Toxin tetanus

Another vaccine protein that has recently been produced in tobacco chloroplasts is the Fragment C domain of tetanus toxin (TetC). TetC is a nontoxic 47 kDa polypeptide that can induce an immune response upon 

Biopharmaceuticals in Plants Toward the Next Century of Medicine 

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Botulinum neurotoxins (A-G), tetanus toxin Synaptic peptides a) Synapto-brevin b) Syntaxin c) SNAP25 Zinc dependent endoprotease Cleavage of synaptic peptides Inhibition of transmitter release (tetanus, botulism)... 

Tetanus is a disease caused by the release of neurotoxins from the anaerobic, spore-forming rod Clostridium tetani. The clostridial protein, tetanus toxin, possesses a protease activity which selectively degrades the pre-synaptic vesicle protein synaptobrevin, resulting in a block of glycine and y-aminobutyric acid (GABA) release from presynaptic terminals. Consistent with the loss of neurogenic motor inhibition, symptoms of tetanus include muscular rigidity and hyperreflexia. The clinical course is characterized by increased muscle tone and spasms, which first affect the masseter muscle and the muscles of the throat, neck and shoulders. Death occurs by respiratory failure or heart failure. 

Tetanus (adsorbed) Cultures of Cl. tetani in liquid medium 1 Conversion of toxin to toxoid 2 Separation and purification of toxoid 3 Adsorption to adjuvant 3 + 3 quantal assay in mice using subcutaneous challenge with tetanus toxin Inoculation of guinea-pigs to exclude presence of untoxoided toxin... 

Safety tests. Beeause many vaccines are derived from basic materials of intense pathogenieity— the lethal dose of a tetanus toxin for a mouse is estimated to be 3 x 10 (ig—safety testing is of paramount importance. Effective testing provides a... 

Tetanus antitoxin Neutralization of the paralytic effect of tetanus toxin in mice 1000 lU ml for prophylaxis 3000 lU ml for treatment... 

Altered release. Tetanus is an infectious disease caused by the bacterium Clostridium tetani. This bacterium produces a neurotoxin active on inhibitory synapses in the spinal cord. Motor neurons, which supply skeletal muscle and cause contraction, have cell bodies that lie in the spinal cord. Under normal circumstances, these motor neurons receive excitatory and inhibitory inputs from various sources. The balance of these inputs results in the appropriate degree of muscle tone or muscle contraction. Tetanus toxin prevents the release of gamma amino butyric acid (GABA), an important neurotransmitter active at these inhibitory synapses. Eliminating inhibitory inputs results in unchecked or unmodulated excitatory input to the motor neurons. The resulting uncontrolled muscle spasms initially occur in the muscles of the jaw, giving rise to the expression lockjaw. The muscle spasms eventually... 

Jefferys, J. G. Whittington, M. A. (1996). Review of the role of inhibitory neurons in chronic epileptic foci induced by intracerebral tetanus toxin. Epilepsy Res. 26,... 

Bizzini, B., Blass, J., Turpin, A., and Raynaud, M. (1970) Chemical characterization of tetanus toxin and toxoid amino acid composition, number of SH and S-S groups and N-terminal amino acid. Eur. J. Biochem. 17, 100-105. 

Tetanus toxin fragment C Tobacco leaves Systemic IgG and local IgA responses. Immuno- -genic in mice when administered nasally. 113... 

Synaptobrevins (VAMPs) Synaptogyrin Synaptophysins PKA but diverge C-terminally. Synapsins Ia/b contain C-terminal phosphorylation sites for CaMKII and CDK 5. Interact with microfilaments, neurofilaments, microtubules, SH3 domains, calmodulin and annexin VI in vitro. Small-membrane proteins that are cleaved by tetanus toxin and by botulinum toxins B, D, F and G. Polytopic membrane protein that is tyrosine-phosphorylated. Function unknown. Polytopic membrane proteins, including synaptoporin, that are tyrosine-phosphorylated and bind to synaptobrevins. May regulate SNARE function... 

Price, D. L., Griffin, J., Young, A., Peck, K. and Stocks, A. Tetanus toxin direct evidence for retrograde intraaxonal transport. Science 188 945-947,1975. 

Compared to people in a noncontaminated area, plasma IgG levels were also significantly decreased in proportion to increasing plasma levels of TCDD in a cohort exposed in an industrial accident in Seveso, Italy.118 There was no effect on IgM or IgA levels, or on complement levels IgE was not measured. In separate studies, in vitro exposure to TCDD enhanced the spontaneous production of IgE by B cells isolated from atopic but not non-atopic individuals, but did not affect the levels of other isotypes.119 Other recent studies have reported small changes in immune cells from individuals exposed occupationally to PHAH.120121 For example, compared to unexposed controls, a cohort of men exposed occupationally to TCDD had diminished IFNy production in a recall response to tetanus toxin, while IFNy production following polyclonal activation was unaffected.120 This observation is consistent with mouse studies, in which antigen-specific responses are highly suppressed by TCDD, but mitogen-driven T cell responses are less susceptible to impairment.83 88122123... 

Albumin, tetanus toxin, autocrine motility factor, interleukin-2, alkaline phosphatase, glycosyl-phosphatidylinositol (GPI)-GFP, polyoma virus, and echo virus 1 (26). 

Bakry, N., Kamata, Y. and Simpson, L.L., Lectins from Triticum vulgaris and Umax flavus are universal antagonists of botulinum neurotoxin and tetanus toxin, J. Pharmacol. Exp. Ther., 258, 830-836, 1991. 

Eklund, M.W., Poysky, F.T. and Habig, W.H., Bacteriophages and plasmids in Clostridium botulinum and Clostridium tetani and their relationship to production of toxins, in Simpson, L.L., ed., Botulinum Neurotoxin and Tetanus Toxin, Academic Press, New York, pp. 25-51, 1989. 

Poulain, B., Mochida, S., Weller, U., Hogy, B., Habermann, E., Wadsworth, J. D., Shone, C.C., Dolly, J.O. and Tauc, L., Heterologous combinations of heavy and light chains from botulinum neurotoxin A and tetanus toxin inhibit neurotransmitter release in Aplysia, J. Biol. Chem., 266, 9580-9585, 1991. 

Tetanus Clostridium tetani tetanus toxin Blocks neurotransmitter release in the brain leading to chronic contraction of muscles (See Figure 13.9)... 

A second example of a toxin that has been used as targeting device is tetanus toxin. Tetanus toxin is a potent neurotoxin, which can undergo uptake in the nerve endings of motor neurones and subsequent retrograde transport into the central nervous system. The nontoxic C-fragment of tetanus toxin (TTC,451 amino acids), has been used to increase the neuronal uptake of the therapeutic protein SOD [57]. Following intravenous infusion, the recombinant hybrid protein reduced the occurrence of ischaemia-induced cerebral infarction in rats [58]. 

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