VACCINATION WITH ALUM-PRECIPITATED RECOMBINANT ANCYLOSTOMA-SECRETED PROTEIN-1 PROTECTS MICE AGAINST CHALLENGE INFECTIONS WITH INFECTIVE HOOKWORM (ANCYLOSTOMA-CANINUM) LARVAE

Ancylostoma-secreted protein 1 (ASP-1) is the major protein secreted b y infective hookworm larvae (Ancylostoma caninum). The Escherichia col i-expressed recombinant protein was evaluated as a vaccine antigen in a mouse model of ancylostomiasis, A. caninum larvae migrate through mo use lungs, with maximal migration occurring 48-54 h after oral infecti on. Quantitative larval recovery from the lungs at this time was used as an end point for vaccine evaluation. All mice developed antibodies to recombinant ASP-1 (rASP-1) after immunization and boosting with the alum-precipitated protein. The immunized mice had their worm burden r educed 79% (P < .0001) compared with controls. immunization with rASP- 1 in the presence of Corynebacterium parvum adjuvant also showed a vac cine effect (63% protection; P < .0001). The possibility that this pro tective effect resulted from delayed larval lung entry was excluded. r ASP-1 offers promise as a hookworm vaccine antigen.