Abstract：
Plasma cells (PCs) in bone marrow (BM) play an important role in both protective and pathogenic humoral immune responses, e.g. in various malignant and non-malignant diseases such as multiple myeloma, primary and secondary immunodeficiencies and autoimmune diseases. Dedicated microenvironmental niches in the BM provide PCs with biomechanical and soluble factors that support their long-term survival. There is a high need for appropriate and robust model systems to better understand PCs biology, to develop new therapeutic strategies for PCs-related diseases and perform targeted preclinical studies with high predictive value. Most preclinical data have been derived fromin vivostudies in mice, asin vitrostudies of human PCs are limited due to restricted survival and functionality in conventional 2D cultures that do not reflect the unique niche architecture of the BM. We have developed a microphysiological, dynamic 3D BM culture system (BM-MPS) based on human primary tissue (femoral biopsies), mechanically supported by a hydrogel scaffold casing. While a bioinert agarose casing did not support PCs survival, a photo-crosslinked collagen-hyaluronic acid (Col-HA) hydrogel preserved the native BM niche architecture and allowed PCs survivalin vitrofor up to 2 weeks. Further, the Col-HA hydrogel was permissive to lymphocyte migration into the microphysiological system´s circulation. Long-term PCs survival was related to the stable presence in the culture of soluble factors, as APRIL, BAFF, and IL-6. Increasing immunoglobulins concentrations in the medium confirm their functionality over culture time. To the best of our knowledge, this study is the first report of successful long-term maintenance of primary-derived non-malignant PCsin vitro. Our innovative model system is suitable for in-depthin vitrostudies of human PCs regulation and exploration of targeted therapeutic approaches such as CAR-T cell therapy or biologics.
摘要：
骨髓(BM)中的浆细胞(PC)在保护性和致病性体液免疫应答中起重要作用。例如，在各种恶性和非恶性疾病，如多发性骨髓瘤（MM），原发性和继发性免疫缺陷和自身免疫性疾病。BM中专用的微环境壁龛为PC提供了支持其长期生存的生物力学和可溶性因子。非常需要适当和强大的模型系统来更好地了解PC生物学，为PC相关疾病开发新的治疗策略，并进行具有高预测价值的靶向临床前研究。大多数临床前数据来自小鼠体内研究，因为人PC的体外研究是有限的，因为在传统的2D培养物中有限的存活和功能，不反映BM的独特生态位结构。我们开发了一种微生理学，基于人体原代组织（股骨活检）的动态3DBM培养系统（BM-MPS），由水凝胶支架外壳机械支撑。虽然生物惰性琼脂糖外壳不支持PC存活，光交联的胶原蛋白-透明质酸（Col-HA）水凝胶保留了天然的BM生态位结构，并允许PC在体外存活长达2周。Further,Col-HA水凝胶允许淋巴细胞迁移到微生理系统的循环中。PCs的长期存活与可溶性因子在培养物中的稳定存在有关，作为4月，BAFF,IL-6培养基中免疫球蛋白浓度的增加证实了它们随培养时间的功能。据我们所知,这项研究是首次报道在体外成功长期维持原发性非恶性PC。我们的创新模型系统适用于对人类PC调节的深入体外研究，并探索靶向治疗方法，如CAR-T细胞疗法或生物制剂。
