Abstract
Purpose: :
To determine if external addition of TNFα increase retinal reactive gliosis and to evaluate whether Adalimumab could diminished those modifications, in an organotypic culture of porcine retina.
Methods: :
Ninety porcine retina explants (5x5 mm), from 15 eyeballs, were cultured in Transwell® dishes. Thirty of them, used as controls, were cultured in Neurobasal A supplemented with B-27, Fetal Porcine Serum and L-Glutamine. Experimental groups involve 30 explants cocultured with 100 pg/ml of TNFα (TNF) (rpTNF-α recombinant porcine (E. coli-derived); R&D Systems, Minneapolis, MN) and other 30 explants cocultured with 100 pg/ml of TNFα plus 10 µg/ml of Adalimumab (TNF/Ada) (Humira® 40 mg/0.8 ml; Abbott Laboratories Ltd., Queenborought, UK), each supplement was added to the culture medium at day 0. Time-points of study were 3 (n=30), 6 (n=30) and 9 (n=30) days. Vertical cryostat sections, doubly immunostained with GFAP (glial fibrillary acidic protein) and CRALBP (cellular retinaldehyde-binding protein), were used for histological evaluation.
Results: :
In controls, GFAP expression corresponding to Müller cells and astrocytes, progressively increased and CRALBP remained apparently constant during culture. TNF stimulated explants revealed higher levels of GFAP along glial cells prolongations, crossing the outer limiting membrane and invading the supposed subretinal space. Most of the Müller cells presented GFAP expression. However, CRALBP was reduced during culture and almost disapeared at 9 days. Nevertheless, TNF/Ada explants showed similar GFAP and CRALBP expression levels as controls, at each time-point evaluated.
Conclusions: :
Adalimumab seems to block retinal reactive gliosis modifications, such as GFAP increase and CRALBP reduction, induced by external addition of TNFα, in an organotypic culture of porcine retina.
Keywords: Muller cells • retinal culture • cytokines/chemokines