单细胞RNA测序在眼角膜和视网膜疾病诊断治疗中的应用

Application of single-cell RNA sequencing in diagnosis and treatment of corneal and retinal diseases

背景:单细胞RNA测序作为新一代mRNA测序方法,经过十几年的发展已经逐渐成熟并逐步应用于眼科研究。目的:综述近年来单细胞RNA测序的发展及其在眼科学领域的应用及进展。方法:利用计算机检索PubMed,Sciencedirect及Web of Science数据库中相关文献,以“Single-cell RNA-seq,retina,cornea,gene marker”为英文检索词进行检索,检索时限为2006-01-01/2021-01-31,通过阅读和分析对文献进行初步筛选,以排除重复文献和低相关性文献,最终纳入80篇文献进行结果分析。结果与结论:①单细胞RNA测序是在单细胞水平上,对基因组、转录组和表观基因组进行高通量测序分析的技术,与传统的测序方法相比,其可进一步应用于研究细胞之间的差异,解释细胞亚型和特定表达的基因,探索疾病发生、发展和耐药机制,为免疫治疗提供新的靶点。②目前单细胞RNA测序有很多分支,如STRT-seq,Smart-seq,CEL-seq,MARS-seq,Cyto-seq,Drop-seq,inDrop-seq及Seq-Well等,这些技术各有其优势和应用领域,例如STRT-seq仅在5'端且不具有链特异性,然而Samrt-seq转录覆盖区域为全长。③在眼科学领域中,单细胞RNA测序主要应用于角膜和视网膜的研究,在眼细胞新亚型的识别以及眼科疾病的诊断和潜在的免疫治疗中均有新的科学发现,少数应用于晶状体疾病和葡萄膜黑色素瘤的研究。④单细胞RNA测序技术在角膜领域的研究,主要是关于圆锥角膜疾病、角膜上皮细胞基因的相关表达。其中,Notch1和PLLP基因被证实与圆锥角膜的发病机制相关;角膜基底细胞中Krt15,Fzd7,Krt17基因表达增高,而基底上皮祖细胞中Sox9,Actn1,Anxa3表达为主。此外,视网膜组织是一种易于获取并观察的组织,单细胞RNA测序技术近年来多被应用于研究正常视网膜组织细胞亚型,以及视网膜相关疾病,如年龄相关性黄斑病变及视网膜母细胞瘤等疾病的基因表达研究。⑤单细胞RNA测序技术可以准确反映单个细胞的基因表达情况,近年来多用于角膜和视网膜的基因表达、细胞亚型与信号通路研究,在未来的眼科疾病治疗中将发挥重要的作用。

BACKGROUND:Single-cell RNA sequencing,as a new generation of mRNA sequencing method,has gradually matured and been applied in ophthalmic research after more than ten years of development.OBJECTIVE:To review the development of single cell RNA sequencing and its application and progress in ophthalmology.METHODS:The relevant articles in PubMed,Sciencedirect,and Web of Science databases were searched by computer.English key words were“single-cell RNA-seq,retina,cornea,gene marker”.The retrieval time was from January 1,2006 to January 31,2021.The articles were screened initially through reading and analysis to exclude duplicates and low-relevance articles.Finally,80 articles were included for results analysis.RESULTS AND CONCLUSION:(1)Single cell RNA sequencing is on the single cell level,of genome,transcriptome,and epigenome high-throughput sequencing analysis technology.Compared with the conventional sequencing method,it can be further applied to study the differences between the cells,explain cell subtype and specific expression genes,to explore the disease occurrence,development and resistance mechanism,and provide new targets for the immune therapy.(2)Currently,there are many branches of single-cell RNA sequencing,such as STRT-seq,Smart-seq,CEL-seq,MARS-seq,Cyto-seq,Drop-seq,inDrop-seq,and Seq-Well.These technologies have their own advantages and application fields.For example,STRT-seq is only at the 5’end and does not have chain specificity,whereas Samrt-seq transcriptional coverage is full-length.(3)In the field of ophthalmology,single-cell RNA sequencing is mainly used in the study of cornea and retina.There are new scientific discoveries in the identification of new subtypes of eye cells and the diagnosis of ophthalmic diseases and potential immunotherapy.A few are used in the study of lens diseases and uveal melanoma.(4)The research of single-cell RNA sequencing technology in the field of cornea is mainly about keratoconus disease and corneal epithelial cell gene expression.Notch1 and PLLP genes were proven to be related to the pathogenesis of keratoconus.The expression of Krt15,Fzd7,and Krt17 genes increased in corneal basal cells,while Sox9,Actn1,and Anxa3 were mainly expressed in basal epithelial progenitor cells.In addition,retinal tissue is a kind of tissue that is easy to obtain and observe.In recent years,single-cell RNA sequencing technology has been applied to study the gene expression of normal retinal tissue cell subtypes and retinal-related diseases,such as age-related macular degeneration and retinoblastoma.(5)Single-cell RNA sequencing technology can accurately reflect the gene expression of a single cell.In recent years,it has been used to study the gene expression,cell subtypes and signaling pathways of cornea and retina,and will play an important role in the treatment of ophthalmic diseases in the future.