从 FFPE 切片和组织学定向亚区中进行无提取的全转录组基因表达分析。
Extraction-free whole transcriptome gene expression analysis of FFPE sections and histology-directed subareas of tissue.
机构信息
BioSpyder Technologies, Inc., Carlsbad, California, United States of America.
出版信息
PLoS One. 2019 Feb 22;14(2):e0212031. doi: 10.1371/journal.pone.0212031. eCollection 2019.
We describe the use of a ligation-based targeted whole transcriptome expression profiling assay, TempO-Seq, to profile formalin-fixed paraffin-embedded (FFPE) tissue, including H&E stained FFPE tissue, by directly lysing tissue scraped from slides without extracting RNA or converting the RNA to cDNA. The correlation of measured gene expression changes in unfixed and fixed samples using blocks prepared from a pellet of a single cell type was R2 = 0.97, demonstrating that no significant artifacts were introduced by fixation. Fixed and fresh samples prepared in an equivalent manner produced comparable sequencing depth results (+/- 20%), with similar %CV (11.5 and 12.7%, respectively), indicating no significant loss of measurable RNA due to fixation. The sensitivity of the TempO-Seq assay was the same whether the tissue section was fixed or not. The assay performance was equivalent for human, mouse, or rat whole transcriptome. The results from 10 mm2 and 2 mm2 areas of tissue obtained from 5 μm thick sections were equivalent, thus demonstrating high sensitivity and ability to profile focal areas of histology within a section. Replicate reproducibility of separate areas of tissue ranged from R2 = 0.83 (lung) to 0.96 (liver) depending on the tissue type, with an average correlation of R2 = 0.90 across nine tissue types. The average %CVs were 16.8% for genes expressed at greater than 200 counts, and 20.3% for genes greater than 50 counts. Tissue specific differences in gene expression were identified and agreed with the literature. There was negligible impact on assay performance using FFPE tissues that had been archived for up to 30 years. Similarly, there was negligible impact of H&E staining, facilitating accurate visualization for scraping and assay of small focal areas of specific histology within a section.
我们描述了一种基于连接的靶向全转录组表达谱分析方法,TempO-Seq,用于对福尔马林固定石蜡包埋(FFPE)组织进行分析,包括直接从载玻片上刮取组织进行分析,而无需提取 RNA 或将 RNA 转化为 cDNA。使用单细胞类型的沉淀制备的块进行的未固定和固定样品的测量基因表达变化之间的相关性为 R2 = 0.97,表明固定过程没有引入明显的假象。以相同的方式制备的固定和新鲜样品产生了相似的测序深度结果(+/- 20%),具有相似的 %CV(分别为 11.5%和 12.7%),表明固定过程中没有明显的可测量 RNA 损失。固定和未固定的组织样本的灵敏度相同。无论组织切片是否固定,TempO-Seq 检测都具有相同的灵敏度。该检测方法对人、鼠或大鼠的全转录组都具有等效的性能。从 5 μm 厚的切片中获得的 10mm2 和 2mm2 组织区域的结果是等效的,因此证明了该方法具有高灵敏度和在切片中聚焦组织区域的能力。根据组织类型的不同,来自不同组织区域的重复再现性的 R2 值范围从 0.83(肺)到 0.96(肝),平均相关性为 0.90,涉及 9 种组织类型。表达大于 200 个计数的基因的平均 %CV 为 16.8%,表达大于 50 个计数的基因的平均 %CV 为 20.3%。鉴定了组织特异性差异,并与文献一致。使用已归档长达 30 年的 FFPE 组织对检测性能几乎没有影响。同样,H&E 染色对检测性能几乎没有影响,便于对组织切片内的特定组织学小焦点区域进行刮取和检测。