[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). CONCLUSION: 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.

[Correlation analysis between the exposure levels and the serum protein fingerprints in population exposure to silica].

OBJECTIVE: To explore the correlation between the exposure levels and serum protein fingerprints in population exposed to silica. METHODS: Liquid chip time-of-flight mass spectrometry technology was used to investigate the serum profiles in control group (30 cases), group exposed to silica (30 cases), silicosis group (I stage, 25 cases) and suspected silicosis group (30 cases), and screen the differential expression proteins. The correlation between the levels of the differential expression proteins and the exposure levels was performed. RESULTS: Five differential expression proteins were found among 4 groups, the expression of 5081 and 5066 proteins was upregulated, and the expression of 3954, 2021 and 1777 proteins was downregulated. There was no the correlation between the exposure levels and the peak with M/Z among those proteins. CONCLUSION: the results of present investigation indicated there was no correlation between the exposure levels and protein/peptide peak.