TABLE 1.

Clinical and virological course of primary HCV infection and rechallenge

Type of infection	Chimpanzee	Route of inoculationc	ALT		Viremia
			Maximum activity (U/liter)	Duration (wks) of elevationa	Maximum titerb (RNA copies/ml)	Duration (wks) (>400 copies/mla)
Primary HCV 1a inoculation	Ch4X0186	i.v.	160	>8	2 × 105	8 + 1d
	Ch1552	i.h.	249	10 + 1	1 × 107	15 + 1
	Ch1605	i.v.	176	10 + 1	1 × 106	11 + 1
Rechallenge with homologous HCV 1a	Ch4X0186	i.v.	53	2 + 1	<4 × 102	0
	Ch1552	i.v.	31	1 + 1	4 × 103	1 + 1
	Ch1605	i.v.	70	3 + 1	5 × 104	1 + 1
Rechallenge with heterologous HCV 1b	Ch4X0186	i.v.	86	1 + 1	<4 × 102	0

^aSerum samples were tested at weekly intervals; the durations of ALT elevation and viremia are therefore indicated with 1-week variance.

^bQuantitative real-time RT-PCR (sensitivity, 400 RNA copies/ml).

^ci.v., intravenous HCV infection; i.h., intrahepatic transfection with in vitro-transcribed HCV RNA.

^dRobert Lanford, personal communication.