TABLE 2.

Comparison of WHV antigen expression and histological changes in liver prior to experimental WHV infection and at the time of maximum acute liver injury following infection

Woodchuck	Level of viremia	WHV antigen expression (%)				Histological changes (scores)a
		WHcAg		WHsAg		Portal hepatitis		Lobular hepatitis		Bile duct proliferation		Liver cell dysplasia
		2 wk preinfection	Max serum SDH activity	2 wk preinfection	Max serum SDH activity	2 wk preinfection	Max serum SDH activity	2 wk preinfection	Max serum SDH activity	2 wk preinfection	Max serum SDH activity	2 wk preinfection	Max serum SDH activity
F3538	High	0	75	0	0.5	0	2	0	2	0	1	0	0
F3539	High	0	50	0	0.5	0	1	0	1	0	0	0	0
F3524	Intermediate	0	25	0	0.5	0	1	0	2	0	0	0	2
M3540b	Low	0	0	0	0	0	0	0	0	0	0	0	0
F3991	Low	0	0	0	0	0	2	1	2	0	0	1	1
M3553	Low	0	0	0	0	0	0	1	1	0	0	0	0

^aThe first value in each column was determined using hepatic specimens obtained 2 weeks prior to experimental WHV infection. The second value was determined using hepatic specimens obtained at or around the time of maximum serum SDH activity (see Table 1 for details). Liver biopsies were obtained from woodchucks F3991 and M3553 at 4 weeks postinfection, from woodchuck M3540 at 8 weeks postinfection, from woodchucks F3538 and F3524 at 10 weeks postinfection, and from woodchuck F3539 at 12 weeks postinfection.

^bMaximum SDH activity for woodchuck M3540 was at week 4 postinfection, whereas the presented data were derived from data for liver tissue obtained 4 weeks after the SDH peak (i.e., at 8 weeks postinfection).