Objective:To investigate if CD4~+CD25~+ regrating T cells can suppress GVHD mediated by CD4~+ T cells in murine semi-allogeneic bone marrow transplantation model and try to figure out the mechanisms evolved.Methods:C3H(H-2~k) as donors, C3H?B6(H-2~ k/b) F1(recipients) were lethally irradiated and reconstituted with antibody T cell depleted bone marrow(ATBM), and divided into 4 groups: (A)No further treatment(n=10);(B)Infused 5?10~5 C3H CD4~+T cells(CD4,n=10);(C)Infused 5?10~5 CD4~+CD25~+Treg(CD25,n=5);(D)Infused 5?10~5 CD4~+T cells plus 5?10~5 CD4~+CD25~+Treg(CD4/CD25,n=6).Results:All mice in ATBM group, CD25 group and CD4/CD25 groups survived until 60 days without any GVHD symptoms, while all mice in CD4 group died in 10 days from GVHD.Conclusion:CD4~+CD25~+Treg cells did not cause GVHD and can prevent GVHD mediated by CD4~+ T cells while co-injected with CD4~+ T cells.

Objective To study the mobilizing effect induced by low dose irradiation on mouse peripheral blood(stem/progenitor) cells.Methods Peripheral blood CFU-GM was cultivated in methylcellulose semi-solid culture system,and c-kit~+cells were counted by flow cytometry after low dose irradiation or combined with G-CSF.(Results The) CFU-GM and c-kit~+ cells of peripheral blood in irradiated mice were much higher than those in control mice,the CFU-GM started to increase at 24 h after irradiation,reached maximum at 72 h and stayed high level till 96 h.The CFU-GM and c-kit~+cells at 72 h after 75 mGy irradiation were the most.The CFU-GM and c-kit~+cells in semi-dose G-CSF+75 mGy group were much higher than those in simple low dose irradiation group and were close to those in the group dealed with adequate G-CSF.Conclusion Low dose irradiation can mobilize peripheral blood stem/progenitor cells,and low dose irradiation combined with G-CSF can produce synergetic effect.

Objective To investigate the inhibitory effect of sodium phenylbutyrate(SPB) combined with gefitinib on NB4 cells.Methods The NB4 cells were divided into 8 groups randomly:control group,PMA group,H-7 group,SPB+PMA group,gefitinib group,gefitinib+PMA group,SPB+gefitinib group.The inhibitory rate of medicine was detected by MTT,the apoptosis of NB4 cells was detected by flow cytometry,the expressions of PKC,CDK,and P53 were detected with Western blotting method.Results The NB4 cells were suppressed obviously.The rate of growth inhibition and proliferation index in SPB+gefitinib group were 92.8% and 5.96%,those in SPB group were 45.1% and 29.6%,and gefitinib group were 61.0% and 35.9%,the differences were significant(P

Objective To study the expression of N-myc downstream regulated gene 1 (NDRG1) in renal cell carcinoma and its relationship with microvessel density (MVD) and clinicopathologic parameters.Methods Immunohistochemical study for NDRG1 and CD34 was performed on paraffin sections of cases of renal cell carcinoma and adjacent non-neoplastic renal parenchymal tissue. MVD was analyzed by CD34immunostaining.Results Immunohistochemical study showed that non-neoplastic proximal convoluted tubule, distal convoluted tubule and collecting ducts was positive for NDRG1 (membranous and cytoplasmic). The expression rate of NDRG1 in renal cell cancer was 51%, which was significantly lower than that in normal renal tissues of 100 % (P ＜0.05).Clinicpathologically, the result also showed a close relation between lower NDRG1 expression and higher pathologic grade (χ2 =9.968, P =0.007), later clinic stage (χ2= 6.437,P =0.011), lymph node metastases (χ2=5.800, P =0.016) and higher MVD of cancer (t =2.235, P =0.030)whereas no relation with other factors. Conclusion NDRG1 might play as a cancer suppressor gene in renal cell carcinoma in that it could be correlated with tumor invasion and metastasis.It might also suppress tumor growth and metastasis by regulation of tumor angiogenesis.

0.05).There were better effect of removal of myelin(P2

0.05);While the differences of the levels of p53,Bcl2,Bax between all D_1+D_2 groups and sham-irradiated group were significant(P

AIM: Nur77 expression can lead to T cell apoptosis, and it is activated by the second messenger calcium. The calcium-responsive elements in the Nur77 promoter are two putative binding sites for the transcription factor, myocyte enhancer factor-2D (MEF2D). In this study, we explored whether MEF2D could be acetylated in Nur77-induced T cell apoptosis and whether MEF2D acetylation was affected by the regulation of Nur77 expression. METHODS: The experiment was performed at Department of Hematology-Oncology in the First Hospital of Jilin University from November 2006 to September 2007. ①Escherichia coli DH5?and plasmid pcDNA3 were held by the Research Center in the First Hospital of Jilin University. Plasmids pET32M, Flag-p300 and pSilencerTM-p300 RNAi were gifts from Professor Zhengguo Wu from Hong Kong University of Science and Technology. Plasmid NFATp was contributed by Yun Chen from Harvard University. Jurkat cells were provided by Department of Hematology- Oncology in the First Hospital of Jilin University. ②The full-length Nur77 gene, generated by PCR, and the Nur77-dependent luciferase reporter gene were subcloned into plasmid pcDNA. The variant sequences of MEF2D (1-514, 1-121, 1-300, 301-514) and the MEF2D (4KR) lysine-to-arginine mutants, at lysine sites K245/K250/K267/K279, had the Flag epitope at their amino termini. All of the above plasmids were constructed in bacterial expression vectors and the constructed clones were verified by sequencing and then transfected with liposome DMRIE-C. ③The impact of p300 on the trans-activation function of Nur77, mediated by MEF2D, was detected by luciferase reporter assays after Nur77-dependent reporter gene was transfected together with MEF2D, p300 or NFATp into Jurkat cells. In vivo acetylation of endogenous MEF2D and whether acetylation of MEF2D was affected by blocking the expression of p300 were detected by immunoprecipitation. The acetylated sites of MEF2D were detected by acetylation assays in vitro. The impacts of both MEF2D acetylation defects on trans-activation of Nur77 and on apoptosis of T cells induced by Nur77 were detected by luciferase reporter assays and flow cytometry, respectively. RESULTS: ①Although the dimeric complex of MEF2D and NFATp could not induce the transcription of Nur77, significant transcription was achieved with the ternary complex of p300, NFAT and MEF2D. The dimeric complex of p300 and MEF2D could also significantly induce Nur77transcription.②MEF2D was acetylated after the calcium signaling pathway was activated by PMA/Iono. The acetylation level of MEF2D was markedly reduced when p300 expression was blocked by p300 RNAi. ③The simultaneous mutation of K245/K250/K267/K279 lysine sites largely prevented the acetylation of MEF2D, which demonstrated that K245/K250/K267/K279 lysine sites in vitro were the major sites of MEF2D acetylation. ④The MEF2D acetylation defect increased by 2.48 fold the transcription f of Nur77, when compared with vacant vector. But compared with wild type MEF2D, transcription of Nur77 was decreased by 70.4%. ⑤When compared with vacant vector, Nur77 expression could increase total T cell apoptosis of early and late periods from 4.3% up to 16.3%; the co-expression of wild type MEF2D and Nur77 could further increase total T cells apoptosis of early and late periods from 16.3% to 31.0%. However, the co-expression of acetylation defective MEF2D mutant and Nur77 significantly decreased total T cells apoptosis of early and late periods from 16.3% to 9.2%. CONCLUSION : p300 has a major impact on the transactivation function of Nur77 mediated by MEF2D. MEF2D could be acetylated in Nur77-induced T cell apoptosis and acetylated MEF2D could promote T cell apoptosis by upregulating the transcription function of Nur77.

Objective:To observe the effects of sodium butyrate on the expression of CD86 molecule on acute leukemia cells and explore the mechanisms of action.Methods:The expression of CD86 in NB4,HL-60 and U937 treated by SB or not was assayed by flow cytometric analysis.The alteration of CD86 mRNA was examined by semiquantitative RT-PCR.AUT gel electrophoresis was applied to check the state of histone acetylation.The content of phospho-CREB was assayed by pCREB kit.Results:Up-regulation of CD86 was observed on those cells treated by SB.The levels of CD86 mRNA in SB treated cells were statistically enhanced.The acetylation degrees of SB treated cells were higher than control groups.The contents of phospho-CREB were also raised in SB treated cells.Conclusion:SB can improve the acetylation states of acute leukemia cells,remodel the chromatin which contributes to the binding on DNA of transcription factors,such as CREB and then promote the transcription and expression of CD86.

: The management of peripheral nerve injury is a tough problem clinically.Intensive studies in the past were focused on the bridging of nerve defects and the improvement of regeneration rate.But actually the clinical results of functional recovery after peripheral nerve lesion is mainly decided by the accurate regeneration of axons to their original target tissues and structures.Therefore,better clinical results could be obtained by a greater understanding of the cellular and molecular biology of selective nerve regeneration and the application of this theory clinically.This paper summarized recent studies on the cellular and molecular biology mechanisms of peripheral nerve selective regeneration.

Objective To explore laboratory diagnosis tests for lupus anticoagulant associated by coagulation factors(F Ⅷ,F Ⅸ and F Ⅺ)deficiency.Methods We investigated the coagulation factors'activity,coagulation factors'antibodies,anticardiolipin antibodies,lupus anticoagulant and thrombin generation in thirteen patients of lupus anticoagulant associated by coagulation factors(F Ⅷ,F Ⅸ and F Ⅺ)deficiency,ten hemophilia A patients, forty-eight healthy people. In these thirteen patients,there were five patients with schizophrenia and had been taking chlorderazin for a long time,two patients with antiphospholipid syndrome, one patient with pemphigus, five patients in which causes of disease were unknown.Among these patients,two patients has haemorrhage,eleven patients don't have reduced.The antibodies of these coagulation factors and LA were positive.Six patients in this group were ACA poslhve,and seven patients were ACA negative.The lag time of eleven non-haemorrage patients with LA positive associated by F Ⅷ,F Ⅸ and F Ⅺ deficiency was(5.60±1.18)min,higher than that of control group which was(1.88±0.25)min.This differenee had statistically significant(t=10.05,P＜0.01).The time to peak was(8.11±1.91)min,significantly higher than that of control group which was (4.10±0.36)min(t=8.83,P＜0.01).The endogenous thrombin potential(ETP)was(1 640.87±higher than that of hemophilia A patients which was(38.50±6.20)%(t=9.77,P＜0.01).The time to peak of hemophilia A patients was(8.01±1.81)min,significantly higher than that of control group which Was(4.10±0.36)min(t=8.20,P＜0.01).The lag time of control group and hemophilia A patients was (1.88±0.25)min and(2.01±0.84)min,respectively.There was no significant difierence of the lag time between these two groups(t=1.26,P＞0.05).Conclusions Diseases like lupus anticoagulant associated bv coagulation factors(F Ⅷ,F Ⅸ and F Ⅺ)deficiency and inherited hemophilia should use APTT,PT,should be used as confirmation tests. LA and ACA may serve as indication test for identifying the causes of these diseases. ETP and ETP percentage are quite good parametem for predicting the bleeding risk of patients with LA positive associated by coagulation factors(F Ⅷ,F Ⅸ and F Ⅺ)deficiency.