Immunization of the rat against taenia taeniaefomis

Abstract

In vitro products and saline soluble antigens derived from Taenia taeniaeformis metacestodes were shown to stimulate significant resistance against challenge in rats. Unless necessary, for experimental purposes, each rat was vaccinated with Img of antigen as determined by its protein content. Both antigens were effective when administered alone orally and intraperitoneally, but required adjuvants when given intramuscularly. Bordetella pertussis considerably enhanced the protective effects of the antigens when given with the intraperitoneal and intramuscular vaccinations. Aluminum hydroxide was also shown to be an adequate adjuvant. Freund's complete adjuvant was found to be ineffective in improving the resistance stimulated by either antigen. With the oral route, it was found that administration of the dose of in vitro products equally divided over five days provided significantly more resistance than giving the dose once only. Increasing the dosage of the saline soluble antigens given orally and giving the antigen at intervals over a two week period, . did not improve the resistance. B. pertussis failed to improve the resistance stimulated by orally administered saline soluble antigens, whether the adjuvant was given together with the antigen or separately in the musculature. Both antigens were shown to confer a systemic resistance when given per os. Low levels of homocytotropic antibody were detected in rats immunized intramuscularly with either antigen using B. pertussis or aluminum hydroxide as adjuvants. None was detectable in those rats immunized orally or intramuscularly using Freund's complete adjuvant with either antigen. Passive transfer of resistance was not observed in recipients of serum from rats that had been vaccinated orally or intramuscularly with either antigen employing B. pertussis as an adjuvant.