Montaser, A. | bioRxiv Science

bioRxiv2026

Tunable Rigid Spikes on Virus-Like Porous Silica Enable Mechanistically Controlled Nanovaccine Platforms

Virus-like particles represent an emerging and promising vaccine platform. However, these particles are inherently mechanically soft and have limited control over particle surface architecture, thereby constraining their immunological control. Herein, we report the rational design of bioinspired virus-like porous silica (VLPSi) nanoparticles (NPs) with tunable and mechanically rigid spike architectures that function dually as antigen delivery carriers and immune adjuvants. Using ovalbumin (OVA) as a model antigen, we systematically elucidate the spiky structure-function relationship in antigen delivery and immune response. VLPSi NPs exhibit good biocompatibility, sustained antigen release, and markedly enhanced cellular uptake and endosomal escape compared with soft spike and spherical counterparts. Mechanistic investigations combining molecular dynamics simulations and proteomic analyses reveal that rigid spike architectures reduce the energetic barrier for cellular internalization and concurrently activate dual pathways involving endosomal Toll like receptors and calcium signaling. Consequently, VLPSi with long spikes elicit significantly enhanced humoral and cellular immune responses, outperforming the particles with shorter spikes, spherical shape as well as clinically used alum adjuvant. To demonstrate translational potential, bioinspired antibacterial vaccines were produced by loading Staphylococcus aureus surface protein rEsxB. The VLPSi-based vaccine elicited robust protective immunity to achieve complete (100%) survival following lethal challenge without detectable adverse effects, whereas traditional Alum-adjuvanted formulation conferred only minimal protection, with a survival rate of 10%. Collectively, this work establishes VLPSi with tunable spikes as a mechanistically controlled platform for next generation vaccines. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=145 SRC="FIGDIR/small/720861v1_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@1f6c13eorg.highwire.dtl.DTLVardef@1090d07org.highwire.dtl.DTLVardef@1364926org.highwire.dtl.DTLVardef@fc68ab_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2025

Mechanism of biomimetic virus-like nanoparticles in triggering immune response elucidated by proteomics

The use of biomimetic nanoparticles (NPs) with virus-like morphology have recently attracted research interest as novel delivery platforms and immune adjuvants. However, the exact interactions between the nanoparticles and immune cells as well as the mechanism involved are not known in detail. This motivated us to develop virus-like mesoporous silica nanoparticles (VLP) to characterize their physicochemical properties, and to determine the immune pathways induced by the particles in mouse macrophages. The results showed inclusion of spikes mimicking virion structures on the surface increased cellular uptake and enhanced immune response as compared to spherical NPs. Proteomic analysis revealed that the RIG-I-like receptor signaling pathway, Chemokine signaling pathway, MAPK signaling pathway, NF-{kappa}B signaling pathway, Toll-like receptor signaling pathway, B cell receptor signaling pathway and Th1 and Th2 cell differentiation pathways were involved in regulating the immune response when macrophages interacted with VLP. When the spikes increased from 5 to 30 nm, the expression levels of immune-related proteins including TRAF6 and PIAS4 proteins enhanced. This study revealed the interaction pathways and key proteins in the activation of immune response with VLP, which may provide insights to develop novel immunotherapy for enhanced efficacy. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=177 SRC="FIGDIR/small/640536v3_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@395d6forg.highwire.dtl.DTLVardef@25238dorg.highwire.dtl.DTLVardef@41001borg.highwire.dtl.DTLVardef@16dfe2e_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗