Antibody-Free\nGlycogen Nanoparticles Engage Human\nImmune T Cells for Intracellular Delivery of Small Drugs or mRNA

T cells\nplay a major role in immune defense against viral infections\nand diseases such as cancer. Accordingly, developing nanoparticle\n(NP) systems to effectively deliver therapeutics to T cells is of\ninterest. However, NP-mediated delivery of drugs to T cells is challenging\nbecause of the nonphagocytic nature of T cells. To engage T cells\nand induce cellular internalization, NPs are typically decorated with\nspecific receptor-targeting antibodies, often using laborious and\ncostly procedures. Herein, we report that natural glycogen NPs (i.e.,\nnanosugars) with different sizes (20–80 nm) and surface charges\n(neutral and positively charged) engage Jurkat T cells, undergo intracellular\ntrafficking, and release encapsulated drug without the use of receptor-targeting\nantibodies. Specifically, glycogen–resveratrol constructs are\nemployed to reactivate HIV-1 latently infected Jurkat T cells (J-Lat\nA2) and trigger proviral expression. Both neutral and positively charged\nglycogen NPs engage with J-Lat A2 cells. Large (84 ± 29 nm) and\npositively charged (23 ± 5 mV) NPs, denoted phytoglycogen-ethylenediamine\n(PG<sub>EDA</sub>) NPs, readily associate with the cell membrane and\nare internalized (60%) in J-Lat A2 cells but remain confined in the\nendocytic vesicles, with moderate reactivation of latent HIV-1 (4.7\n± 0.5%). Conversely, small (21 ± 5 nm) and positively charged\n(10 ± 6 mV) NPs, bovine glycogen-EDA (BG<sub>EDA</sub>) NPs,\nassociate slowly with T cells but show nearly 100% internalization\nand efficient endosomal escape properties, resulting in 1.5-fold higher\nreactivation of latent HIV-1 in T cells. PG<sub>EDA</sub> NPs and\nBG<sub>EDA</sub> NPs are also internalized by primary human T cells\n(>90% cell association) and enable the transfection of mRNA, with\nBG<sub>EDA</sub> NPs showing a 2-fold higher transfection than PG<sub>EDA</sub> NPs. This work highlights the potential of BG<sub>EDA</sub> NPs for the effective intracellular delivery of small-molecule drugs\nand mRNA in T cells.