Abstract
Purpose: :
To determine the transcriptional responses of human corneal endothelial cells (HCEs) after herpes simplex virus type 1 (HSV-1) infection and to examine the roles of critical inflammatory element(s).
Methods: :
Immortalized HCEs were infected with HSV-1, and the global transcriptional profile determined. Molecular signaling networks were constructed from the HSV-1-induced transcriptomes. The relationships of the crucial molecules in the identified networks were examined by FACS, real time-PCR, and ELISA.
Results: :
HSV-1 infection induced a global transcriptional activation with 873 genes significantly induced or repressed compared to mock infected HCEs (P<0.05, 3< or 0.33> threshold). Network analysis identified viral infection-induced interferon response and pattern recognition receptor(PRR)-mediated signaling as most significant association in the global transcriptional responses. To understand initial events underlying HSV-1 infection, we screened for expression of toll-like receptors(TLR) as representative PRR. FACS analysis identified selective expression of TLR-9 in HCE. In the inflammatory networks, type I interferon and IL-6 was identified as crucial elements. Analysis using TLR-9-inhibitory oligonucleotide or siRNA showed that TLR-9 inhibition reduced HSV replication, and suppressed transcritptional activation of IL-6 in HCEs.
Conclusions: :
HCEs respond to HSV-1 infection by TLR9, which induces IL-6 as crucial element in the inflammatome.
Keywords: herpes simplex virus • cornea: endothelium • gene microarray