Fig. 5. IgG elicited by LION/repRNA encoding gH/gL protects humanized mice from lethal EBV challenge.

a Humanized mice received IgG via intraperitoneal injection that was harvested from one of three groups: mice immunized with gH/gL protein, mice immunized with LION/repRNA encoding gH/gL, or unimmunized control mice. 24 h later, mice were bled and challenged with EBV, bled weekly starting 2 weeks post-challenge, and then euthanized at week 12 or earlier if humane endpoints were met. Created using BioRender.com. Reciprocal endpoint titers of gH/gL binding (b) and total IgG (c) were measured at the time of challenge. Each dot represents an individual mouse (n = 4 repRNA IgG, n = 5 Protein IgG and Control IgG), the horizontal bars represent the means, and the error bars represent the standard deviation in (b) and (c). d Survival of mice after challenge. Significant differences between each group and the IgG control were determined using a log-rank Mantel-Cox test. Viral DNA in the peripheral blood of control mice (e) and mice that received passive transfer of repRNA/LION gH/gL elicited IgG (f) recombinant gH/gL elicited IgG (g) or control IgG (h). Three technical replicates were run. i Viral DNA was quantified in splenic DNA extracts at necropsy. Each dot represents the average of three technical replicates for an individual mouse, the bar represents the median copy number per group, and the dashed line indicates the limit of detection. j Spleen weights at necropsy, each dot represents an individual mouse, and bar represents the median weight. Significant differences between all pairs of groups were assessed using Mann-Whitney tests in (i) and (j).