Table 4. Summary of the literature.

Investigator	Time period	Biological source	Name of substance	Biological assay system	Physicochemical characteristics: (resistance)				Response organ/species	% of purification	Mrb
					Heat	Trypsin	Chymotrypsin	Neuraminidase
Blomqvist	1957	NbReLa		in vivo: NR
LaBrecque	1975–1987	WRL-ReRL	HSS	in vitro; HTC cells	Yes	No	No	Yes	Yes No	110,000	14,000–15,000
				in vivo: 40% HeR
Hatase	1979	NL		in vitro: L-929 fibroblast	No	No					30,000
				in vivo: N and 34% HeR
Starzl	1979	ReL from 70% He dog		in vivo: dog with portacaval shunt					Yes
Goldberg	1980–1985	ReL from 70% He rat	Hepatopoietin	in vivo: NR	Yes	No	No	No	Yes No	13,000	38,000
Terblanche	1980	Re dog L		in vivo: NR
Francavilla	1984–1985	WRL	HSS	in vivo: 40% HeR	Yes	No	No	Yes	Yes No	38,000	15,000–50,000
Schwarz	1985	ReL from 70% He R and Pig		in vivo: 34% He female R and WR	Yes				No		14,000–25,000
				in vitro: hepatocyte cells
Lieberman	1984	Mouse plasma membrane		in vitro: NR-6 line fibroblast	No	Yes	No	No
Fleig	1986	ReL from 60% He rabbit		in vivo: NR		No	No

^aL, liver; N, normal; Nb, newborn; R, rat; Re, regenerating; He, hepatectomized; W, weanling.

^bDetermined by SDS-polyacrylamide gel electrophoresis