El Kheir Wiam, Dumais Anaïs, Beaudoin Maude, Marcos Bernard, Virgilio Nick, Paquette Benoit, Faucheux Nathalie, Lauzon Marc-Antoine
Advanced Dynamic Cell Culture Systems Laboratory, Department of Chemical and Biotechnological Engineering, Faculty of Engineering, Université de Sherbrooke, Sherbrooke, QC, Canada.
Laboratory of Cell-Biomaterial Biohybrid Systems, Department of Chemical and Biotechnological Engineering, Faculty of Engineering, Université de Sherbrooke, Sherbrooke, QC, Canada.
Front Drug Deliv. 2023 Jul 24;3:1227776. doi: 10.3389/fddev.2023.1227776. eCollection 2023.
Extensive investigation has been undertaken regarding drug delivery systems for the management of glioblastoma multiforme (GBM). The infiltrative behavior of GBM cells within the brain tissue is primarily attributed to their heterogeneity, the movement of interstitial fluid (IFF), and the presence of chemokines. These factors contribute to the limited effectiveness of current conventional treatments. To address the dissemination of GBM cells, a proposed therapeutic approach involves utilizing a controlled release gradient of CXC-chemokine-ligand-12 (CXCL12). However, the impact of IFF on GBM cell migration within the brain underscores its critical importance as a significant parameter, which, surprisingly, has not been extensively studied in the context of localized drug delivery targeting the brain. Hydrogels are known for their inherent capacity to entrap various agents and exert precise control over their subsequent release. In the present investigation, we aimed to elucidate the release kinetics of CXCL12, whether in its free form or encapsulated within nanoparticles, from alginate-based hydrogels, both under static and dynamic conditions. To investigate the impact of convective forces mimicking the interstitial fluid flow (IFF) within the peritumoral environment of the brain, a three-dimensional model was developed. This model enabled the evaluation of CXCL12 release as a function of time and position, specifically accounting for the contribution of simulated IFF on the release behavior. We first demonstrated that the release kinetic profiles under static culture conditions were independent of the initial mass loading and the predominant phenomenon occurring was diffusion. Subsequently, we investigated the release of CXCL12, which was loaded into Alginate/Chitosan-Nanoparticles (Alg/Chit-NPs) and embedded within an alginate hydrogel matrix. Mathematical modeling results also indicated the presence of electrostatic interactions between alginate and CXCL12. The Alg/Chit-NPs effectively slowed down the initial burst release, leading to a reduction in the diffusion coefficient of CXCL12. To further study the release behavior, we developed a perfusion bioreactor with a unique culture chamber designed to recapitulate the peritumoral environment and varied the fluid flow rates at 0.5 µL/min, 3 µL/min, 6.5 µL/min, and 10 µL/min. As the flow rate increased, the cumulative amount of released CXCL12 also increased for all three initial mass loadings. Beyond 3 µL/min, convection became the dominant mechanism governing CXCL12 release, whereas below this threshold, diffusion played a more prominent role. The indirect perfusion flow had a crucial impact on CXCL12 release and distribution inside the hydrogel in and against its direction. This system highlights the importance of considering the IFF in brain targeting delivery system and will be used in the future to study GBM cell behaviors in response to CXCL12 gradient.
针对多形性胶质母细胞瘤(GBM)的治疗,人们对药物递送系统进行了广泛研究。GBM细胞在脑组织中的浸润行为主要归因于其异质性、间质液(IFF)的流动以及趋化因子的存在。这些因素导致了当前传统治疗方法效果有限。为了解决GBM细胞的扩散问题,一种提议的治疗方法是利用CXC趋化因子配体12(CXCL12)的控释梯度。然而,IFF对脑内GBM细胞迁移的影响凸显了其作为一个重要参数的关键重要性,令人惊讶的是,在针对脑的局部药物递送背景下,这方面尚未得到广泛研究。水凝胶以其固有能力捕获各种药物并精确控制其后续释放而闻名。在本研究中,我们旨在阐明CXCL12无论是以游离形式还是封装在纳米颗粒中,从基于藻酸盐的水凝胶在静态和动态条件下的释放动力学。为了研究模拟脑组织瘤周环境中间质液流动(IFF)的对流力的影响,我们开发了一个三维模型。该模型能够评估CXCL12的释放随时间和位置的变化,特别考虑了模拟IFF对释放行为的贡献。我们首先证明,静态培养条件下的释放动力学曲线与初始质量负载无关,主要发生的现象是扩散。随后,我们研究了负载到藻酸盐/壳聚糖纳米颗粒(Alg/Chit-NPs)中并嵌入藻酸盐水凝胶基质的CXCL12的释放。数学建模结果还表明藻酸盐和CXCL12之间存在静电相互作用。Alg/Chit-NPs有效地减缓了初始爆发释放,导致CXCL12的扩散系数降低。为了进一步研究释放行为,我们开发了一种灌注生物反应器,其独特的培养室旨在模拟瘤周环境,并将流体流速分别设置为0.5 μL/min、3 μL/min、6.5 μL/min和10 μL/min。随着流速增加,对于所有三种初始质量负载,释放的CXCL12的累积量也增加。超过3 μL/min,对流成为控制CXCL12释放的主要机制,而低于此阈值,扩散起更突出的作用。间接灌注流对水凝胶内CXCL12的释放和分布及其方向具有关键影响。该系统突出了在脑靶向递送系统中考虑IFF的重要性,并将在未来用于研究GBM细胞对CXCL12梯度的反应行为。