Interleukin 2 mediates stimulation of complement C3 biosynthesis in human proximal tubular epithelial cells.
J Clin Invest
; 88(2): 379-84, 1991 Aug.
Article
em En
| MEDLINE
| ID: mdl-1864952
ABSTRACT
Previous reports have suggested the production of complement components C4, C2, and factor B by renal tissue. However, the cells involved in production of complement have not been identified. In this study metabolic labeling experiments demonstrated that human proximal tubular epithelial cells (PTEC) synthesize a 180-kD precursor of C3 that is secreted after proteolytic cleavage into a disulphide linked two-chain molecule as found in plasma. C3 present in culture supernatants of PTEC was functionally active, however, during the culture period there was a partial inactivation of the C3 molecule as assessed by hemolytic titration. Recombinant IL-2 enhances the rate of C3 synthesis in a dose-dependent manner reaching maximal stimulation at doses of 200-400 U/ml IL-2. Northern blot analysis demonstrated a 5.2-kb C3 mRNA species present in PTEC that was increased within 24 h of IL-2 treatment. IL-2-induced enhancement of C3 production by PTEC could be neutralized with specific antibodies to IL-2. This study demonstrates that C3 synthesis in PTEC is upregulated by IL-2, the major cytokine produced by activated T cells.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Complemento C3
/
Interleucina-2
/
Túbulos Renais Proximais
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
1991
Tipo de documento:
Article