Table 1.

HBsAg expression and anti-HBs induction in the mice inoculated with DNA vaccine against hepatitis B (NV-HB/s)

	Positive rate after inoculation
	3 d	1 wk	2 wk	1 mo	2 mo	4 mo	6 mo
HBsAg (%)	0	33.3	100	75	5	83.3	75
	(0/4)	(1/3)	(3/3)	(3/4)	(3/4)	(5/6)	(6/8)
Anti-HBs (%)	0	0	66.7	100	100	100	100
	(0/4)	(0/3)	(2/3)	(4/4)	(4/4)	(6/6)	(8/8)

HBsAg was detected from mice muscle tissue samples of injection sites by ABC immunochemistry. Anti-HBs was detected from sera samples by ELISA. The numbers in parenthesis indicate the number of mice with positive detection results/the total number of mice detected.