We investigated the efficiency of activated polyamidoamine maximal after transfection with 18:1 (w/w) activated dendrimers, a new class of nonviral vectors, to transfect dendrimer:plasmid DNA ratio and culture for 3 days. The rabbit and human corneas in ex vivo culture. In addition to supernatant of corneas transfected with TNFR-Ig plasmid assessing the expression of a marker gene we have demcontained TNFR-Ig protein which was able to inhibit TNFonstrated that this approach can be used to induce the promediated cytotoxicity in a bioassay. We have therefore duction of TNF receptor fusion protein (TNFR-Ig), a protein shown that activated dendrimers are an efficient nonviral with therapeutic potential. Whole thickness rabbit or human vector capable of transducing corneal endothelial cells ex corneas were transfected ex vivo with complexes convivo. They may have applications in gene-based sisting of dendrimers and plasmids containing lacZ or approaches aimed at prevention of corneal allograft TNFR-Ig genes. Following optimisation 6-10% of the correjection or in treatment of other disorders of corneal neal endothelial cells expressed the marker gene.endothelium. Expression was restricted to the endothelium and was

There is an early cytokine and chemokine response to the transplantation process, evident in syngeneic and allogeneic grafts, that probably drives angiogenesis, leukocyte recruitment, and affects leukocyte functions. After an immune response has been generated, allogeneic rejection results in the expression of Th1 cytokines (IL-2, IL-12 p40, IFN-gamma), Th2 cytokines (IL-4, IL-6, IL-10, and IL-13), and antiinflammatory/Th3 cytokines (TGF-beta1/2 and IL-1RA).

Aim-To determine whether the addition of systemic corticosteroid to local intensive corticosteroid therapy of endothelial corneal allograft rejection improves outcome. Methods-A prospective randomised treatment trial was carried out at a tertiary referral centre. 36 consecutive corneal graft recipients, presenting with a first episode of endothelial graft rejection, received either (i) one intravenous pulse of methylprednisolone 500 mg in addition to local corticosteroid treatment, or (ii) local treatment only. The regimen of local treatment standardised in all cases for the first 24 hours consisted of one subconjunctival betamethasone 2 mg injection and dexamethasone 0.1% drops in the aVected eye every hour for 24 hours. Results-Failure to reverse the graft rejection episode was found in 3/36 (8%) patients. Each of these had been treated with local steroid only. Graft failure from any cause occurred in 9/36 (25%) within 2 years of follow up. No statistically significant diVerence was found between the two groups with regard to reversal of the graft rejection episode, later recurrence of graft rejection, or graft failure. Conclusions-In treatment of graft rejection, additional systemic treatment with 500 mg methylprednisolone yields no significant benefit over intensive local corticosteroid alone. Graft survival following treatment of a rejection episode with local corticosteroid treatment alone is good in those patients without other risk factors for graft failure and much higher than reported previously. (Br J Ophthalmol 1999;83:1348-1352 Five year actuarial corneal graft survival in the largest reported cohort is 74%.

Gene transfer to the corneal endothelium has potential for modulating rejection of corneal grafts. It can also serve as a convenient and useful model for gene therapy of other organs. In this article we review the work carried out in our laboratory using both viral and nonviral vectors to obtain gene expression in the cornea.

AAV is a promising vector, but its usefulness for corneal transduction is currently limited by the technical difficulties preparing high titres. The HSV vector examined is efficient but needs further genetic modification to prolong transgene expression and reduce its toxicity.