INHIBITORY EFFECT OF BIPHALIN AND AZT ON MURINE FRIEND-LEUKEMIA-VIRUSINFECTION IN-VITRO

Biphalin is a bivalent opioid analogue containing two tyrosine residue s, We have examined the effect of biphalin's anti-retroviral potency i n vitro using a murine model. Biphalin, in non-cytotoxic concentration s, suppressed ina dose-dependent fashion the replication of Friend leu kemia virus (FLV) in Mus dunni cells as determined using a focus formi ng assay. FLV replication was substantially reduced by biphalin at 10( -4) M concentration, When biphalin was combined with 3'-azido-3'-deoxy thymidine (AZT) the two acted synergistically in inhibiting FLV replic ation compared to either used alone. Using a reverse transcriptase (RT ) assay, FLV RT levels also were noted to be reduced in the presence o f biphalin. These observations indicate that biphalin possesses anti-r etroviral activity in vitro, suggesting that this opioid peptide shoul d be examined further in vivo to determine if it is a candidate for co mbined therapy with AZT and possibly other drugs for retrovirus infect ions including the human immunodeficiency virus (HIV). (C) 1998 Intern ational Society for Immunopharmacology. Published by Elsevier Science Ltd.