Human adenovirus type 37 and the BALB/c mouse: progress toward a restricted adenovirus keratitis model (an American Ophthalmological Society thesis).
OBJECTIVE
To establish a mouse model of adenovirus keratitis in order to study innate immune mechanisms in the adenovirus-infected cornea.


METHODS
Balb/c 3T3 fibroblasts were inoculated with human adenovirus (HAdV) serotypes 8, 19, or 37 and observed for cytopathic effect. Viral growth titers were performed, and apoptosis was measured by TUNEL assay. Viral and host cytokine gene expression was assessed by RT-PCR in cultured Balb/c 3T3 fibroblasts and in the corneas of virus-injected Balb/c mice. Western blot analysis was performed to detect cell signaling in the virus-infected cornea.


RESULTS
Only HAdV37 induced cytopathic effect in mouse cells. Viral gene expression was limited, and viral replication was not detected. Apoptotic cell death in HAdV37-infected Balb/c cells was evident 48 and 72 hours postinfection (P < .01). MCP-1, IL-6, KC, and IP-10 mRNA levels were increased maximally by 8.4, 9.6, 10.5, and 20.0-fold, respectively, at 30 to 90 minutes after HAdV37 infection. Similar cytokine elevations were observed in the corneas of Balb/c mice 4 hours after stromal injection of HAdV37, when viral gene expression for the viral capsid protein IIIa was not detected. Western blot showed increased phosphorylation of ERK1/2 at 4 and 24 hours after corneal infection.


CONCLUSIONS
Despite limited viral gene expression, HAdV37 infection of Balb/c 3T3 fibroblasts results in increased proinflammatory gene expression. A similar pattern of cytokine expression in the corneas of HAdV37-infected Balb/c mice suggests the mouse adenoviral keratitis model may be useful for the study of early innate immune responses in the adenovirus-infected corneal stroma.
Chodosh
James
J
Molecular Pathogenesis of Eye Infection Research Center, Dean A. McGee Eye Institute, Departments of Ophthalmology, Cell Biology, Microbiology, and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.
D000257:Adenoviridae Infections / Q000378:metabolism / Q000821:virology; D000260:Adenoviruses, Human / Q000502:physiology*; D000818:Animals; D017209:Apoptosis; D041702:BALB 3T3 Cells / Q000473:pathology / Q000821:virology; D015153:Blotting, Western; D018932:Chemokine CCL2 / Q000235:genetics; D054360:Chemokine CXCL1; D054357:Chemokine CXCL10; D019743:Chemokines, CXC / Q000235:genetics; D003588:Cytopathogenic Effect, Viral; D004195:Disease Models, Animal; D015828:Eye Infections, Viral / Q000378:metabolism / Q000821:virology; D015967:Gene Expression Regulation, Viral / Q000502:physiology; D020287:In Situ Nick-End Labeling; D015850:Interleukin-6 / Q000235:genetics; D007634:Keratitis / Q000378:metabolism / Q000821:virology*; D051379:Mice; D008807:Mice, Inbred BALB C; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D010766:Phosphorylation; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014779:Virus Replication
C491768:Ccl2 protein, mouse; D018932:Chemokine CCL2; D054360:Chemokine CXCL1; D054357:Chemokine CXCL10; D019743:Chemokines, CXC; C475895:Cxcl1 protein, mouse; D015850:Interleukin-6; D012333:RNA, Messenger; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3