A SENSITIVE ANTIBODY-BASED METHOD FOR DETECTING CRYPTOSPORIDIUM PARVUM OOCYSTS IN WATER

摘要

A viral symbiont (CPV) of Cryptosporidium parvum and Cryptosporidium hominis sporozoites has been characterized and a CPV capsid protein, CPV40, has been identified as a target for sensitive detection of C. parvum. Recombinant CPV40 was produced in E. coli, purified by affinity chromatography, and used to prepare polyclonal rabbit sera specific for the viral capsid protein. Anti-rCPV40 recognized a 40 kDa and a 30 kDa protein in C. parvum oocysts and appeared to localize to the apical end of the parasite. Anti-rCPV40 serum was capable of detecting as few as one C. parvum or C.hominis oocyst in a dot blot assay, the sensitivity being at least 1000-fold greater than sera reactive with total native C. parvum protein or specific for the 41 kDa C. parvum oocyst surface antigen. Water samples were seeded with C parvum /i