Electron Microscopy Methods for Virus Diagnosis and High Resolution Analysis of Viruses

Abstract

The term “virosphere” describes both the space where viruses are found and the space they influence, and can extend to their impact on the environment, highlighting the complexity of the interactions involved. Studying the biology of viruses and the etiology of virus disease is crucial to the prevention of viral disease, efficient and reliable virus diagnosis, and virus control. Electron microscopy (EM) is an essential tool in the detection and analysis of virus replication. New EM methods and ongoing technical improvements offer a broad spectrum of applications, allowing in-depth investigation of viral impact on not only the host but also the environment. Indeed, using the most up-to-date electron cryomicroscopy methods, such investigations are now close to atomic resolution. In combination with bioinformatics, the transition from 2D imaging to 3D remodeling allows structural and functional analyses that extend and augment our knowledge of the astonishing diversity in virus structure and lifestyle. In combination with confocal laser scanning microscopy, EM enables live imaging of cells and tissues with high-resolution analysis. Here, we describe the pivotal role played by EM in the study of viruses, from structural analysis to the biological relevance of the viral metagenome (virome).

Comparative study on three viral enrichment approaches based on RNA extraction for plant virus/viroid detection using high-throughput sequencing

“…However, divergent sequences or virus variants with different antigenic epitopes on the virion surface would not be detected using these methods. Electron microscopy is important for viruses' detection, as it requires no prior knowledge for virus detection [7,8]. Nevertheless, it tends not to be able to identify viruses up to species level as its detection is based on the particle morphology, and often fails to detect low titre viruses or viruses that are phloem-limited and disease-causing entities without protein shells such as viroids or satellite RNAs [9,8,10,11].…”

Recent advances in lab-on-a-chip technologies for viral diagnosis

“…1D) (Cyrklaff et al, 2005) has for a long time been considered an efficient tool for viral particle identification, given its characteristic morphology and quantification by counting the viral particles (Richert-P€ oggeler et al, 2019). 1D) (Cyrklaff et al, 2005) has for a long time been considered an efficient tool for viral particle identification, given its characteristic morphology and quantification by counting the viral particles (Richert-P€ oggeler et al, 2019).…”

Potential Diagnostic Systems for Coronavirus Detection: a Critical Review

“…Transmission electron microscopy (TEM) is a good primary step in virus diagnosis, which targets proteins within the virus structure and is harmless to RNA or DNA genomes. Immuno-electron microscopy (IEM) is also based on the same serological principles as ELISA and can be a useful approach for more virus identification [59].…”