Adjuvanted Fusion Protein Vaccine Induces Durable Immunity to IOnchocerca volvulus/I in Mice and Non-Human Primates

• Published in: Vaccines (Basel) 2023-07, Vol.11 (7)
• Main Authors: Ryan, Nathan M, Hess, Jessica A, Robertson, Erica J, Tricoche, Nancy, Turner, Cheri, Davis, Jenn, Petrovsky, Nikolai, Ferguson, Melissa, Rinaldi, William J, Wong, Valerie M, Shimada, Ayako, Zhan, Bin, Bottazzi, Maria Elena, Makepeace, Benjamin L, Gray, Sean A, Carter, Darrick, Lustigman, Sara, Abraham, David
• Format: Article
• Language: English
• Subjects: Design and construction; Evaluation; Immunity; Vaccines
• ISSN: 2076-393X; 2076-393X
• DOI: 10.3390/vaccines11071212

Onchocerciasis remains a debilitating neglected tropical disease. Due to the many challenges of current control methods, an effective vaccine against the causative agent Onchocerca volvulus is urgently needed. Mice and cynomolgus macaque non-human primates (NHPs) were immunized with a vaccine consisting of a fusion of two O. volvulus protein antigens, Ov-103 and Ov-RAL-2 (Ov-FUS-1), and three different adjuvants: Advax-CpG, alum, and AlT4. All vaccine formulations induced high antigen-specific IgG titers in both mice and NHPs. Challenging mice with O. volvulus L3 contained within subcutaneous diffusion chambers demonstrated that Ov-FUS-1/Advax-CpG-immunized animals developed protective immunity, durable for at least 11 weeks. Passive transfer of sera, collected at several time points, from both mice and NHPs immunized with Ov-FUS-1/Advax-CpG transferred protection to naïve mice. These results demonstrate that Ov-FUS-1 with the adjuvant Advax-CpG induces durable protective immunity against O. volvulus in mice and NHPs that is mediated by vaccine-induced humoral factors.