ABSTRACT
Activating humoral and cellular immunity in lymph nodes (LNs) of nanoparticle-based vaccines is critical to controlling tumors. However, how the physical properties of nanovaccine carriers orchestrate antigen capture, lymphatic delivery, antigen presentation and immune response in LNs is largely unclear. Here, we manufactured gold nanoparticles (AuNPs) with the same size but different shapes (cages, rods, and stars), and loaded tumor antigen as nanovaccines to explore their disparate characters on above four areas. Results revealed that star-shaped AuNPs captured and retained more repetitive antigen epitopes. On lymphatic delivery, both rods and star-shaped nanovaccines mainly drain into the LN follicles region while cage-shaped showed stronger paracortex retention. A surprising finding is that the star-shaped nanovaccines elicited potent humoral immunity, which is mediated by CD4+ T helper cell and follicle B cell cooperation significantly preventing tumor growth in the prophylactic study. Interestingly, cage-shaped nanovaccines preferentially presented peptide-MHC I complexes to evoke robust CD8+ T cell immunity and showed the strongest therapeutic efficacy when combined with the PD-1 checkpoint inhibitor in established tumor study. These results highlight the importance of nanoparticle shape on antigen delivery and presentation for immune response in LNs, and our findings support the notion that different design strategies are required for prophylactic and therapeutic vaccines.
ABSTRACT
Objective To prepare rabbit antibody against mouse AD-004 by AD-004 expressed in the prokaryotic expression system and to identify its distribution in the testis and adrenal. Methods The full-length cDNA of mouse AD-004 was cloned into PET28 plasmid, and the protein was induced in E. coli BL21 bacteria by adding IPTC and then purified by Ni2+ -NTA column. The purified protein was used as an immunogen to prepare polyclonal antibody ( pAb) of AD-004. The specificity of the antibody was detected by Western blotting. Immunohistochemical staining was performed in the mouse adrenal and testis via pAb of AD-004. Results Hisfused AD-004 was expressed efficiently in the prokaryotic system. Western blot analysis showed that the polyclonal antibody was duly bound to purified AD-004 with high specificity and sensitivity. AD-004 could be abundantly identified in the adrenal medulla and mainly expressed in the Leydig cells of testis. Conclusion The mouse protein of AD-004 is obtained from the prokaryotic expression system. The rabbit anti-AD-004 antibody has been prepared successfully. AD-004 protein is mainly localized in the interstitium of testis, suggesting that AD-004 may play a role in the synthesis of sex-steroid hormone.