Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
Add filters








Language
Year range
1.
Article in Chinese | WPRIM | ID: wpr-248569

ABSTRACT

T cell immunoglobulin mucin (TIM) family playsa key role in regulating immune responses.In this study,the interactions of human TIM family with apoptotic cells were evaluated in order to provide a foundation for further study on the roles of human TIM genes in apoptosis.Nine kinds of pEGFP-N1 eukaryotic expression vectors containing different lengths of the three members of human TIM genes for the expression of TIM-EGFP and the vectors for the expression of TIM-Fc fusion proteins were constructed.It was found that human TIM proteins could recognize and bind to apoptotic cells directly,but not to viable cells.The interactions of sTIM-1-EGFP,sTIM-3-EGFP and sTIM-4-EGFP with apoptotic cells were blocked by TIM-1-Ig,TIM-3-Ig and TIM-4-Ig fusion proteins respectively.In addition,human TIM proteins mediated the recognition of apoptotic cells and bound to apoptotic cells directly via the IgV domains.In conclusion,the TIM family may play a key role in the regulation of apoptosis.Our data also suggest that human TIM proteins probably serve as novel proteins for the detection of the early cellular apoptosis.

2.
Article in Chinese | WPRIM | ID: wpr-341107

ABSTRACT

To investigate the effect of autoimmune regulator(AIRE)on phagocytic clearance of apoptotic cells,a recombinant expression vector containing full-length human AIRE cDNA was transfected into 16HBE cells.After incubation with transfected 16HBE cells,engulfment of apoptotic HL-60 cells induced by camptothecin was detected by myeloperoxidase(MPO)staining.The change in the expression of Rac 1 in transfected 16HBE cells was determined by RT-PCR and Western blotting.The results showed that the phagocytosis percentage of the experimental group,the mock trans-fection group and the negative control group(non-apoptotic cells)was(25.50±3.67)%,(6.25±1.58)%and(1.0±0.67)%,respectively.Moreover,the expressions of Rac 1 mRNA and protein were up-regulated in AIRE-transfected 16HBE cells,suggesting that A1RE may function as a regulator in the phagocytic clearance of apoptotic cells by promoting the expression of Rac 1.

4.
Article in Chinese | WPRIM | ID: wpr-284649

ABSTRACT

Patients with Bloom syndrome (BS) show an immunodeficiency, an enhanced sister chromatid exchanges (SCEs), a strong genetic instability and an increased predisposition to all. In order to investigate the differential expression of BLM protein in hematopoietic tumor cell strains and study the effects of BLM gene on ultraviolet (UV)- or hydroxyurea (HU)-induced apoptosis, Western blot was used to detect the expression of BLM protein in normal human bone marrow mononuclear cells and 4 kinds of hematopoietic tumor cell strains. The 4 kinds of hematopoietic tumor cells were exposed to UV light with a germicidal UV lamp or treated with 2 mmol/L hydroxyurea and the apoptotic rate was detected by using AnnexinV-FITC. The results showed that these tumor cells ex- pressed BLM protein higher than the normal human bone marrow mononuclear cells (P<0.01). In the 4 hematopoietic tumor cells, BLM protein was all specially cleaved in response to UV- or HU-induced apoptosis. The increase of BLM protein expression may play an important role in the evelopment of these tumors, and BLM proteolysis is likely to be a general feature of the apoptotic esponse.

5.
Article in Chinese | WPRIM | ID: wpr-284602

ABSTRACT

In order to investigate peptide mimics of carbohydrate blood group A antigen, a phage display 12-met peptide library was screened with a monoclonal antibody against blood group A antigen, NaM87-1F6. The antibody-binding properties of the selected phage peptides were evaluated by phage ELISA and phage capture assay. The peptides were co-expressed as glutathione S-transferase (GST) fusion proteins. RBC agglutination inhibition assay was performed to assess the natural blood group A antigen-mimicking ability of the fusion proteins. The results showed that seven phage clones selected bound to NaM87-1F6 specifically, among which, 6 clones bore the same peptide sequence, EYWYCGMNRTGC and another harbored a different one QIWYERTLPFrF. The two peptides were successfully expressed at the N terminal of GST protein. Both of the fusion proteins inhibited the RBC agglutination mediated by anti-A serum in a concentration-dependent manner. These results suggested that the fusion proteins based on the selected peptides could mimic the blood group A an- tigen and might be used as anti-A antibody-adsorbing materials when immunoabsorption was applied in ABO incompatible transplantation.

6.
Article in Chinese | WPRIM | ID: wpr-284582

ABSTRACT

The effect of cyclin-dependent kinase inhibitors Cip1/Wafl (p21) on regulatory expression of survivin transcription in human hepatocellular carcinoma cell HepG2 was observed and the related mechanisms explored. Doxorubicin (DOX) was used to treat HepG2. Eukaryotic vector pEGFP-C2-p21 was transfected into HepG2 by lipofectamine and positive clones were screened out by G418. The mRNA expression of p21 and survivin was detected by real-time fluorescent quantitative polymerase chain reaction (RQ-PCR). Flow cytometry was used to examine the cell cycle, and reverse transcription polymerase chain reaction (RT-PCR) was used to measure the levels of E2F-1 and p300. The results showed that: (1) After treatment with DOX, the expression of p21 was increased, whereas that of survivin was reduced during 24h of treatment; (2) After transfection of pEGFP-C2-p21 into HepG2, p21 level was significantly enhanced to 2100.11-folds or 980.89-folds in comparison to HepG2 or HepG2-C2 group, and survivin level was markedly down-regulated to 0.54% or 0.59% relative to the control groups; (3) Overexpressed p21 resulted in G1/G0 phase arrest (F=31.59,P<0.01), meanwhile E2F-1 mRNA and p300 mRNA were reduced as compared with those of controls (FE2F-1=125.28,P<0.05;Fp300=46.01,P<0.01). It was suggested that p21 could be a potential mediator of survivin suppression at transcription level in HepG2 cell, which might be through the block at G1/G0 phase and down-regulation of transcription factors E2F-1 and p300.

7.
Article in Chinese | WPRIM | ID: wpr-260138

ABSTRACT

To investigate the distribution characteristics and linkage disequilibrium of T cell immunoglobulin domain and mucin domain protein 4 (TIM4) promoter polymorphisms in asthma patients of Chinese Han population, the promoter region of TIM4 was re-sequenced by PCR-sequencing,and linkage disequilibrium was analyzed by SHEsis software. Four single nucleotide polymorphisms (SNPs) in the promoter region of TIM4 were detected, including two new SNPs (at positions-1609, -153) and two reported SNPs (rs6874202, rs6882076). The frequency distribution of rs6882076 was different among different races (P<0.05). In addition, linkage disequilibrium among the SNPs of the promoter region of TIM4 was found and GGTG was the predominant haplotype.There were four SNPs in the promoter region of TIM4 in asthma patients of Chinese Han population,which were in linkage disequilibrium.

SELECTION OF CITATIONS
SEARCH DETAIL