The herpes simplex virus type 1 (HSV-1) glycoprotein K(gK) is essential for viral corneal spread and neuroinvasiveness.
OBJECTIVE
To determine the role of herpes simplex virus-1 (HSV-1) glycoprotein K(gK) in corneal infection, neuroinvasion, and virus latency in trigeminal ganglia of mice.


METHODS
The recombinant virus HSV-1 (McKrae) Delta gK (MKDelta gK) carrying a deletion of the gK gene was constructed by insertional/deletion mutagenesis and replaced by a gene cassette constitutively expressing the enhanced green fluorescence protein. The gK deletion of the MKDelta gK virus was rescued to produce the wild-type-like virus MKgK. Balb/c mice were infected ocularly with either virus, and the infection pattern in the eye, clinical disease progression, and establishment of viral latency was monitored.


RESULTS
Mice infected with the MKDelta gK strain produced in a gK complementing cell line did not exhibit clinical signs when compared with mice infected with the MKgK virus. Direct visualization of infected eyes revealed that the MKDelta gK virus was unable to spread in mouse corneas, while the MKgK rescued virus spread efficiently. Nineteen of 20 scarified and 5/12 unscarified mice infected with the MKgK virus produced infectious virus after coculture with permissive cells, while 0/20 scarified and 0/12 unscarified mice infected with the MKDelta gK virus produced infectious virus. HSV DNA was detected in trigeminal ganglia by PCR in 19/20 scarified and 9/12 unscarified mice inoculated with MKgK, while HSV DNA was detected in the trigeminal ganglia of 3/20 scarified and 0/12 unscarified mice inoculated with MKDelta gK.


CONCLUSIONS
The results show that HSV-1 gK is essential for efficient replication and spread in the corneal epithelium and trigeminal ganglia neuroinvasion in MKDelta gK inoculated mice.
Division of Biotechnology and Molecular Medicine, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
Andrew T
AT
David
A
A
Baghian
T P
TP
Foster
V N
VN
Chouljenko
K G
KG
Kousoulas
D000818:Animals; D018920:Coculture Techniques; D003315:Cornea / Q000294:innervation* / Q000473:pathology; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D018259:Herpesvirus 1, Human / Q000472:pathogenicity* / Q000502:physiology; D016849:Keratitis, Herpetic / Q000473:pathology / Q000821:virology*; D051379:Mice; D008807:Mice, Inbred BALB C; D016133:Polymerase Chain Reaction; D011993:Recombinant Fusion Proteins / Q000502:physiology; D012668:Trigeminal Ganglion / Q000821:virology*; D014764:Viral Proteins / Q000502:physiology*; D017735:Virus Latency; D014779:Virus Replication / Q000502:physiology
D004279:DNA, Viral; D011993:Recombinant Fusion Proteins; C072448:UL53 protein, Human herpesvirus 1; D014764:Viral Proteins