Sj-p80

**Sj-p80** is the recombinant ~80 kDa large subunit of the calcium-activated neutral protease (calpain) from *Schistosoma japonicum*, developed as a low-cost transmission-blocking veterinary vaccine antigen for Asiatic schistosomiasis. Produced via prokaryotic expression in *E. coli* with scalable purification processes achieving up to >99% purity at four levels, it is formulated with adjuvants like Montanide ISA61 VG for intramuscular administration. In mouse challenge models, immunization reduced adult worm burden by up to 46.1%, liver egg deposition by 23.4–51.4%, intestinal egg load by 1.9–55.1%, and egg hatching by up to 31.6%, demonstrating prophylactic efficacy and immunogenicity with robust antibody titers.[1][5]