An effective toxoid from tetanus toxin prepared by stepwise iodination of purified toxin.
Purified samples of tetanus toxin were gradually iodinated by stepwise addition of iodine, up to saturation. The residual capacity of each sample to provoke tetanus was tested by injecting sc 25 Lf (Limit of flocculation) in mice. Toxicity diminished in relation to iodine incorporated, and with iodine-saturated samples, doses of up to 100 Lf in mice, or 500 Lf in guinea-pigs, proved innocuous. Mice immunized with two doses of this toxoid adsorbed on Al(OH)3, and challenged with standard lethal toxin, gained protection against 10 MLD (Minimum Lethal Doses). Guinea-pigs were immunized by a single sc dose of 27.5 Lf with fluid toxoid, and all resisted challenge against 10 MLD applied 30 days later. The mice sera gave strong immunoprecipitation lines against the native toxin. The findings indicated that by controlled iodination of tetanus toxin an effective and inexpensive toxoid can be prepared.
Soares
H R
HR
Department of Physiology and Biophysics, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil.
Nunes
R L
RL
Prado
S M
SM
Higashi
H G
HG
Heneine
I F
IF
D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D002850:Chromatography, Gel; D005260:Female; D006168:Guinea Pigs; D007114:Immunization; D007455:Iodine / Q000737:chemistry*; D008297:Male; D051379:Mice; D011233:Precipitin Tests; D013744:Tetanus Toxin / Q000737:chemistry* / Q000633:toxicity; D013745:Tetanus Toxoid / Q000737:chemistry* / Q000633:toxicity
D000907:Antibodies, Bacterial; D013744:Tetanus Toxin; D013745:Tetanus Toxoid; D007455:Iodine