Morsey Brenda, Niu Meng, Dyavar Shetty Ravi, Fletcher Courtney V, Lamberty Benjamin G, Emanuel Katy, Fangmeier Anna, Fox Howard S
Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE 68198, USA.
Department of Genetics, Cell Biology and Anatomy; and Bioinformatics and Systems Biology Core, University of Nebraska Medical Center, Omaha, NE 68198, USA.
iScience. 2021 Mar 25;24(4):102357. doi: 10.1016/j.isci.2021.102357. eCollection 2021 Apr 23.
Microglia play a key role in brain development, normal homeostasis, and neurodegenerative disorders. Single-cell technologies have led to important findings about microglia, with many animal model studies using single-cell RNA sequencing (scRNA-seq), whereas most human specimen studies using archived frozen brains for single-nucleus RNA sequencing (snRNA-seq). However, microglia compose a small proportion of the total brain tissue; snRNAseq depletes expression of microglia activation genes that characterize many diseases. Here we examine the use of purified, cryopreserved microglia for scRNA-seq. Comparison of scRNA-seq on paired fresh and cryopreserved microglia from rhesus monkeys revealed a high level of correlation of gene expression between the two conditions. Disease-related genes were relatively unaffected, but an increase in immediate-early gene expression was present in cryopreserved cells. Regardless, changes in immediate-early gene expression are still detectable. Cryopreservation of microglia is a suitable procedure for prospectively archiving samples.
小胶质细胞在大脑发育、正常稳态及神经退行性疾病中发挥关键作用。单细胞技术已带来有关小胶质细胞的重要发现，许多动物模型研究采用单细胞RNA测序（scRNA-seq），而大多数人类标本研究则使用存档的冷冻大脑进行单核RNA测序（snRNA-seq）。然而，小胶质细胞在整个脑组织中所占比例较小；snRNAseq会使表征许多疾病的小胶质细胞激活基因的表达缺失。在此，我们研究了使用纯化的、冷冻保存的小胶质细胞进行scRNA-seq的情况。对来自恒河猴的配对新鲜和冷冻保存的小胶质细胞进行scRNA-seq比较，结果显示两种条件下基因表达的相关性很高。疾病相关基因相对未受影响，但冷冻保存的细胞中即刻早期基因表达有所增加。尽管如此，即刻早期基因表达的变化仍然可以检测到。小胶质细胞的冷冻保存是一种适合前瞻性存档样本的方法。
