RNA Sequencing of dendritic cells treated with glycan-costumed virus-like particles

We engineered a glycan-costumed virus-like particle (VLP) vaccine that delivers programmable peptide antigens to induce tumor-specific cellular immunity in vivo. VLPs encapsulating TLR7 agonists were decorated with a synthetic mannose-derived ligand (VLP-Man-OvaI/II) that selectively engages the lectin DC-SIGN. Lectin-TLR7 dual engagement induced robust DC activation and type 1 cellular immunity, whereas VLPs lacking this key DC-SIGN ligand (VLP-PE-OvaI/II) failed to promote DC-mediated cellular responses. We performed bulk RNA-seq experiments on moDCs treated with VLP-Man-OvaI/II and VLP-PE-OvaI/II or unstimulated control moDCs. A total of 486 genes were differentially expressed after treatment with VLP-Man-OvaI/II vs. VLP-PE-OvaI/II (log2FC >1.5 and p<0.05). The significantly upregulated genes included CXCL1, CXCL5, ISG15, IL6, CCL4, ISG20, and SOCS3, all of which are implicated in the TLR7 downstream signaling pathway, suggesting a higher extent of TLR7 activation with the VLP-Man-OvaI/II. Gene set enrichment analysis (GSEA) between VLP-Man-OvaI/II- and VLP-PE-OvaI/II-treated moDCs revealed that hallmark DC activation pathways were also upregulated in VLP-Man-OvaI/II-treated DCs, including pathways related to IFN-a, IFN-g, and TNF-a signaling via nuclear factor-κB (NF-kB). These data give insight into how lectin binding with glycan-costumed VLPs can be employed to reprogram immunity.