Downregulation of Thy1 in retinal ganglion cells in experimental glaucoma.
OBJECTIVE
Thy1 is a surface glycoprotein uniquely expressed in retinal ganglion cells (RGCs) in retina. The aim of this study was to investigate the expression change of Thy1 in a model of experimental glaucoma.


METHODS
The change of protein and mRNA levels of Thy1 in the retina were studied using stereological counts of back-labeled RGCs, Western blot analysis, immunohistochemistry, and laser capture microdissection (LCM) of RGCs with quantitative PCR analysis of mRNA in a model of experimental glaucoma. LCM after optic nerve crush was also performed to evaluate Thy1 mRNA levels after a different injury.


RESULTS
After 10 days of elevated IOP, there was a 34% loss of RGC number, Thy1 protein decreased 60% in eyes with elevated intraocular pressure (IOP), and Thy1 mRNA levels decreased 51% in RGCs. Both protein and mRNA level change of Thy1 is to a much greater extent than RGC number loss.


CONCLUSIONS
The current results confirm that Thy 1 mRNA levels do not reflect the number of RGCs present and extend this to include a parallel decrease in Thy1 protein levels. These results suggest that Thy1 serves as an early marker of RGC stress, but not a marker of RGC loss, in models of retinal damage.
Howe Laboratory of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, 02114, USA.
Wei
W
Huang
John
J
Fileta
Yan
Y
Guo
Cynthia L
CL
Grosskreutz
D000818:Animals; D015153:Blotting, Western; D002452:Cell Count; D004195:Disease Models, Animal; D015536:Down-Regulation; D005901:Glaucoma / Q000378:metabolism* / Q000473:pathology; D007150:Immunohistochemistry; D007429:Intraocular Pressure; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D011914:Rats, Inbred BN; D012165:Retinal Ganglion Cells / Q000378:metabolism* / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018800:Thy-1 Antigens / Q000235:genetics* / Q000378:metabolism
D012333:RNA, Messenger; D018800:Thy-1 Antigens