ABSTRACT
Objective: To screen the changes of immune-associate genes expression which is related with the ageing using cDNA microar-ray.Methods:The mRNA from the spleens of young and aged rats were extracted respectively and reversely transcribed to cDNAs with the incorporation of different fluorescent-labeled dUTP as the hybridization probes. The mixed probes were hybridized to the cDNA microarray that contains the cDNA products of 416 immune-associated genes. After high-stringent washing, the cDNA microarray was scanned for the fluorescent signals and showed the gene expression differences between the young and the aged. Some biochemical assays were used to confirm the physiological differences between the young rats and the aged rats. Results: Among the examined genes, 13 down-regulated genes were identified. These genes correlated with immuned response, cell proliferation, cell differentiation and DNA/RNA repair. Only one gene which encoded ?-amylase was much higher in the aged than that in the young. Conclusion: Further analysis of the differenially expressed immune-associated genes based on cDNA microarray will be helpful for understanding the molecular mechanism of the ageing.
ABSTRACT
AIM: To study the effect of Liuwei Dihuang Wan (LWDHW) on the expression of immune-associated genes in the aged rats using cDNA microarray. METHODS: Forty 20-months-old rats were divided into two groups equally. One group was treated with LWDHW for 5 weeks,another was untreated as control. Some biochemical assays were used to confirm the physiological differences between two groups. The mRNA from the spleens of twenty 4-months-old young rats were extracted and divided equally into two parts. Each part was conjoined with mRNA from drug treated aged rats and that from untreated control aged rats,respectively,and two experimental combinations for reverse transcription and cDNA microarray were formed. By comparing two groups of data from two combinations,the effects of LWDHW on the expression of the associated genes were evaluated. RESULTS: 13 down-regulated genes and one up-regulated gene were identified in the untreated control old rats,whose expression did not change obviously in treated old rats compared with young rats. The expressions of another two sequence were up-regulated distinctly in treated old rats compared with young rats. CONCLUSIONS: 16 immune-associated genes expressions were affected markedly by LWDHW. It will be helpful for understanding the molecular mechanism of LWDHW in ageing.
ABSTRACT
AIM: To construct a recombinant hEGF-hbFGF(78-154aa)fusion protein, which not only has the heparin-binding ability, but also promotes the growth of the cells, and to express the fusion protein in E. coli expression system with high expression level.METHODS: hEGF gene was joined with 231 bp fragment coding hbFGF(78-154aa) and expressed in E. coli. The fusion protein was purified using affinity chromatography of heparin-Hyper D and analyzed with western blot. The pI value and the biological activity were both assayed.RESULTS: The fusion protein was expressed in a high expression level of about 30% of the total cell protein, as estimated by SDS-PAGE. Western analysis results showed that the antigenicity of fusion protein was similar to hEGF. Fusion protein could not only bind heparin but also promote the growth of 3T3 cell. The pI value of fusion protein was 5.2.CONCLUSION: The recombinant hEGF-hbFGF(78-154aa) fusion protein possessed the characteristics of both hEGF and hbFGF. This new-designed protein would become a good object for the research on the relationship between the structure and the function of the growth factor.
ABSTRACT
Objective: To study the antitumor activity and immune modulation of extract from Chlorella pyrenoidosa Chick. (CE). Methods:Cyclophosphamide is positive control and saline is negative control. S180-bearing and HCA-bearing mice were used as animal model. The changes of the growth of S180 and HCA tumor cells in vitro, the changes of tumor weight in vivo and the effect on immune system such as phagocytosis of macrophages,proliferation of lymphocytes were investigated when CE were used. Results: The tumor cells were killed by CE in vitro. CE inhibited tumor growth markedly in S180 and HCA bearing mice and the effect was enhaced if CE and cyclophosphamide were used simultaneously. CE also enhanced the immune function. Conclusion: CE has the antitumor effect and the effect of immune modulation.