Tetanus toxin properties

The term microbial toxin is usually reserved by microbiologists for toxic substances produced by microorganisms that are of high molecular weight and have antigenic properties toxic compounds produced by bacteria that do not fit these criteria are referred to simply as poisons. Many of the former are proteins or mucoproteins and may have a variety of enzymatic properties. They include some of the most toxic substances known, such as tetanus toxin, botulinus toxin, and diphtheria toxin. Bacterial toxins may be extremely toxic to mammals and may affect a variety of organ systems, including the nervous system and the cardiovascular system. A detailed account of their chemical nature and mode of action is beyond the scope of this volume. 

Schiavo G, Papini E, Genna G, Montecucco C (1990) An intact interchain disulfide bond is required for the neurotoxicity of tetanus toxin. Infect Immun 58 4136 11 Scott AB, Magoon EH, McNeer KW, Stager DR (1989) Botulinum treatment of strabismus in children. Trans Am Ophthalmol Soc 87 174-180 discussion 180 1 Scott D (1997) Phospholipase A2 structure and catalytic properties. In Kini R (ed) Venom phospholipase A2 enzymes structure, function and mechanism. John Wiley Sons, Chichester, p 97-128. 

Compared to polyclonal antibodies, mAbs display molecular homogeneity and significantly higher specificity leading to increased in-vivo activity. For example, 100-170 mg serum containing polyclonal antibodies against the tetanus toxin are necessary to achieve the same effect as 0.7 mg of a respective mAb. This section will provide an overview on therapeutic antibodies which have either been approved or are in clinical development, and will classify them according to different pharmacodynamically relevant properties. 

Manning KA, Erichsen JT, Evinger C (1990) Retrograde transneuronal transport properties of fragment C of tetanus toxin. Neuroscience. 34 251 -63... 

When recently studied, tetanus toxin was shown to interact with thyroid plasma membranes.35 38 More important, the properties of this interaction were shown to closely resemble the properties of the TSH interaction with TSH receptors on these membranes the interaction of tetanus toxin with thyroid membranes exhibited several characteristics of its interaction with neural tissue tetanus toxin would not bind to membranes of a thyroid tumor with a TSH receptor defect and tetanus toxin could stimulate thyroid hyperfunction in mice subjected to conditions known to precipitate thyroid storm. 

Simpson, L.L., Coffield, J.A., and Bakry, N. 1993. Chelation of zinc antagonizes the neuromuscular blocking properties of the seven serotypes of botulinum neurotoxin as well as tetanus toxin. J. Pharmacol. Exp. Ther.. ... 

Property Diphtheria toxin Tetanus toxin Botulinus toxin, type A Human serum albumin ... 

Many antigens currently marketed would be inherently toxic except for the fact they have been stringently detoxified. Some of the most successful and durable vaccines today include toxoided forms of tetanus, pertussis, and diphtheria toxins. During the manufacturing process, these toxoids undergo significant chemical modifications, and their toxic properties are effectively eliminated. The safety is assured with every batch release and defined within safety charac-terization/quality control tests, which are not discussed in this chapter. 

Toxoids (or antitoxins)—A toxoid is a famed toxin which is treated chemically so that it loses the poisonous or toxic properties but still retains the power to stimulate the body cells to form the appropriate antibody. Typical toxoids are diphtheria toxoid and tetanus toxoid. 

Some of the physical and chemical properties of tetanus, botulinus, and diphtheria toxins, together with comparable data for crystalline human serum albumin, are summarized in Table II. 

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