A rational design for the nanoencapsulation of poisonous animal venoms in liposomes prepared with natural phospholipids.

This study demonstrated the use of liposomes to encapsulate harmful animal venoms, specifically from the Crotalus durissimus terrificus and a range of Bothropic species. This encapsulation aimed to increase production of anti-venom antibodies in horses and mice and reduce toxicity.

Liposome Encapsulation of Venoms

• The venoms were processed and encapsulated within liposomes, which are microscopic vesicles composed of an outer lipid layer and inner spaces that can carry substances.
• This process reduces venom toxicity while promoting its recognition by the immune system, encouraging the production of anti-venom antibodies.
• Encapsulation stability was a challenge due to venom phospholipases, but was circumvented by chemically modifying the venoms.
• Modified venoms were analyzed using a number of methods including UV, CD spectroscopy, and enzyme-linked immunosorbent assay (ELISA).

Stabilization and Efficiency of Encapsulation

• To maintain the encapsulated venoms’ stability over time, mannitol, a cryoprotectant, was used.
• In this experiment, the encapsulation process was 59% efficient for Bothropic venoms (LB) and 99% efficient for Crotalus durissimus terrificus venom (LC).
• Both LC and LB were stable for 22 days at 4 °C and remained stable even after lyophilization — a freeze-drying process — as determined by the light scattering measurements.

Immunization and Anti-venom Antibody Production

• Genetically selected mice and mixed breed horses were immunized with the encapsulated venoms.
• Neither species exhibited any clinical signs of venom toxicity, demonstrating the successful inactivation of the venom toxicity by the encapsulation process.
• The horses and mice produced substantially higher (30% more) antibodies against the venoms 25 days after immunization, and the increase in total IgG (a type of antibody) levels remained high for 91 days.
• This data suggests that the liposomal encapsulation of venoms does not only reduce toxicity, but it also enhances the immune response, showing promising potential for the development of novel anti-venom therapies.