CHARACTERIZATION OF HIGHLY PURIFIED, INACTIVATED HIV-1 PARTICLES ISOLATED BY ANION-EXCHANGE CHROMATOGRAPHY

This report characterizes inactivated, gp120 depleted, HIV-1 particles purified by an anion exchange chromatography production process. This antigen formulated with incomplete Freund's adjuvant constitutes Remu ne(TM), which is being evaluated in a phase III clinical endpoint tria l to determine the effect of this immune-based therapy on clinical pro gression of HIV-1 seropositive patients. Multiple production lots of t he inactivated HN-I antigen strain HZ321, isolated by anion exchange c hromatography, exhibit purity of > 95% by gel filtration. These findin gs are corroborated by thin section electron microscopy showing a homo genous field of intact particles. Analyses of the purified virus par-t ides for protein, lipid, carbohydrate and RNA show structural retentio n of the envelope proteins, lipid bilayer and core components after la rge scale processing. The qualitative identification of at least 85% o f total HIV-1 protein is determined by ELISA, Western blot HPLC and am ino acid sequencing analyses. Quantitative values are assigned to 50% of these proteins. The data confirm the presence of virally encoded pr oteins p6, p7, p(1)15, p17, p24, p32, p(1)39(Gag), gp41, p(p)55(Gag), p66/51, Vpr; Vif and Nef: Excellent consistency between production lot s and equivalency to HN-I preparations purified by sucrose density gra dient sedimentation has been established for protein and lipid composi tion, and overall purity. These findings further establish that non-vi ral encoded proteins and lipids are integral structural components of the intact virion and are not contaminants unique to a particular isol ation method. The data confirm the presence of multicomponent antigens in the viral particles for stimulating a broad HIV-1 specific immune response. Finally, the work demonstrates that the two inactivation pro cedures (beta-propiolactone and gamma irradiation), which achieve effi cient viral inactivation meeting US FDA guidelines, do not damage the protein antigens of the viral particles. (C) 1997 Elsevier Science Ltd . All rights reserved.