Ex vivo isolated human vessel perfusion system for the design and assessment of nanomedicines targeted to the endothelium

Abstract

Endothelial cells play a central role in the process of inflammation. Their biologic relevance, as well as their accessibility to IV injected therapeutics, make them a strong candidate for treatment with molecularly-targeted nanomedicines. Typically, the properties of targeted nanomedicines are first optimized in vitro in cell culture and then in vivo in rodent models. While cultured cells are readily available for study, results obtained from isolated cells can lack relevance to more complex in vivo environments. On the other hand, the quantitative assays needed to determine the impact of nanoparticle design on targeting efficacy are difficult to perform in animal models. Moreover, results from animal models often translate poorly to human systems. To address the need for an improved testing platform, we developed an isolated vessel perfusion system to enable dynamic and quantitative study of vascular-targeted nanomedicines in readily obtainable human vessels isolated from umbilical cords or placenta. We show that this platform technology enables the evaluation of parameters that are critical to targeting efficacy (including flow rate, selection of targeting molecule, and temperature). Furthermore, biologic replicates can be easily produced by evaluating multiple vessel segments from the same human donor in independent, modular chambers. The chambers can also be adapted to house vessels of a variety of sizes, allowing for the subsequent study of vessel segments in vivo following transplantation into immunodeficient mice. We believe this perfusion system can help to address long-standing issues in endothelial targeted nanomedicines and thereby enable more effective clinical translation. K E Y W O R D S clinical translation, drug delivery systems, endothelial cell targeting, ex vivo perfusion, molecularly targeted therapies, nanoparticle accumulation, nanotechnology

Wanted: An endothelial cell targeting atlas for nanotherapeutic delivery in allograft organs

“…The modular design of polymeric nanoparticles (NPs) makes them particularly well‐suited to the task of drug delivery during NMP 5–8 . To achieve carrier specificity, the surface, size, and charge of polymeric NPs can be adjusted to minimize cellular interaction with off‐target cells.…”

“…To achieve carrier specificity, the surface, size, and charge of polymeric NPs can be adjusted to minimize cellular interaction with off‐target cells. A variety of targeting ligands (e.g., antibodies, peptides) can be attached to the NP surface to enable retention by the EC subtype of interest 7–10 . Durability of drug effect can be achieved by manipulating the polymer composition and molecular weight to slow the rate of particle degradation; prolonged drug release spanning weeks to months has been routinely demonstrated 11 .…”

“…The modular design of polymeric nanoparticles (NPs) makes them particularly well-suited to the task of drug delivery during NMP. [5][6][7][8] To achieve carrier specificity, the surface, size, and charge of polymeric NPs can be adjusted to minimize cellular interaction with off-target cells. A variety of targeting ligands (e.g., antibodies, peptides) can be attached to the NP surface to enable retention by the EC subtype of interest.…”

Regulation mechanisms of endocrine disruptors on vasodilation and vasoconstriction: Insights from ex vivo models

“…Both systems allow to achievement of a physiological blood vessel environment. The main advantage of the perfusion system is that the vessel segments are maintained as 3D structures with an intact native endothelial lining (if isolated and mounted correctly), allowing quantification of nanoparticles accumulation and cellular response (Lysyy et al, 2020). Regarding the organ bath, the main advantage is allowing to isolate pharmacological responses, drug testing, and easy repeatable (Jespersen et al, 2015).…”

Investigation of Wall Shear Stress in Cardiovascular Research and in Clinical Practice—From Bench to Bedside

“…To date, hemodynamics research has most frequently been carried out and has elucidated atherogenic hemodynamics ex vivo. Although vessels from animals have been used in most ex vivo models, there is an increasing number of studies which have successfully utilized human vessels, such as the human saphenous vein [ 73 , 74 , 75 ] or human umbilical vein [ 76 , 77 ], to overcome interspecies differences.…”