Local ocular immunomodulation resulting from electrotransfer of plasmid encoding soluble TNF receptors in the ciliary muscle.
OBJECTIVE
Plasmid electrotransfer in the ciliary muscle allows the sustained release of therapeutic proteins within the eye. The aim of this study was to evaluate whether the ocular production of TNF-alpha soluble receptor, using this nonviral gene therapy method, could have a beneficial local effect in a model of experimental autoimmune uveoretinitis (EAU).


METHODS
Injection of a plasmid encoding a TNF-alpha p55 receptor (30 microg) in the ciliary muscle, combined with electrotransfer (200 V/cm), was carried out in Lewis rat eyes 4 days before the induction of EAU by S-antigen. Control eyes received naked plasmid electrotransfer or simple injection of the therapeutic plasmid. The disease was evaluated clinically and histologically. Cytokines and chemokines were analyzed in the ocular media by multiplex assay performed 15 and 21 days after immunization.


RESULTS
Ocular TNF-alpha blockade, resulting from the local secretion of soluble receptors, was associated with delayed and significantly less severe uveitis, together with a reduction of the retinal damages. Compared with the controls, treated eyes showed significantly lower levels of IL-1beta and MCP1, higher levels of IL-13 and IL-4, and reduced NOS-2 expression in infiltrating cells. Treatment did not influence TNF-alpha levels in inguinal lymph nodes.


CONCLUSIONS
Taken together, these results indicate that local immunomodulation was achieved and that no systemic adverse effects of TNF-alpha blockade observed after systemic injection of TNF-alpha inhibitors should be expected.
Kowalczuk
Laura
L
INSERM UMRS 872 Team17, Centre de Recherches des Cordeliers, Université Pierre et Marie Curie, Université Paris Descartes, Paris, France.
Touchard
Elodie
E
Camelo
Serge
S
Naud
Marie-Christine
MC
Castaneda
Beatriz
B
Brunel
Nadege
N
Besson-Lescure
Bernadette
B
Thillaye-Goldenberg
Brigitte
B
Bigey
Pascal
P
BenEzra
David
D
de Kozak
Yvonne
Y
Behar-Cohen
Francine
F