Figure 5.

Protective capacity of MERS-CoV MPSP vaccines against upper respiratory tract infection in rabbits. Six groups of vaccinated and control rabbits (n = 5/group) were tested for the presence of viral RNA (A, C) and infectious virus particles (B, D) in the upper respiratory tract (nasal swabs) at days −3 and 1–4 post intranasal viral challenge (days 46 and 50–53 post first vaccination) with 10⁶ TCID₅₀ MERS-CoV EMC strain. Shown is the average ± s.e.m. of five animals per group. The dotted lines represent the limits of detection. HR2, hepad repeat 2; FP, fusion peptide; LS, lumazine synthase 60-meric particles; I3, I3-01 60-meric particles; RBD, receptor binding domain; RBD + LS, monomeric uncoupled RBD; RBD-LS, multimeric RBD coupled to LS through covalent SpyTag/SpyCatcher.