
A. store the value in the era of antibiotics, as the latter, providing a bacteriostatic effect on microbes, not neutralize their toxins. Therefore, in such diseases as diphtheria, tetanus, botulism, which is toxemia and pathological process is almost entirely due to the damaging effect of the toxin on the sensitive tissues, serotherapy specific A. certainly shown along with antibiotic therapy and other treatment modalities.
Cm. also Antibodies.