FIG. 3.

Infectivity of HDV particles coated with N-glycan-defective HBV envelope proteins based on RNA blot hybridization analysis of HDV RNA extracted from primary hepatocytes exposed to S-HDV, SL-HDV, and ngSL-HDV particles. In this experiment, 2 × 10⁶ cells were exposed to approximately 10⁸ genome equivalents of wt or mutant HDV particles. Infection assays were performed in duplicate cultures. Five micrograms (1:5) of total cellular RNA extracted from 10⁶ cells harvested 12 days after inoculation was analyzed for the presence of genomic (A) or antigenomic (B) HDV RNA. RNA extracted from 0.5 ml of inoculum was analyzed under the same conditions. RNA was separated on a 1.5% agarose-2.2 M formaldehyde gel, transferred to nylon membranes, and hybridized to strand-specific ³²P-labeled HDV RNA probes. Following hybridization, the filters were washed, dried, and autoradiographed at −70°C for 12 h with an intensifying screen. The size in kilobases of HDV genomic and antigenomic RNA is indicated.