Role of lentivirus-mediated overexpression of programmed death-ligand 1 on corneal allograft survival.
To investigate the role of lentivirus-mediated overexpression of programmed death-ligand 1 (PD-L1) on rat corneal allograft survival. A fully allogeneic rat cornea transplant model was used for in vivo studies. Lentiviral (LV) vectors are efficient tools for ex vivo genetic modification of cultured corneas. LV vector encoding for PD-L1 (LV.PD-L1) and LV vector encoding for eGFP (LV.eGFP, as control) were constructed and tested. PD-L1 or eGFP expression was increased on corneal cells upon LV.PD-L1 and LV.eGFP transduction, respectively. Both allogeneic controls and allogeneic LV.eGFP transduced corneas were uniformly rejected (MST: 13.8 ± 1.7 days and 12.3 ± 1.9 days, respectively). In contrast, allogeneic LV.PD-L1 transduced corneas showed a high percentage (83%) of graft survival (MST > 30 days, n = 5, 15 days, n = 1). Graft opacity of PD-L1 transduced corneas was present but was significantly reduced compared to control or eGFP expressing corneas. Flow cytometric analysis revealed that percentages of CD3(+) CD8(+) CD161(+)  and CD3(+) CD8(+) CD161(-)  lymphocytes were decreased in animals receiving LV.PD-L1 transduced corneas compared to animals grafted with LV.eGFP transduced corneas. Moreover, reduced expression of proinflammatory cytokines (IFN-γ and IL-6) in PD-L1 transduced corneas compared to allogeneic controls was also observed. Local PD-L1 gene transfer in cultured corneas is a promising approach for the prolongation of corneal allograft survival and attenuation of graft rejection.
College of Medicine, Nursing and Health Sciences, Regenerative Medicine Institute, National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Ireland.
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M
Nosov
M
M
Wilk
M
M
Morcos
M
M
Cregg
L
L
O'Flynn
O
O
Treacy
T
T
Ritter
D000818:Animals; D060890:B7-H1 Antigen / Q000235:genetics* / Q000276:immunology; D003315:Cornea / Q000378:metabolism*; D016039:Corneal Transplantation; D016207:Cytokines / Q000378:metabolism; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors; D006084:Graft Rejection / Q000517:prevention & control*; D006085:Graft Survival; D016086:Lentivirus / Q000235:genetics*; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D014184:Transplantation, Homologous
D060890:B7-H1 Antigen; D016207:Cytokines