HIV infection is blocked in vitro by recombinant soluble CD4

Abstract

The T-cell surface glycoprotein, CD4 (T4), acts as the cellular receptor for human immunodeficiency virus, type 1 (HIV-1), the first member of the family of viruses that cause acquired immunodeficiency syndrome^1–4. HIV recognition of CD4 is prob-ably mediated through the virus envelope glycoprotein (gp!20) as shown by co-immunoprecipitation of CD4 and gp!20 (ref. 5) and by experiments using recombinant gp!20 as a binding probe⁶. Here we demonstrate that recombinant soluble CD4 (rsT4) purified from the conditioned medium of a stably transfected Chinese hamster ovary cell line is a potent inhibitor of both virus replication and virus-induced cell fusion (syncytium formation). These results suggest that rsT4 is sufficient to bind HIV, and that it represents a potential anti-viral therapy for HIV infection.