Abstract
Abstract: :
Purpose: The study was undertaken to examine the effect of antisense oligonucleotides (ASON) targeting TNF-α on lymphatic cells derived from herpes simplex virus-1 infected mice. It was also investigated if these ASON could be used in vivo for a corneal treatment. Methods: BALB/c mice were corneally infected with HSV-1. Single cell suspensions were prepared from regional lymph-nodes and spleens at day 14 post infection (p.i.). The cells were co-cultured with antisense oligonucleotides (ASON), randomized control oligonucleotides (CON) or medium. CON and ASON concentrations ranged from 0.5 to 20 µM. 24 hours later, the TNF-α content of the cell culture supernatants was determined by ELISA technique. The uptake of FITC-labeled ASON was investigated by fluorescence microscopy and FACScan analysis. In vivo, the distribution of the fluorescence was studied after subconjunctival or intracorneal injection of FITC-labeled ASON or FITC alone. The distribution of the fluorescence was studied histologically 1, 2, 7, and 10 days after the injection. Results: ASON entered the target cells rapidly. As revealed by fluorescence microscopy and by FACScan analysis, over 90% of the cells were positively stained after 30 min. The optimal concentration to downregulate TNF-α in cell culture conditions was 5 µM. There was no cytopathologic effect detectable in the target cells. Medium did not produce any effect while CON caused slight side-effects. The fluorescent staining within the mouse eye disappeared 2 days after a single injection of FITC. After a single injection of FITC-ASON, an enhanced staining was still detectable at day 10, indicating a prolonged activity in the cornea. Inflammatory side effects were not observed. Conclusions: Antisense oligonucleotides targeting TNF-α appear to be a useful approach to suppress this pro-inflammatory cytokine in vitro and may be used in animal models for corneal diseases.
Keywords: cytokines/chemokines • herpes simplex virus • immunomodulation/immunoregulation