title: Interferon-gamma (IFN-γ)-mediated retinal ganglion cell death in human tyrosinase T cell receptor transgenic mouse.
abstract: We have recently demonstrated the characterization of human tyrosinase TCR bearing h3T-A2 transgenic mouse model, which exhibits spontaneous autoimmune vitiligo and retinal dysfunction. The purpose of current study was to determine the role of T cells and IFN-γ in retina dysfunction and retinal ganglion cell (RGC) death using this model. RGC function was measured by pattern electroretinograms (ERGs) in response to contrast reversal of patterned visual stimuli. RGCs were visualized by fluorogold retrograde-labeling. Expression of CD3, IFN-γ, GFAP, and caspases was measured by immunohistochemistry and Western blotting. All functional and structural changes were measured in 12-month-old h3T-A2 mice and compared with age-matched HLA-A2 wild-type mice. Both pattern-ERGs (42%, p = 0.03) and RGC numbers (37%, p = 0.0001) were reduced in h3T-A2 mice when compared with wild-type mice. The level of CD3 expression was increased in h3T-A2 mice (h3T-A2: 174 ± 27% vs. HLA-A2: 100%; p = 0.04). The levels of effector cytokine IFN-γ were also increased significantly in h3T-A2 mice (h3T-A2: 189 ± 11% vs. HLA-A2: 100%; p = 0.023). Both CD3 and IFN-γ immunostaining were increased in nerve fiber (NF) and RGC layers of h3T-A2 mice. In addition, we have seen a robust increase in GFAP staining in h3T-A2 mice (mainly localized to NF layer), which was substantially reduced in IFN-γ ((-/-)) knockout h3T-A2 mice. We also have seen an up-regulation of caspase-3 and -9 in h3T-A2 mice. Based on our data we conclude that h3T-A2 transgenic mice exhibit visual defects that are mostly associated with the inner retinal layers and RGC function. This novel h3T-A2 transgenic mouse model provides opportunity to understand RGC pathology and test neuroprotective strategies to rescue RGCs.
authors.affiliation: Hewitt Laboratory of the Ola B. Williams Glaucoma Center, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Shahid
authors.initials: S
authors.lastname: Husain
authors.affiliation: Hewitt Laboratory of the Ola B. Williams Glaucoma Center, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Yasir
authors.initials: Y
authors.lastname: Abdul
authors.affiliation: Department of Surgery, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Christine
authors.initials: C
authors.lastname: Webster
authors.affiliation: Department of Surgery, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Shilpak
authors.initials: S
authors.lastname: Chatterjee
authors.affiliation: Department of Surgery, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Pravin
authors.initials: P
authors.lastname: Kesarwani
authors.affiliation: Department of Surgery, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Shikhar
authors.initials: S
authors.lastname: Mehrotra
mesh_terms: D000818:Animals; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007150:Immunohistochemistry; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D014442:Monophenol Monooxygenase / Q000235:genetics / Q000378:metabolism*; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000378:metabolism*; D012160:Retina / Q000166:cytology / Q000378:metabolism; D012165:Retinal Ganglion Cells / Q000166:cytology* / Q000378:metabolism*
chemical_list: D011948:Receptors, Antigen, T-Cell; D007371:Interferon-gamma; D014442:Monophenol Monooxygenase