skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Development and Characterization of PLGA‐Based Multistage Delivery System for Enhanced Payload Delivery to Targeted Vascular Endothelium
Abstract Vascular‐targeted drug delivery remains an attractive platform for therapeutic and diagnostic interventions in human diseases. This work focuses on the development of a poly‐lactic‐co‐glycolic‐acid (PLGA)‐based multistage delivery system (MDS). MDS consists of two stages: a micron‐sized PLGA outer shell and encapsulated drug‐loaded PLGA nanoparticles. Nanoparticles with average diameters of 76, 119, and 193 nm are successfully encapsulated into 3–6 µm MDS. Sustained in vitro release of nanoparticles from MDS is observed for up to 7 days. Both MDS and nanoparticles arebiocompatible with human endothelial cells. Sialyl‐Lewis‐A (sLeA) is successfully immobilized on the MDS and nanoparticle surfaces to enable specific targeting of inflamed endothelium. Functionalized MDS demonstrates a 2.7‐fold improvement in endothelial binding compared to PLGA nanoparticles from human blood laminar flow. Overall, the presented results demonstrate successful development and characterization of MDS and suggest that MDS can serve as an effective drug carrier, which can enhance the margination of nanoparticles to the targeted vascular wall.  more » « less
Award ID(s):
1810995
PAR ID:
10452146
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Macromolecular Bioscience
Volume:
21
Issue:
3
ISSN:
1616-5187
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract Delivering cargo to the central nervous system (CNS) remains a pharmacological challenge. For infectious diseases such as HIV, the CNS acts as a latent reservoir that is inadequately managed by systemic antiretrovirals (ARTs). ARTs thus cannot eradicate HIV, and given CNS infection, patients experience neurological deficits collectively referred to as “neuroHIV”. Herein, the development of bioinspired ionic liquid‐coated nanoparticles (IL‐NPs) for in situ hitchhiking on red blood cells (RBCs) is reported, which enables 48% brain delivery of intracarotid arterial‐ infused cargo. Moreover, IL choline trans‐2‐hexenoate (CA2HA 1:2) demonstrates preferential accumulation in parenchymal microglia over endothelial cells post‐delivery. This study further demonstrates successful loading of abacavir (ABC), an ART that is challenging to encapsulate, into IL‐NPs, and verifies retention of antiviral efficacy in vitro. IL‐NPs are not cytotoxic to primary human peripheral blood mononuclear cells (PBMCs) and the CA2HA 1:2 coating itself confers notable anti‐viremic capacity. In addition, in vitro cell culture assays show markedly increased uptake of IL‐NPs into neural cells compared to bare PLGA nanoparticles. This work debuts bioinspired ionic liquids as promising nanoparticle coatings to assist CNS biodistribution and has the potential to revolutionize the delivery of cargos (i.e., drugs, viral vectors) through compartmental barriers such as the blood‐brain‐barrier (BBB). 
    more » « less
  2. Abstract Hematopoietic stem and progenitor cells (HSPCs) are desirable targets for gene therapy but are notoriously difficult to target and transfect. Existing viral vector‐based delivery methods are not effective in HSPCs due to their cytotoxicity, limited HSPC uptake and lack of target specificity (tropism). Poly(lactic‐co‐glycolic acid) (PLGA) nanoparticles (NPs) are attractive, nontoxic carriers that can encapsulate various cargo and enable its controlled release. To engineer PLGA NP tropism for HSPCs, megakaryocyte (Mk) membranes, which possess HSPC‐targeting moieties, were extracted and wrapped around PLGA NPs, producing MkNPs. In vitro, fluorophore‐labeled MkNPs are internalized by HSPCs within 24 h and were selectively taken up by HSPCs versus other physiologically related cell types. Using membranes from megakaryoblastic CHRF‐288 cells containing the same HSPC‐targeting moieties as Mks, CHRF‐wrapped NPs (CHNPs) loaded with small interfering RNA facilitated efficient RNA interference upon delivery to HSPCs in vitro. HSPC targeting was conserved in vivo, as poly(ethylene glycol)–PLGA NPs wrapped in CHRF membranes specifically targeted and were taken up by murine bone marrow HSPCs following intravenous administration. These findings suggest that MkNPs and CHNPs are effective and promising vehicles for targeted cargo delivery to HSPCs. 
    more » « less
  3. Vascular restenosis is a major complication in recanalized arteries. Nanoparticles (NPs) have shown great promise as delivery systems in advancing strategies to treat such vascular anomalies. By enabling precise targeting, NPs can overcome the challenges of low drug efficacy and off-target effects. Here we present a biomimetic in vitro platform comprised of 3D bioprinting, nanomaterials, and perfusion technologies, to study the use of NP targeting to address endothelial overgrowth. We bioprinted 3D vascular channels at high fidelity, using gelatin methacrylate as bioink, with artery-like stiffness. Human endothelial cells (ECs) were used to endothelialize the printed channels. GFP-labelled superparamagnetic iron oxide NPs (SPIONs), loaded with the Rapamune anti-proliferative drug, were perfused through the bifurcated artery model at physiological rate. Computational modeling predicted greatest level of alterations in wall shear stress in the conduit’s junction with the artery, identifying this region prone to restenosis. A neodymium disc magnet was embedded in the printed tissue to attract the therapeutic SPIONs to the region of high risk. In vitro dynamic culture was conducted for 2 wks. We assessed cell viability, proliferation, and function using AlamarBlue and immunohistochemistry. Results showed significant targeted effect of NP delivery in reducing EC overgrowth. This platform enables design of precise targeting of therapeutics to treat a variety of cardiovascular diseases at a high spatial and temporal control. 
    more » « less
  4. Abstract The brain vasculature maintains brain homeostasis by tightly regulating ionic, molecular, and cellular transport between the blood and the brain parenchyma. These blood–brain barrier (BBB) properties are impediments to brain drug delivery, and brain vascular dysfunction accompanies many neurological disorders. The molecular constituents of brain microvascular endothelial cells (BMECs) and pericytes, which share a basement membrane and comprise the microvessel structure, remain incompletely characterized, particularly in humans. To improve the molecular database of these cell types, we performed RNA sequencing on brain microvessel preparations isolated from snap-frozen human and mouse tissues by laser capture microdissection (LCM). The resulting transcriptome datasets from LCM microvessels were enriched in known brain endothelial and pericyte markers, and global comparison identified previously unknown microvessel-enriched genes. We used these datasets to identify mouse-human species differences in microvessel-associated gene expression that may have relevance to BBB regulation and drug delivery. Further, by comparison of human LCM microvessel data with existing human BMEC transcriptomic datasets, we identified novel putative markers of human brain pericytes. Together, these data improve the molecular definition of BMECs and brain pericytes, and are a resource for rational development of new brain-penetrant therapeutics and for advancing understanding of brain vascular function and dysfunction. 
    more » « less
  5. Abstract Nanocarrier and exosome encapsulation has been found to significantly increase the efficacy of targeted drug delivery while also minimizing unwanted side effects. However, the development of exosome-encapsulated drug nanocarriers is limited by low drug loading efficiencies and/or complex, time-consuming drug loading processes. Herein, we have developed an acoustofluidic device that simultaneously performs both drug loading and exosome encapsulation. By synergistically leveraging the acoustic radiation force, acoustic microstreaming, and shear stresses in a rotating droplet, the concentration, and fusion of exosomes, drugs, and porous silica nanoparticles is achieved. The final product consists of drug-loaded silica nanocarriers that are encased within an exosomal membrane. The drug loading efficiency is significantly improved, with nearly 30% of the free drug (e.g., doxorubicin) molecules loaded into the nanocarriers. Furthermore, this acoustofluidic drug loading system circumvents the need for complex chemical modification, allowing drug loading and encapsulation to be completed within a matter of minutes. These exosome-encapsulated nanocarriers exhibit excellent efficiency in intracellular transport and are capable of significantly inhibiting tumor cell proliferation. By utilizing physical forces to rapidly generate hybrid nanocarriers, this acoustofluidic drug loading platform wields the potential to significantly impact innovation in both drug delivery research and applications. 
    more » « less