title: A pilot study on expression of toll like receptors (TLRs) in response to herpes simplex virus (HSV) infection in acute retinal pigment epithelial cells (ARPE) cells.
abstract: BACKGROUND
  Toll like receptors (TLRs) have been proven to play an important role in mounting the innate immune response in an infected host. The expression of TLRs against herpes simplex virus (HSV) have not been studied in retinitis. Therefore, the current study was undertaken to determine the same using the retinal pigment epithelial (ARPE-19) cell line.
  
  
  METHODS
  APRE cells cultured in vitro were challenged with HSV 1 and 2 standard strains and 20 other clinical isolates. The cells were observed for cytopathic changes. The cell culture harvest was subjected to RNA extraction using a Total RNA mini kit. The RNA was subjected to reverse transcriptase polymerase chain reaction (PCR) for the amplification of TLRs 3, 4 and 9 and GAPDH housekeeping gene. The amplified products were subjected to electrophoresis on a 2% agarose gel and viewed under a transilluminator.
  
  
  RESULTS
  TLR 3 and 4 were expressed by ARPE treated with all the 22 isolates. TLR 9 expression was seen in 16 of the 22 isolates. Bacterial contamination was ruled out by subjecting the harvests to PCR amplification of 16sRNA gene amplification of the eubacterial genome.
  
  
  CONCLUSIONS
  The expression of TLR 4 has been reported for the first time in HSV infection. TLR 4 along with TLR 3 and 9 is responsible for the antiviral response in HSV infections.
authors.forename: S
authors.initials: S
authors.lastname: Moses
authors.affiliation: L and T Microbiology Research Center, Kamal Nayan Bajaj Research Centre, Vision Research Foundation, Chennai, Tamil Nadu, India.
authors.forename: M
authors.initials: M
authors.lastname: Jambulingam
authors.forename: H N
authors.initials: HN
authors.lastname: Madhavan
mesh_terms: D002478:Cells, Cultured; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D015828:Eye Infections, Viral / Q000378:metabolism; D005260:Female; D015967:Gene Expression Regulation, Viral; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics; D006561:Herpes Simplex / Q000378:metabolism; D018259:Herpesvirus 1, Human / Q000378:metabolism*; D006801:Humans; D010857:Pigment Epithelium of Eye / Q000276:immunology / Q000378:metabolism*; D010865:Pilot Projects; D012333:RNA, Messenger / Q000235:genetics; D012173:Retinitis / Q000378:metabolism* / Q000821:virology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051196:Toll-Like Receptor 3 / Q000235:genetics*; D051197:Toll-Like Receptor 4 / Q000235:genetics*; D051217:Toll-Like Receptor 9 / Q000235:genetics*; D051193:Toll-Like Receptors
chemical_list: D016207:Cytokines; D012333:RNA, Messenger; D051196:Toll-Like Receptor 3; D051197:Toll-Like Receptor 4; D051217:Toll-Like Receptor 9; D051193:Toll-Like Receptors; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases