Feline leukemia virus detection in corneal tissues of cats by polymerase chain reaction and immunohistochemistry.
OBJECTIVE
To determine the presence of feline leukemia virus (FeLV) in the corneas of FeLV-infected cats.


METHODS
Thirty-four random source cats.


METHODS
Seventeen cats were found positive for FeLV serum p27 antigen by enzyme-linked immunosorbent assay (ELISA). Twelve ELISA positive cats were also positive on peripheral blood samples by immunofluorescent antibody (IFA) testing. Seventeen ELISA negative cats served as negative controls. Full thickness corneal specimens were collected from the left cornea of all cats and analyzed for FeLV proviral DNA and gp70 antigen by polymerase chain reaction (PCR) and immunohistochemical (IHC) testing, respectively.


RESULTS
Eleven (64.7%) positive corneal PCR results were obtained from 17 ELISA positive cats. Of 12 cats that were both ELISA and IFA positive on peripheral blood, 10 (83.3%) had positive corneal PCR results. All corneal tissues from ELISA negative cats were PCR negative. IHC staining of corneal sections revealed the presence of FeLV gp70 in corneal tissues of nine (52.9%) ELISA positive cats. Of the 12 cats that were both ELISA and IFA positive on peripheral blood, eight (66.7%) had positive corneal IHC results. Positive IHC staining was localized to the corneal epithelium. Corneal tissues of all ELISA negative cats and all IFA negative cats were negative on IHC testing.


CONCLUSIONS
FeLV antigens and proviral DNA are present in corneal tissues of some FeLV-infected cats. Screening corneal donors for FeLV infection is warranted.
Herring
I P
IP
Department of Small Animal Clinical Sciences and Center for Molecular Medicine and Infectious Diseases, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061-0442, USA. iherring@vt.edu
Troy
G C
GC
Toth
T E
TE
Champagne
E S
ES
Pickett
J P
JP
Haines
D M
DM
D000818:Animals; D000956:Antigens, Viral / Q000302:isolation & purification; D016022:Case-Control Studies; D002371:Cat Diseases / Q000821:virology*; D002415:Cats; D003315:Cornea / Q000821:virology*; D017931:DNA Primers; D004279:DNA, Viral / Q000302:isolation & purification; D004587:Electrophoresis, Agar Gel / Q000662:veterinary; D005260:Female; D007150:Immunohistochemistry / Q000662:veterinary; D005256:Leukemia Virus, Feline / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D008297:Male; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012192:Retroviridae Infections / Q000662:veterinary* / Q000821:virology; D014412:Tumor Virus Infections / Q000662:veterinary* / Q000821:virology
D000956:Antigens, Viral; D017931:DNA Primers; D004279:DNA, Viral