[The effects of complement C3f segment on expression and secretion of collagen I, III and transforming growth factor-beta1 in human embryonic lung fibroblast].
OBJECTIVE
To observe the effects of complement fragment C3f on expression and secretion of collagen I, III and transforming growth factor( TGF)-beta1 in human embryonic lung fibroblast (MRC-5) cells.


METHODS
MRC-5 cells were cultured with C3f (the synthetic 17 peptides fragments of complement C3). The extracellular and intracellular expression levels of type I, III collagens and TGF-beta1 in MRC-5 cultures were detected by ELISA and immunohistochemistry, respectively.


RESULTS
The expression levels of type I, III collagen and TGF-beta1 in the supernatant of MRC-5 cultures decreased significantly with the concentrations of C3f as compared with controls (P < 0.05). Also the expression level of TGF-beta1 in MRC-5 cytoplasm reduced significantly as compared with controls (P < 0.05).


CONCLUSIONS
The results of present in vitro study showed that the complement fragment C3f could reduce the formation of TGF-beta1 and type I, III collagens in MRC-5 cells, and inhibit the lung tissue fibrosis.
Department of Laboratory Medicine, Tianjin Infectious Disease Hospital, Tianjin 300192, China.
Wei
W
Liu
Qing-Bo
QB
Ma
Juan-Juan
JJ
Chen
Hai-Xia
HX
Kong
Mao-Ti
MT
Wei
Shi-Xin
SX
Wang
D002460:Cell Line; D024042:Collagen Type I / Q000378:metabolism*; D024061:Collagen Type III / Q000378:metabolism*; D003179:Complement C3b / Q000494:pharmacology*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D008168:Lung / Q000166:cytology / Q000187:drug effects* / Q000196:embryology; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
D024042:Collagen Type I; D024061:Collagen Type III; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; C046821:complement C3f; D003179:Complement C3b