IN-VITRO INHIBITION OF THE REPLICATION OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 BY BETA-MERCAPTOETHYLAMINE (CYSTEAMINE)

This study investigates the effects of cysteamine alone and in associa tion with zidovudine or didanosine on the replication of human immunod eficiency virus type 1 (HIV-1). More than 90% viral inhibition was obt ained by 200 mu M cysteamine in lymphocytes and 100 mu M cysteamine in macrophages against 4 primary isolates and 2 laboratory strains of HI V-1. Polymerase chain reaction analysis demonstrated that cysteamine i nterferes with early steps of HIV-1 replication, before proviral DNA f ormation. The use of cysteamine in conjunction with zidovudine or dida nosine brought about an additive antiviral effect without concomitant increases in toxicity. The concentrations of cysteamine that are effec tive against HIV-1 in vitro have been wed tolerated over long periods by patients under treatment for cystinosis, an inherited disorder. The se observations suggest that cysteamine alone or in combination with z idovudine or didanosine could be a new potential treatment of HIV-1 in fection.