Liposomes have been used as a method of delivering a variety of drugs to specific cellular targets. The specificity of liposomal delivery has been further enhanced by the conjugation of specific antibody to the surface of the liposome to form an immunoliposome. The binding of the specific antibody to its target results in an enhanced concentration of drug in the target microenvironment and the liposome facilitates the entry of the drug into its respective cellular target. This specificity of action results in decreased toxicity and enhanced efficacy. Previous work has shown that encapsulation of various antibiotics such as Nystatin and Amphotericin B into liposomes has resulted in decreased yields of p24 antigen in cultures of HIV-infected H9 cells as compared to the activity of unencapsulated drug. This technique of encapsulating potential antiviral agents will be extended to a potent immunomodulatory cytokine with known antiviral properties, namely interferon-gamma (IFNg). Liposomes or immunoliposomes (liposomes conjugated to anti-HIV antibody) containing IFNg will be incubated with HIV-infected H9 cells for seven days at which time the supernatants will be harvested and assayed for p24 production. The efficacy of the encapsulated drug (IFNg) will be compared with that of the unencapsulated drug. If results are promising, that is, encapsulated IFNg does decrease viral yield, then these liposomes may be used in cultures of lymphocytes isolated from HIV-infected individuals to see if similar antiviral activity occurs in a primary cell culture.
