A single dose intranasal combination panebolavirus vaccine

Abstract

Abstract Background Ebolaviruses Ebola (EBOV), Sudan (SUDV) and Bundibugyo (BDBV) cause severe human disease, which may be accompanied by hemorrhagic syndrome, with high case fatality rates. Monovalent vaccines do not offer cross-protection against these viruses whose endemic areas overlap. Therefore, development of a panebolavirus vaccine is a priority. As a vaccine vector, human parainfluenza virus type 3 (HPIV3) has the advantages of needle-free administration and induction of both systemic and local mucosal antibody responses in the respiratory tract. Methods To minimize the anti-vector immunity, genes encoding the HPIV3 envelope proteins F and HN were removed from the vaccine constructs, resulting in expression of only the ebolavirus envelope protein – glycoprotein (GP). These second-generation vaccine constructs were used to develop a combination vaccine against EBOV, SUDV and BDBV. Results and Conclusions A single intranasal vaccination of guinea pigs or ferrets with the trivalent combination vaccine elicited humoral responses to each of the targeted ebolaviruses, including binding and neutralizing antibodies, as well as Fc-mediated effector functions. This vaccine protected animals from death and disease caused by lethal challenges with EBOV, SUDV or BDBV. Notably, the combination vaccine elicited protection which was comparable to that induced by the monovalent vaccines, thus demonstrating the value of this combination trivalent vaccine.