1NGESTION OF INACTWATED TIilRD STAGE LARVAE OF Angiostrongylus costaricensis DOES NOT RESULT IN DETECTABLE IIUMORAL IgG RESPONSE IN MICE

Abstract

Angiostrongylus costaricensis is a nematode parasite of wild rodents. In a previous experiment, it was demonstrated that bleach water (1.5%) eliminates the infective third stage larvae that may be present on vegetables and fruits. In that experiment, sem from mice moculated with inactivated larvae had humoral reactivity against crude antigen ofA. costaricensis detected by Westem-blot. In order to confirm and analyse this flnding, we used 3 groups of Swiss females, 8 weeks-old mice: a negative control group (NC), a positive control group (PC) and an experimental group (EG). Mice ofEG group were inoculatedper os with inactivated larvae. Afler 28 days, the mice ofPC and EG groups were moculated with 15 non-treated infective third stage larvae. No significant differences favoring a protective response were detected in the variables: survival, number ofworms, morbidity and humoral reactivity In conclusion, there were neither evidences of a strong bumoral response nor protection after oral inoculation ofinactivated A. costaricensis larvae.