Fig. 4.

BG505.SOSIP.664 (SOSIP) protein and its display on NVP surface after loading. a) Genetic modifications from Env gp160 resulted in SOSIP, having truncation at residue 664, added glycan (indicated by *; T332N) and a disulfide bond, and other point mutations. MPER: membrane proximal region, TM: transmembrane domain, CT: cytosolic tail. b) Loading of SOSIP into NVP confirmed by non-reducing PAGE, followed by silver staining. c) Blue native PAGE showing intact SOSIP trimer before or after physical disruption as well as after loading in NVP using an optimized formulation condition. d-e) To examine SOSIP display on NVP, human anti-SOSIP antibodies, b6 and PGV04, were incubated with SOSIP-NVP and PE-labeled anti-human IgG antibody, followed by quantification of antibody binding by d) plate-based fluorescence measurement and e) individual nanoparticle-based flow cytometry. Data are presented as mean ± SEM. *p < 0.05, ***p < 0.001, analyzed by one-way ANOVA, followed by Tukey's HSD multiple comparison post hoc test. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)