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Cryopreservation of microglia enables single-cell RNA sequencing with minimal effects on disease-related gene expression patterns.

ABSTRACT: 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.

SUBMITTER: Morsey B

PROVIDER: S-EPMC8044433 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Cryopreservation of microglia enables single-cell RNA sequencing with minimal effects on disease-related gene expression patterns.

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