FIG. 1.
Elution profiles of both the microvesicle-contaminated HIV-1LAV-1 preparation and microvesicles alone, protein profiles of the subtilisin-treated HIV-1LAV-1 preparation and microvesicles alone, and HIV-1 reverse transcriptase activity assay results. (A) Elution profiles of the microvesicle-contaminated HIV-1LAV-1 preparation (circles) and microvesicles alone (squares) determined with a 10-ml column of Sepharose CL-4B. OD, optical density. (B) SDS-PAGE of the microvesicle-contaminated HIV-1LAV-1 preparation and microvesicles alone derived from CEM cells. Lanes containing non-subtilisin-treated and subtilisin-treated materials are denoted by minus and plus signs, respectively. (C) Western immunoblot analysis of the subtilisin-treated HIV-1LAV-1 preparation. Antibodies used for analyses are displayed above the blots. The bands were visualized by means of chemiluminescence detection (NEN Life Science Products, Inc., Boston, Mass.). Lanes containing non-subtilisin-treated and subtilisin-treated HIV-1LAV-1 materials are denoted by minus and plus signs, respectively. RT66, reverse transcriptase. SDS-PAGE and Western immunoblot analyses of digests were done with samples containing 1 μg of starting total protein. (D) Reverse transcriptase (RT) activity of each fraction containing non-subtilisin-treated (gray bars) or subtilisin-treated (black bars) HIV-1LAV-1, determined in accordance with the manufacturer’s instructions.