[Influence of immunization dose schemes on the immune response to anti-tetrodotoxin vaccine].
OBJECTIVE
To study the relationship between the immune response of anti-tetrodotoxin vaccine, including its dose-response, and to select optimal immunization dose so as to enhance antitoxic effect of the anti-tetrodotoxin vaccine.


METHODS
Tetrodotoxin (TTX) was coupled to Tachypleus tridentatus hemocyanin (TTH) chemically to form artificial antigen (TTX-TTH), and with which Balb/c mice were immunized. Influence of different immunization doses [100 microg as the higher (H) and 25 microg as the lower (L) dose group] on the protective effects of TTX vaccine was compared. The quality of antisera and effects of vaccine in anti-TTX poisoning were observed.


RESULTS
The sera antibody quality increased more quickly in group L than that in group H after immunization. The dose at which the half of immunized mice survived when challenged once with TTX were 16 x LD (1 LD = 13.5 microg/kg, i.p.) in group L and 11 x LD in group H. When TTX was used time and again, the half of immunized mice could tolerate as high as 40 x LD and 22 x LD of accumulated dose, and the maximum tolerable cumulated dose was 104 x LD and 90 x LD for group L and H respectively. The scheme L was better both in antibody quality and effect of protecting against TTX toxicity than that in scheme H.


CONCLUSIONS
The experimental vaccine of TTX could effectively protect animal from TTX intoxication. The lower immunization dose in this study is selected as the optimal immunization scheme.
Xu
Qin-hui
QH
Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Bejing 100850, China.
Gao
Li-sha
LS
Rong
Kang-tai
KT
D000818:Animals; D000906:Antibodies / Q000097:blood*; D004306:Dose-Response Relationship, Immunologic; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006433:Hemocyanins / Q000276:immunology; D006737:Horseshoe Crabs; D007106:Immune Sera / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D013779:Tetrodotoxin / Q000276:immunology* / Q000633:toxicity; D018675:Toxicity Tests; D014611:Vaccination / Q000379:methods; D014612:Vaccines / Q000008:administration & dosage* / Q000276:immunology
D000906:Antibodies; D007106:Immune Sera; D014612:Vaccines; D013779:Tetrodotoxin; D006433:Hemocyanins