Detection of the genome and transcripts of a persistent DNA virus in neuronal tissues by fluorescent in situ hybridization combined with immunostaining

J Vis Exp. 2014 Jan 23:(83):e51091. doi: 10.3791/51091.

Abstract

Single cell codetection of a gene, its RNA product and cellular regulatory proteins is critical to study gene expression regulation. This is a challenge in the field of virology; in particular for nuclear-replicating persistent DNA viruses that involve animal models for their study. Herpes simplex virus type 1 (HSV-1) establishes a life-long latent infection in peripheral neurons. Latent virus serves as reservoir, from which it reactivates and induces a new herpetic episode. The cell biology of HSV-1 latency remains poorly understood, in part due to the lack of methods to detect HSV-1 genomes in situ in animal models. We describe a DNA-fluorescent in situ hybridization (FISH) approach efficiently detecting low-copy viral genomes within sections of neuronal tissues from infected animal models. The method relies on heat-based antigen unmasking, and directly labeled home-made DNA probes, or commercially available probes. We developed a triple staining approach, combining DNA-FISH with RNA-FISH and immunofluorescence, using peroxidase based signal amplification to accommodate each staining requirement. A major improvement is the ability to obtain, within 10 µm tissue sections, low-background signals that can be imaged at high resolution by confocal microscopy and wide-field conventional epifluorescence. Additionally, the triple staining worked with a wide range of antibodies directed against cellular and viral proteins. The complete protocol takes 2.5 days to accommodate antibody and probe penetration within the tissue.

Publication types

  • Research Support, Non-U.S. Gov't
  • Video-Audio Media

MeSH terms

  • Animals
  • DNA, Viral / analysis
  • DNA, Viral / genetics
  • Female
  • Fluorescent Antibody Technique / methods*
  • Genome, Viral*
  • Herpesvirus 1, Human / genetics*
  • Immunoenzyme Techniques
  • In Situ Hybridization, Fluorescence / methods*
  • Mice
  • Mice, Inbred BALB C
  • Microscopy, Confocal
  • Neurons / virology*
  • RNA, Viral / analysis
  • RNA, Viral / genetics

Substances

  • DNA, Viral
  • RNA, Viral