Mannosylation of Lipid Nanoparticles (LNP) can potentially enhance uptake by Antigen Presenting Cells, which are highly abundant in dermal tissues, to improve the potency of Self Amplifying mRNA (SAM) vaccines in comparison to the established unmodified LNP delivery system. In the current studies, we evaluated mannosylated LNP (MLNP), which were obtained by incorporation of a stable Mannose-cholesterol amine conjugate, for the delivery of an influenza (hemagglutinin) encoded SAM vaccine in mice, by both intramuscular and intradermal routes of administration. SAM MLNP exhibited in vitro enhanced uptake in comparison to unglycosylated LNP from bone marrow-derived dendritic cells, and in vivo more rapid onset of the antibody response, independent of the route. The increased binding antibody levels also translated into higher functional hemagglutinin inhibition titers, particularly following intradermal administration. T cell assay on splenocytes from immunized mice also showed an increase in antigen specific CD8+ T responses, following intradermal administration of MLNP SAM vaccines. Induction of enhanced antigen specific CD4+ T cells, correlating with higher IgG2a antibody responses, was also observed. Hence, the present work illustrates the benefit of mannosylation of LNPs to achieve a faster immune response with SAM vaccines and these observations could contribute to the development of novel skin delivery systems for SAM vaccines.

中文翻译：

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LNP的甘露糖基化可提高自我扩增RNA（SAM）疫苗的效力。

与已建立的未经修饰的LNP递送系统相比，脂质纳米颗粒（LNP）的甘露糖基化可以潜在地增强抗原提呈细胞的吸收，该抗原提呈细胞在皮肤组织中高度丰富，从而提高了自我扩增mRNA（SAM）疫苗的效力。在当前的研究中，我们评估了通过掺入稳定的甘露糖-胆固醇胺结合物而获得的甘露糖基化的LNP（MLNP），通过肌肉内和皮内给药途径在小鼠中递送流感（血凝素）编码的SAM疫苗。与来自骨髓的树突状细胞的未糖基化的LNP相比，SAM MLNP的体外吸收增强，并且与途径无关，体内抗体应答的起效更快。结合抗体水平的升高还转化为更高的功能性血凝素抑制效价，尤其是在皮内给药后。皮内注射MLNP SAM疫苗后，对免疫小鼠脾细胞进行的T细胞分析也显示出抗原特异性CD8 + T反应的增加。还观察到与更高的IgG2a抗体反应相关的增强的抗原特异性CD4 + T细胞的诱导。因此，本工作说明了LNP的甘露糖基化对于用SAM疫苗实现更快的免疫反应的好处，这些观察结果可能有助于开发用于SAM疫苗的新型皮肤递送系统。皮内注射MLNP SAM疫苗后，对免疫小鼠脾细胞进行的T细胞分析也显示出抗原特异性CD8 + T反应的增加。还观察到与更高的IgG2a抗体反应相关的增强的抗原特异性CD4 + T细胞的诱导。因此，本工作说明了LNP的甘露糖基化对用SAM疫苗实现更快的免疫反应的好处，这些观察结果可能有助于开发用于SAM疫苗的新型皮肤递送系统。皮内注射MLNP SAM疫苗后，对免疫小鼠脾细胞进行的T细胞分析也显示出抗原特异性CD8 + T反应的增加。还观察到与更高的IgG2a抗体反应相关的增强的抗原特异性CD4 + T细胞的诱导。因此，本工作说明了LNP的甘露糖基化对用SAM疫苗实现更快的免疫反应的好处，这些观察结果可能有助于开发用于SAM疫苗的新型皮肤递送系统。