Purified Immunoglobulin F(ab′)2 Protects Mice and Rhesus Monkeys against Lethal Ricin Intoxication

Objective: Ricin is a highly toxic ribosome-inactivating lectin derived from castor beans. To date, no antidote available to treat ricin-poisoned patients, and the development of safe effective urgently needed. Methods: First, ricin was prepared used construct mouse model rhesus monkey intoxication. Second, pepsin-digested F(ab′) 2 fragments serum IgG horses injected with Freund’s-adjuvanted purified were prepared. Third, protective efficacy evaluated in models lethal Results: The purity quotient exceeded 90% 85% models, respectively. LD 50 mice monkeys 2.7 9 μg/kg, A quantity 6.25 1.85 mg/kg sufficient intoxication monkeys, Finally, effect this therapeutic antibody on peripheral blood immune cells examined by analysis through single cell sequencing. underlying mechanism found involve restraining neutrophil activation, proliferation, differentiation. Conclusion: Purified administered needle-free devices fully protect against doses