Fig 1.

Expression of wt- and vtHBsAgs with amino acid substitutions at position 145 or 122. Huh7 cells were transfected with the expression plasmids pHBsAgWT, pHBsAgK122X (including 122G, 122M, 122L, 122I, 122P, 122N, 122Q, 122T, 122D, 122E, 122W, and 122H), and pHBsAgG145X (including 145M, 145L, 145I, 145P, 145N, 145Q, 145T, 145D, 145E, 145W, 145H, and 145R). Culture supernatants and lysates of Huh7 cells were collected at 48 h after transfection. HBsAgs were detected by a monoclonal mouse antibody to the HA tag for the expression analysis. Beta-actin was used as a loading control. CK, cells transfected with empty plasmid as a negative control. The levels of HBsAg expression were quantified by densitometry, normalized against beta-actin, and expressed in arbitrary units. The relative expression levels of vtHBsAg in supernatants and cell lysates of transfected cells were calculated as a percentage of the level of wtHBsAg expression.