Synthesis of insulin-like growth factor binding proteins and of the acid-labile subunit of the insulin-like growth factor ternary binding protein complex in primary cultures of human hepatocytes.
J Hepatol
; 23(4): 424-30, 1995 Oct.
Article
em En
| MEDLINE
| ID: mdl-8655960
ABSTRACT
BACKGROUND/AIMS:
The liver is the main source of circulating insulin-like growth factor binding proteins. In man, the cellular origin of insulin-like growth factor binding proteins has remained obscure.METHODS:
Human hepatocytes isolated from surgical specimens were purified and cultured using a collagen gel immobilization technique. Gene expression of individual insulin-like growth factor binding proteins and of the acid-labile subunit of the insulin-like growth factor binding proteins by Western ligand blotting and immunoblot analysis. Neutral size chromatography of medium samples was used to detect insulin-like growth factors binding protein complexes.RESULTS:
In cultured hepatocytes transcripts for insulin-like growth factor binding protein-1, -2, -3, -4 and for acid labile subunit could be demonstrated. Ligand blotting revealed the secretion of insulin-like growth factor binding proteins of molecular weights of 24 kD, 30 kD, 34 kD, 43 kD and 46 kD, respectively. Using polyclonal antisera, these proteins were identified as insulin-like growth factor binding protein-1, -2 and the insulin-like growth factor binding protein-3 doublet. Neural size chromatography of culture supernatants showed the presence of an insulin-like growth factor binding protein complex of approximately 40 kD, but absence of the high molecular weight ternary complex of 150 kD.CONCLUSIONS:
It is concluded that in man parenchymal liver cells have to be regarded as a source of acid-labile subunit and of circulating insulin-like growth factor binding proteins including insulin-like growth factor binding protein-3.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Glicoproteínas
/
Proteínas de Transporte
/
Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina
/
Fígado
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
J Hepatol
Assunto da revista:
GASTROENTEROLOGIA
Ano de publicação:
1995
Tipo de documento:
Article
País de afiliação:
Alemanha