Posttranslational modifications and secretion efficiency of immunogenic hepatitis B virus L protein deletion variants

Table 1 Secretion of L protein deletion variants

	Secreted, OD₄₉₂		Intracellular, OD at 492 nm	Ratio secreted/intracellular*
L deletion variant	MAbs
	MA18/7	C20/02	MA18/7
1-48preS/S, myr wt	1.10 ± 0.16	1.00 ± 0.12	1.08 ± 0.08	1.06 ± 0.09
G2A 1-48preS/S, myr^-	0.52 ± 0.06	0.56 ± 0.09	0.69 ± 0.04	0.78 ± 0.04**
G2S 1-48preS/S, myr^-	0.67 ± 0.08	0.43 ± 0.06	1.14 ± 0.09	0.60 ± 0.06**
1-48preS/S₀, myr wt	0.17 ± 0.01	0.14 ± 0.01	0.72 ± 0.10	0.25 ± 0.07

Huh7 cells were infected at MOI 10 with rSFV encoding respective proteins. 18 h after infection cell medium was collected and replaced with a fresh medium. This was collected after 24 h and cells were lysed with a buffer containing 0.5% Triton X-100, 150 mM NaCl, 50 mM Tris–HCl pH 7.5, 2 mM EDTA and 1 μg/ml phenylmethanesulfonylfluoride. Huh7 cell lysates with 5 μg/ml cell protein and 100 μl of 2 ml of medium were analyzed by ELISA on microtiter plates coated with MAbs MA18/7 and C20/02. OD₄₉₂ of cell lysates tested on mictrotiter plate coated with C20/02 was barely above cut-off (OD at 492 nm = 0.1) for all 1-48preS/S proteins and therefore not shown. Mean values are shown ± SD.
* Ratios were calculated with OD₄₉₂ values obtained with ELISA using MAb MA18/7.
** The difference to 1-48preS/S myr wt is significant at α = 0.05.

ISSN: 1743-422X