Biomedical subjects

Hong-Gui Xu

Publications and source records attributed to Hong-Gui Xu.

7 recordsLinked to original sources

PubMed2006

[Ex vivo expansion of megakaryocytic progenitors from mobilized human peripheral blood].

This study was aimed to investigate the effect of some culture system composed of various cytokine combinations (TPO, SCF, FL, IL-1, IL-3, IL-6) on ex vivo expansion of megakaryocytic progenitors induced from CD34+ cells of peripheral blood and to seek a optimal cytokine combination and culture time. Mononuclear cells were isolated from mobilized peripheral blood (MPB) by density gradient centrifugation over Ficoll. CD34+ cells were purified by using an immunomagnetic bead separation system. The selected CD34+ cells were seeded in Iscove's modified Kulbecco's medium (IMDM) supplemented with fetal calf serum (FCS) and various kinds of cytokines. After 15 days of culture, the content of CD41+ cells in culture system were determined by flow cytometry, and the number of megakaryocyte colony-forming unit (CFU-MK) was measured simultaneously. The results showed that after definited days of culture, the cytokine combination TPO/FL/IL-6/IL-3 was the most suitable for MPB to obtain high number of MK, and better than any other three groups (P < 0.05). The increase multiple of CD41+ cells was 93.97 +/- 17.27 on day 5 and 131.23 +/- 18.26 on day 10. On day 15, the proportion and the increase multiple of CD41+ cells decreased obviously. The expansion multiples of CFU-MK were 93.33 +/- 10.02 on day 5 and 120.67 +/- 13.01 on day 10, higher than any other groups. It is concluded that TPO/FL/IL-6/IL-3 combination was the best optimal for expansion ex vivo of megakaryocytic progenitors from MPB, and its suitable duration of culture was 10 days; a culture system for expansion ex vivo of megakaryocytic progenitors have been established in this study.

Antigens, CD34↗

PubMed2005

[Construction of pcDNA3.1(+)/A2E eukaryotic expression vector and its expression on K562 cell].

To construct pcDNA3.1(+)/A2E eukaryotic expression vector and obtain a stable expression on HLA-I negative human K562 cell, PCR technique was employed to amplify A2E cDNA from the multi-cistron expression vector pG/A2E carrying HLA-E and HLA-A2 cDNA through internal ribozyme entry site (IRES), the cDNA was subcloned into vector pcDNA3.1(+), thus a eukaryotic expression was constructed and named pcDNA3.1(+)/A2E; then, the recombinant plasmid was transferred into the target cells, followed by screening with G418 and limiting dilution; finally, flow cytometry was adopted to detect HLA-E expression on the target cells. The results showed that HLA-E molecules were successfully expressed on K562 cells transfected with pcDNA3.1(+)/A2E (27.76%) and the expression of HLA-E molecules was not detected on K562 cells transfected with pcDNA3.1(+). It is concluded that the pcDNA 3.1(+)/A2E eukaryotic expression vector was successfully constructed and the HLA-E molecules were expressed on K562 cells. The data presented here would be expected to lay a good basis for the research of the molecular mechanism of HLA-E function and the interaction between HLA-E and the receptor on NK cells, as well as the influence of the expression of HLA-E in vitro on NK cells.

Cloning, Molecular↗

PubMed2005

[Study on the expansion of megakaryocyte progenitors in vitro from cord blood].

This study was aimed to investigate the effect of various cytokines on megakeryocytes expansion in vitro from human cord blood CD34(+) cells in order to establish an optimal culture system for MK expansion. Mononuclear cells were obtained by Ficoll-Hapaque density gradient separation. CD34(+) cells were positively isolated using a CD34 progenitor cell isolation kit. CD34(+) cells were placed into 24 well plates at a concentration of 2 x 10(4) per well. Each well contained 1 ml of IMDM with the present of effective MK cells growth cytokines. Clonogenic potentials of MK progenitor were assayed using a methylcellulose cultures system. The results suggested that four cytokines (IL-3 + IL-6 + TPO + FLT3L) culture system could effectively induce and expand cord blood CD41(+) MK cells. The number of CD41(+) cells expanded 154.67 +/- 32.21-fold on day 7, and 193.23 +/- 25.24-fold on day 14. In conclusion, established expansion system in vitro for MK cells provides experimental foundation for recovery of platelets after cord blood transplantation.

Antigens, CD34↗

PubMed2005

[Clinical observation on needle pricking for treatment of infertility due to varicocele after varicocelectomy].

OBJECTIVE: To observe clinical therapeutic effect of needle pricking therapy on infertility with varicocele after varicocelectomy. METHODS: One hundred and twenty-two cases were randomly divided into a treatment group of 62 cases and a control group of 60 cases. The treatment group were treated with needle pricking at sacral plexus nerve spots and lumbar plexus nerve spots, and the control group were treated with intramuscular injection of HCG. RESULTS: After treatment, the pregnancy rate of the patient's wife was 79.0% in the treatment group and 41.7% in the control group with a significant difference between the two groups (P < 0.01); the production hormones improved significantly in the both groups (P < 0.01); superoxide dismutase and Zn in the semen elevated significantly in the treatment group (P < 0.05). CONCLUSION: Needle pricking therapy can significantly improve and regulate endocrines in the patient of varicocele after varicocelectomy, and elevate quality of semen and sperm and the pregnancy rate of the patient's wife.

Biopsy↗

PubMed2004

[Analysis on HLA-E polymorphism in Guangdong Han population].

To investigate the distribution of HLA-E alleles and linkage between HLA-E and HLA-A or -B loci in Chinese Han in Guangdong area, HLA-E alleles were detected by using PCR-SSP in 150 unrelated healthy individuals from Guangzhou area; HLA-A, -B antigens typing in 106 individuals was carried out with NIH standard microlymphocytoxic method. Analysis of linkage was performed between HLA-E and HLA-A, -B. The results showed that three alleles of HLA-E could be detected in this population. They are E * 0101, E * 01031, E * 01032, with the frequency of 45.33%, 32.33%, 22.33% respectively. No E * 0102 and E * 0104 could be detected in all of these individuals. The analysis of linkage on two loci between HLA-E and HLA-A or -B showed that no significant difference could be found between expected frequencies and observed frequencies except B15/E * 01032 and A2/E * 01032. In conclusion, the high conservative polymorphism of HLA-E suggests that it's biological characteristic is different from that of classical HLA class Ia molecules.

Alleles↗

PubMed2002

[Establishment of a murine model for allogeneic umbilical cord blood transplantation].

This study was undertaken to establish a murine model for unrelated allogeneic umbilical cord blood transplantation (UCBT). The characteristics and percentage of hematopoietic stem/progenitor cells between near-term fetal and neonatal murine peripheral blood (FNPB) and bone marrow (BM) were evaluated by flow cytometry and semisolid methylcellulose culture. BABL/c (H-2(d)) recipient mice conditioned with high dose CTX were transplanted with FNPB form C57BL/6 (H-2(b)) mice and the survival rate, hematopoietic and immunological reconstruction, graft versus host disease (GVHD) and engraftment level were observed. The results showed that the numbers of day 14 CFU-GM and CFU-GEMM in FNPB (176.40 +/- 78.39)% and (141.40 +/- 56.57)%, respectively were much higher than those in BM (75.20 +/- 26.41)% and (68.80 +/- 23.95)%, respectively. Moreover the percentage of Sca-1(+) CD34(+) cell subsets in FNPB (3.63 +/- 1.13)% was also higher than that in BM (1.41 +/- 0.8 7)%. FNPB transplantation improved survival rate and reconstituted hematopoietic and immune function in recipients. There was no evidence of GVHD. Chimeric analysis showed that the proportion of donor cells in BM of recipients was 27.94% at 21 days after transplantation. It was concluded that FNPB contains more hematopoietic stem and progenitor cells with high expansion ability and weak allogeneic immunity, which was similar to human UCB. The murine model for allogeneic UCBT (C57BL/6-->BALB/c) was established successfully.

Animals↗

PubMedDate not supplied

Immunosuppressive treatment of aplastic anemia in Chinese children with antithymocyte globulin and cyclosporine.

Fifty-one children with aplastic anemia (AA) from 1993 to 2004 in the authors' institution were treated by 3 therapies: 11 patients in group 1 received the SSL-6 protocol; 16 patients in group 2 had CsA alone, where the dose of CsA began from 9-12 mg/kg in the initial 2 weeks and tapered off to 5 mg/kg later; 24 patients in group 3 were treated combining rabbit ATG (Pasteur, Merieux) 2.5 mg/kg for 5 days with CsA, which was the same dose as in group 2. The response was 27, 50, and 79%, respectively. The statistical analysis showed that the protocol of intensive immunosuppressive treatment (IST) was the most effective one and CsA was better than that of SSL-6. None of our patients developed clone diseases although the follow-up was as long as more than to 9 years. The data suggest that children with AA should receive IST as first-line therapy in developing countries. Hematopoietic stem cell transplantation (HSCT) is effective treatment for patients with aplastic anemia (AA). However, HSCT is not widely used in China for economic reasons and lack of donors. Immunosuppressive therapy (IST) is now the mainstay treatment for AA. To evaluate the effect of immunosuppressive therapy, combining antithymocyte globulin (ATG) with cyclosporine (CsA), a retrospective study on 51 children with AA from January 1993 to December 2004 treated in the authors' department was performed.

Adolescent↗