Isolation and characterization of insulin-like growth factor-II from human bone.
Human bone was sequentially extracted with 4 M guanidine hydrochloride to remove nonmineralized tissue components, 0.5 M EDTA to dissolve the mineral phase, 4 M guanidine hydrochloride to remove matrix associated proteins and finally a combination of 4 M guanidine hydrochloride and 0.5 M EDTA to remove residual proteins. The extracts were examined for the presence of factors that were able to stimulate the incorporation of [3H] thymidine into DNA and [14C] leucine into protein in a cloned rat bone cell culture system. The majority of the bioactivity was found in the first guanidine hydrochloride extract (59 +/- 12%) while the second guandine hydrochloride extract contained 27 +/- 8%. In addition to several known growth factors already reported to be present in bone (transforming growth factor-beta and insulin-like growth factor-I) insulin-like growth factor-II was identified by its chromatographic, electrophoretic and immunological properties as well as by N-terminal sequence data. The insulin-like growth factor-II levels (802 +/- 112 micrograms/kg wet weight bone) were 10 fold higher than that found for insulin-like growth factor-I (84 +/- 23 micrograms/kg wet weight).
Frolik
C A
CA
Department of Biochemistry, Eli Lilly and Company, Indianapolis, Indiana 46285.
Ellis
L F
LF
Williams
D C
DC
D000818:Animals; D001842:Bone and Bones / Q000032:analysis*; D002460:Cell Line; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D007335:Insulin-Like Growth Factor II / Q000302:isolation & purification*; D007930:Leucine / Q000378:metabolism; D008970:Molecular Weight; D010455:Peptides / Q000032:analysis; D051381:Rats; D013002:Somatomedins / Q000302:isolation & purification*; D015291:Transforming Growth Factors
D010455:Peptides; D013002:Somatomedins; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II; D015291:Transforming Growth Factors; D007930:Leucine