ANTIVIRAL ACTIVITY OF WIN-54954 IN COXSACKIEVIRUS B2 CARRIER STATE INFECTED HUMAN MYOCARDIAL FIBROBLASTS

Persistent infections with a cardiotropic enterovirus, e.g. coxsackiev irus B2 (CVB2), cause chronic myocarditis and eventually congestive he art failure. Therefore, the antiviral activity of WIN 54954, a capsid binding antiviral agent that inhibits enterovirus uncoating, was studi ed in persistently CVB2-infected cultures of human myocardial fibrobla sts. Cultures displayed a typical carrier state infection with virus t iters of 3.9 +/- 1.6 x 10(5) plaque forming units (PFU)/ml and 0.99% i nfected cells. WIN 54954 (0.025-1 mu g/ml) application was started 7 d ays after infection of the cultures. Compared to the WIN 54954 concent ration resulting in a 90% plaque number reduction (EC90 = 0.197 mu g/m l) in acutely infected Vero cells, WIN 54954 reduced virus yields of m yocardial fibroblast cultures more efficiently, e.g. more than 100 fol d (99%) with 0.025 mu g/ml after 4 days of application. Antiviral effe cts of WIN 54954 increased with application time and at 0.025 mu g/ml Win 54954 completely inhibited infectious virus progeny after 16 days. Increasing the WIN 54954 concentration up to 1 mu g/ml did not cause a greater inhibition of virus replication. In situ hybridization demon strated that at 0.1 mu g/ml WIN 54954 reduced the number of infected c ells from 0.99 to 0.18%, although a complete eradication of CVB2-infec ted cells was not achieved at concentrations as high as 1 mu g/ml. In conclusion, the results indicate that low concentrations oi WIN 54954 are effective in treating persistent enterovirus infections of myocard ial fibroblasts, although a complete eradication of the infection is n ot achieved with WIN 54954 as a single antiviral agent. (C) 1998 Elsev ier Science B.V.