has role protective antigen role protective antigen Cryptosporidium parvum protein CP15/60 Oliver He Preparturient cows were immunized three times over a six-week period with recombinant plasmid DNA encoding the Cryptosporidium parvum CP15/60 antigen by injecting the DNA in the mammary gland. Colostrum from these cows contained Ab specific for C. parvum sporozoites and oocysts as indicated by immunofluorescence Ab (IFA) staining. Mice receiving immune colostrum showed partial protection (about 50% reduction) against intestinal C. parvum development compared to mice receiving control colostrum. This protection was evident at a challenge dose of 10^3 C. parvum oocysts per mouse [PubMed: 10392628]. protein Allen Xiang Protegen ID: 777; NCBI Nucleotide GI: 170676501; NCBI Protein GI: 170676502; NCBI Protein Accession: ACB30404.1; NCBITaxon: 5807