Microglia are critically involved in complex neurological disorders with a strong genetic component, such as Alzheimer’s disease, Parkinson’s disease and frontotemporal dementia. Although mouse microglia can recapitulate aspects of human microglia physiology, they do not fully capture the human genetic aspects of disease and do not reproduce all human cell states. Primary cultures of human microglia or microglia derived from human induced pluripotent stem cells (PSCs) are difficult to maintain in brain-relevant cell states in vitro. Here we describe MIGRATE (microglia in vitro generation refined for advanced transplantation experiments, which provides a combined in vitro differentiation and in vivo xenotransplantation protocol to study human microglia in the context of the mouse brain. This article details an accurate, step-by-step workflow that includes in vitro microglia differentiation from human PSCs, transplantation into the mouse brain and quantitative analysis of engraftment. Compared to current differentiation and xenotransplantation protocols, we present an optimized, faster and more efficient approach that yields up to 80% chimerism. To quantitatively assess engraftment efficiency by flow cytometry, access to specialized flow cytometry is required. Alternatively, the percentage of chimerism can be estimated by standard immunohistochemical analysis. The MIGRATE protocol takes ~40 d to complete, from culturing PSCs to engraftment efficiency assessment.

小胶质细胞与具有强烈遗传成分的复杂神经系统疾病密切相关，例如阿尔茨海默病、帕金森病和额颞叶痴呆。尽管小鼠小胶质细胞可以概括人类小胶质细胞生理学的各个方面，但它们并不能完全捕捉到疾病的人类遗传方面，也不能再现所有人类细胞状态。人小胶质细胞或源自人诱导多能干细胞 (PSC) 的小胶质细胞的原代培养物难以在体外维持与脑相关的细胞状态。在这里，我们描述了 MIGRATE（为高级移植实验而改进的小胶质细胞体外生成，它提供了一种结合体外分化和体内异种移植方案来研究小鼠大脑背景下的人类小胶质细胞。这篇文章详细介绍了一个准确的、一步一步的工作流程，包括从人 PSC 中体外分化小胶质细胞、移植到小鼠大脑中以及对移植物进行定量分析。与当前的分化和异种移植方案相比，我们提出了一种优化、更快、更有效的方法，可产生高达 80% 的嵌合体。为了通过流式细胞仪定量评估植入效率，需要使用专门的流式细胞仪。或者，嵌合体的百分比可以通过标准免疫组织化学分析来估计。从培养 PSC 到植入效率评估，MIGRATE 协议需要约 40 天才能完成。与当前的分化和异种移植方案相比，我们提出了一种优化、更快、更有效的方法，可产生高达 80% 的嵌合体。为了通过流式细胞仪定量评估植入效率，需要使用专门的流式细胞仪。或者，嵌合体的百分比可以通过标准免疫组织化学分析来估计。从培养 PSC 到植入效率评估，MIGRATE 协议需要约 40 天才能完成。与当前的分化和异种移植方案相比，我们提出了一种优化、更快、更有效的方法，可产生高达 80% 的嵌合体。为了通过流式细胞仪定量评估植入效率，需要使用专门的流式细胞仪。或者，嵌合体的百分比可以通过标准免疫组织化学分析来估计。从培养 PSC 到植入效率评估，MIGRATE 协议需要约 40 天才能完成。