Nash Victoria A, Cortes-Troncoso Juan F, Chua Phoebe E, Spiller Kara L
School of Biomedical Engineering, Sciences and Health Systems, Drexel University, Philadelphia, PA 19104, United States of America.
School of Biomedical Engineering, Sciences and Health Systems, Drexel University, Philadelphia, PA 19104, United States of America.
J Control Release. 2025 Aug 10;384:113943. doi: 10.1016/j.jconrel.2025.113943. Epub 2025 Jun 9.
Immunomodulatory cytokines like interleukin-4 (IL-4) can modulate host immune cell behavior to improve tissue integration, but versatile strategies for modifying complex biomaterials to control the release of such cytokines are limited. Bioconjugation strategies using biotin-avidin interactions offer a promising approach since biotin can be conjugated to proteins, biomaterials, and even cells, without compromising their function. Although it is known that conjugation of biotin to large biomolecules reduces its binding affinity for avidin and avidin variants, the potential to control the release of biotinylated molecules by leveraging these changes in affinity interactions has not been thoroughly investigated. Moreover, the effects of biotin and avidin variants on innate immunity are poorly understood. Therefore, the goals of this study were to determine if biotin-avidin interactions could be manipulated to control the release of IL-4 from biomaterials and to investigate the subsequent effects on primary human macrophage phenotype. First, we characterized the effects of soluble biotin, avidin, and avidin variants, streptavidin and CaptAvidin, on the phenotype of primary human macrophages from 8 different donors using RNA sequencing, finding that CaptAvidin influenced macrophage gene expression much more than the other variants. Then, after evaluating how bioconjugation parameters influenced biotin density and avidin variant binding to porous gelatin scaffolds, we found that biotin-avidin affinity interactions sustained the release of biotinylated IL-4 (bIL-4) from biotinylated and desthiobiotinylated scaffolds bound with either avidin or streptavidin for up to 14 days in vitro. Finally, we measured the response of primary human macrophages from 5 donors to the bIL-4-releasing scaffolds, finding an increase in reparative macrophage phenotype gene expression when bIL-4 was released via biotin-streptavidin interactions compared to scaffolds that relied solely on desorption-based release. These results highlight how biotin-streptavidin interactions can be leveraged for controlled release to achieve an immunomodulatory drug delivery system.
像白细胞介素-4（IL-4）这样的免疫调节细胞因子可以调节宿主免疫细胞行为以改善组织整合，但用于修饰复杂生物材料以控制此类细胞因子释放的通用策略有限。利用生物素-抗生物素蛋白相互作用的生物共轭策略提供了一种有前景的方法，因为生物素可以与蛋白质、生物材料甚至细胞共轭，而不损害它们的功能。尽管已知生物素与大分子共轭会降低其与抗生物素蛋白及抗生物素蛋白变体的结合亲和力，但利用这些亲和力相互作用的变化来控制生物素化分子释放的潜力尚未得到充分研究。此外，生物素和抗生物素蛋白变体对先天免疫的影响了解甚少。因此，本研究的目标是确定生物素-抗生物素蛋白相互作用是否可以被操纵以控制IL-4从生物材料中的释放，并研究其对原代人巨噬细胞表型的后续影响。首先，我们使用RNA测序表征了可溶性生物素、抗生物素蛋白和抗生物素蛋白变体、链霉抗生物素蛋白和CaptAvidin对来自8个不同供体的原代人巨噬细胞表型的影响，发现CaptAvidin对巨噬细胞基因表达的影响比其他变体大得多。然后，在评估生物共轭参数如何影响生物素密度以及抗生物素蛋白变体与多孔明胶支架的结合后，我们发现生物素-抗生物素蛋白亲和力相互作用在体外可使与抗生物素蛋白或链霉抗生物素蛋白结合的生物素化和脱硫生物素化支架中生物素化IL-4（bIL-4）持续释放长达14天。最后，我们测量了来自5个供体的原代人巨噬细胞对释放bIL-4的支架的反应，发现与仅依赖基于解吸释放的支架相比，当bIL-4通过生物素-链霉抗生物素蛋白相互作用释放时，修复性巨噬细胞表型基因表达增加。这些结果突出了生物素-链霉抗生物素蛋白相互作用如何可用于控释以实现免疫调节药物递送系统。
