Development of antibody-modified chitosan nanoparticles for the targeted delivery of siRNA across the blood-brain barrier as a strategy for inhibiting HIV replication in astrocytes.
RNA interference (RNAi)-mediated gene silencing offers a novel treatment and prevention strategy for human immunodeficiency virus (HIV) infection. HIV was found to infect and replicate in human brain cells and can cause neuroinfections and neurological deterioration. We designed dual-antibody-modified chitosan/small interfering RNA (siRNA) nanoparticles to deliver siRNA across the blood-brain barrier (BBB) targeting HIV-infected brain astrocytes as a strategy for inhibiting HIV replication. We hypothesized that transferrin antibody and bradykinin B2 antibody could specifically bind to the transferrin receptor (TfR) and bradykinin B2 receptor (B2R), respectively, and deliver siRNA across the BBB into astrocytes as potential targeting ligands. In this study, chitosan nanoparticles (CS-NPs) were prepared by a complex coacervation method in the presence of siRNA, and antibody was chemically conjugated to the nanoparticles. The antibody-modified chitosan nanoparticles (Ab-CS-NPs) were spherical in shape, with an average particle size of 235.7 ± 10.2 nm and a zeta potential of 22.88 ± 1.78 mV. The therapeutic potential of the nanoparticles was evaluated based on their cellular uptake and gene silencing efficiency. Cellular accumulation and gene silencing efficiency of Ab-CS-NPs in astrocytes were significantly improved compared to non-modified CS-NPs and single-antibody-modified CS-NPs. These results suggest that the combination of anti-Tf antibody and anti-B2 antibody significantly increased the knockdown effect of siRNA-loaded nanoparticles. Thus, antibody-mediated dual-targeting nanoparticles are an efficient and promising delivery strategy for inhibiting HIV replication in astrocytes. Graphical abstract Graphic representation of dual-antibody-conjugated chitosan nanoparticles for the targeted delivery of siRNA across the blood-brain barrier (BBB) for inhibiting HIV replication in astrocytes. a Nanoparticle delivery to the BBB and penetration. b TfR-mediated transcytosis of nanoparticles across the epithelial cells. c B2R-mediated endocytosis of nanoparticles in astrocytes. d The molecular interactions between HIV-1 Tat protein and Cyclin T1 and Tip110 cellular proteins. e A schematic representation of chitosan nanoparticles with its components. RNAPII RNA polymerase II, TAR transactivation response RNA element, LTR long terminal repeat, Ab antibody, CS chitosan, TPP tripolyphosphate.
Laboratory for Drug Delivery and Biomaterials, College of Pharmacy, Rady Faculty of Health Sciences, University of Manitoba, 750 McDermot Ave, Winnipeg, MB, R3E 0T5, Canada.
Jijin
J
Gu
Laboratory for Drug Delivery and Biomaterials, College of Pharmacy, Rady Faculty of Health Sciences, University of Manitoba, 750 McDermot Ave, Winnipeg, MB, R3E 0T5, Canada.
Karam
K
Al-Bayati
Laboratory for Drug Delivery and Biomaterials, College of Pharmacy, Rady Faculty of Health Sciences, University of Manitoba, 750 McDermot Ave, Winnipeg, MB, R3E 0T5, Canada. emmanuel_ho@umanitoba.ca.
Emmanuel A
EA
Ho
D000906:Antibodies / Q000008:administration & dosage* / Q000737:chemistry; D000951:Antigens, Neoplasm / Q000235:genetics / Q000378:metabolism; D001253:Astrocytes / Q000187:drug effects / Q000821:virology; D001812:Blood-Brain Barrier / Q000378:metabolism; D002232:Carbocyanines / Q000008:administration & dosage / Q000737:chemistry; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000008:administration & dosage* / Q000737:chemistry; D056906:Cyclin T / Q000235:genetics / Q000378:metabolism; D005456:Fluorescent Dyes / Q000008:administration & dosage / Q000737:chemistry; D015497:HIV-1 / Q000187:drug effects / Q000502:physiology; D006801:Humans; D053758:Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000737:chemistry; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D043782:Receptor, Bradykinin B2 / Q000276:immunology*; D014168:Transferrin / Q000276:immunology*; D014779:Virus Replication / Q000187:drug effects
D000906:Antibodies; D000951:Antigens, Neoplasm; C503684:CCNT1 protein, human; D002232:Carbocyanines; D056906:Cyclin T; D005456:Fluorescent Dyes; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; D043782:Receptor, Bradykinin B2; C416530:SART3 protein, human; D014168:Transferrin; C089187:cyanine dye 3; D048271:Chitosan
Antibody; Brain delivery; Chitosan nanoparticles; Dual-targeting; siRNA