Changes of collagen and MMP-1 in liver, lung and kidney during growth of mice / 生物工程学报

The high performance liquid chromatography (HPLC) and enzyme-linked immunoassay (ELISA) were used to investigate the changes of collagen and matrix metalloproteinase-1 (MMP-1) in liver, lung and kidney during growth process of mice. The mice from 0 to 18 weeks were used as the research objects. The contents and proportions of hydroxyproline (Hyp), which were used to calculate the collagen contents, in liver, lung and kidney of different weeks were analyzed with HPLC. The contents and activity of MMP-1 in liver, lung and kidney of different weeks were analyzed with ELISA. The results showed that the collagen contents in liver, lung, and kidney were different (Lung(COL)>Kidney(COL)>Liver(COL)), and they all increased first and then decreased with weeks. The collagen contents in liver, lung, and kidney reached the highest level in the ninth (5.52 ng/mg), sixth (54.10 ng/mg) and ninth (19.20 ng/mg) week, respectively. Then it declined slowly from 9 to 18 weeks. The result of ELISA showed that the MMP-1 contents in liver, lung and kidney decreased first and then increased with weeks, and the trend of MMP-1 activity was opposite. It indicated that the increase of collagen contents in the tissues will inhibit the secretion of MMP-1.

Immunological regulation of CD70/CD27 pathway and the expression of CD70 in tumor / 国际肿瘤学杂志

CD70/CD27 pathway plays an important role in human immune regulation.The role of CD70/CD27 pathway in immune regulation is mainly to promote the activation and proliferation of T cells,induce the differentiation and formation of effector T cells and memory T cells,and interfere with regulatory T cells.In addition,the high level of CD70 expression in some tumor cells provides a new way for tumor immunotherapy.

Collagen quantitation by detection of marker peptides with HPLC-MS / 生物工程学报

A method for quantitation of collagen was established by detecting marker peptide with high performance liquid chromatography-mass spectrometry (HPLC-MS). Theoretical marker peptides were selected by sequence comparison. Bovine collagen type I was digested with trypsin. Marker peptides typical for collagen type I were identified with HPLC-MS. The relationship between the abundance of marker peptides and collagen concentration was established. The results show that GEAGPSGPAGPTGAR and the other 5 peptides showed high resolution during chromatographic separation and high signal intensity during MS analysis. Peptide signal intensity and collagen concentration showed a good linear relationship in the range from 0.1 to 3 mg/mL. Bovine tendon and collagen sponge were used as actual samples and collagen contents were determined as 90.2% and 93.4% respectively. Quantitation of marker peptides of collagen was a feasible method to identify and quantify collagens in medical device research and development.

Purification of recombinant human antithrombin III expressed in a goat mammary bioreactor / 生物工程学报

Antithrombin III (AT III) is the most important anti-clotting substance. Recombinant human antithrombin III (rhAT III) expressed in transgenic goat milk attracts more and more attention. Develop an effective purification route for rhAT III is vital to its industrial production. An efficient purification method was developed for the rapid purification of rhAT III by isoelectric precipitation and heparin affinity chromatography. First, casein was effectively removed by isoelectric precipitation. rhAT III was further purified by heparin affinity chromatography. In the process of heparin affinity chromatography, the effects of pH and temperature on the stability of rhAT III were studied, and the effects of operating conditions, elution gradient, flow rate and sample loaded, on the purification efficiency were also studied. Under the optimized conditions, the protein recovery of rhAT III was about 90% with purity over 99%, while its activity recovery was about 50%. Such a purification process is very simple and effective, and it would provide a valuable reference for the further scaling-up of industrial production.

The expressions of matrix metalloproteinase and their inhibitor,and ICAM-1,VCAM-1 in lung tissue associated with COPD / 中国实用内科杂志

Objective To investigate the change of MMP-9,TIMP-1,ICAM-1 and VCAM-1 expression in serum from patients with COPD,as well as the correlation between the expressions of these factors and lung function.Methods Enzyme-linked Immunosorbent Assay(ELISA)was used to determine the levels of MMP-9,TIMP-1,ICAM-1 and VCAM-1 in serum from 58 patients with COPD and 30 samples from healthy donors in order to better understand the correlation between the expression of these factors and airflow obstruction.Results The serum levels of MMP-9,TIMP-1,ICAM-1 and VCAM-1[(128.89?115.84),(228.28?107.13),(203.98?70.37) and (352.98?117.73)?g/L]from patients with COPD were statistically and significantly higher than the control group[(30.65?18.43),(133.69?41.41),(148.35?23.77) and (233.57?36.65)?g/L],P