Baako Ann K, Vijayakumar Ragavi, Medina-Cano Daniel, Wang Zhaoquan, Romero-Pichardo Jesús, Fadojutimi Kelvin, Do Stephanie C, Lin Yuan, Islam Mohammed, Dixit Sanjana, Trzeciak Alissa J, Perry Justin S A, Vierbuchen Thomas
Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
bioRxiv. 2025 May 13:2025.05.01.651743. doi: 10.1101/2025.05.01.651743.
Tissue-resident macrophages (TRMs) are innate immune cells that participate in tissue development, homeostasis, and immune surveillance. Extensive efforts have been made to recapitulate TRM development from pluripotent stem cells (PSCs) to study molecular and cellular mechanisms of TRM development and to create cellular models of disease. However, available PSC models of mouse TRM development exhibit low overall efficiencies of TRM generation, produce heterogeneous off-target populations, and rely upon undefined media components, thus limiting their reproducibility, scalability, and widespread application as an experimental platform for TRM biology. To address these important limitations, we developed an efficient and reproducible protocol to faithfully recapitulate the stepwise differentiation of mouse PSCs (epiblast stem cells) into unspecialized, proliferative TRMs through the pro-definitive hematopoietic program under defined conditions. These immature TRMs can stably integrate into developing mouse neural organoids and acquire features of microglia. In addition, PSC-derived immature TRMs can stably engraft into the lung niche and adopt alveolar macrophage characteristics. This new platform for modeling mouse TRM development represents a powerful experimental model system for studying TRM function and dysfunction in development and disease.
组织驻留巨噬细胞（TRM）是参与组织发育、稳态和免疫监视的固有免疫细胞。人们已经付出了巨大努力来重现从多能干细胞（PSC）发育而来的TRM，以研究TRM发育的分子和细胞机制，并创建疾病细胞模型。然而，现有的小鼠TRM发育的PSC模型显示出TRM生成的总体效率较低，产生异质性的脱靶群体，并且依赖于成分不明确的培养基，因此限制了它们作为TRM生物学实验平台的可重复性、可扩展性和广泛应用。为了解决这些重要限制，我们开发了一种高效且可重复的方案，在明确的条件下，通过原定型造血程序，如实地重现小鼠PSC（上胚层干细胞）向未分化、增殖性TRM的逐步分化。这些未成熟的TRM可以稳定地整合到发育中的小鼠神经类器官中，并获得小胶质细胞的特征。此外，PSC衍生的未成熟TRM可以稳定地植入肺生态位并呈现肺泡巨噬细胞的特征。这个用于模拟小鼠TRM发育的新平台代表了一个强大的实验模型系统，用于研究TRM在发育和疾病中的功能及功能障碍。
