Effects of decitabine on proliferation and apoptosis of NB4 and K562 cells / 中国实验血液学杂志

This study was aimed to investigate the effects of decitabine (DAC) on proliferation and apoptosis of leukemia NB4 and K562 cells. The proliferation inhibition of DAC on NB4 and K562 cells was detected by Trypan blue staining. After treatment of DAC at different concentrations, the changes of cell cycle and CD11b expression was determined by flow cytometry. The cell morphological changes were observed by Wright's staining. The DNA ladder was used to detect cell apoptosis. The results indicated that DAC significantly inhibited the proliferation of NB4 and K562 cells in dose-and time-dependent manner. The median inhibitory concentration (IC50) of DAC-treated NB4 and K562 cells for 72 h was 0.113 µmol/L and 0.138 µmol/L, respectively. After treating these two cell lines with DAC at different concentration for 72 h, the cell ratio in G0/G1 phase significantly increased, while the cell ratio in S phase obviously decreased in 0.15 µmol/L DAC group (P < 0.05). The expression levels of myeloid differentiation antigen CD11b of both cell lines significantly increased in contrast to the control group (P < 0.05). The cell morphology detected by Wright's staining displayed partial differentiation and apoptosis after treating NB4 and K562 cells with DAC for 48 h. Typical apoptotic DNA ladder was observed in 0.15 µmol/L DAC group at 48 h. It is concluded that DAC can inhibit NB4 and K562 cell proliferation, induce cell differentiation and apoptosis, but more obviously for NB4 cells.

Differential proteomic analysis in human umbilical cord mesenchymal stem cells induced by cobalt chloride / 中华血液学杂志

<p><b>OBJECTIVE</b>To analyze the differential proteomics in human umbilical cord mesenchymal stem cells (MSC) induced by chemical hypoxia-mimetic agent cobalt chloride (CoCl(2)) by two-dimensional gel electrophoresis (2-DE) and mass-spectrometry.</p><p><b>METHODS</b>2-DE was performed to separate proteins from treated and untreated human umbilical cord MSC with CoCl(2). 2-DE images were analyzed by ImageMaster 2D Platinum software 6.0. The differential expressed proteins was identified by MALDI-TOF-MS. The differential proteins were classified based on their functions.</p><p><b>RESULTS</b>2-DE reference patterns of CoCl(2) treated human umbilical cord MSC were established. A total of twenty-six differential proteins were identified, of them eleven proteins were up-regulated and fifteen down-regulated. Their biological functions involved in carbohydrate metabolism, protein metabolism and modification, lipid metabolism, coenzyme and prosthetic group metabolism, cell cycle, immunity and defense, cell structure and motility, signal transduction, protein targeting and localization, neuronal activities, muscle contraction, etc. Peroxiredoxin1 (Prdx) was down-regulated, whereas alpha-enolase (ENO1) and vesicle amine transport protein 1 homolog (VAT1) up-regulated.</p><p><b>CONCLUSION</b>The effects of hypoxia on human umbilical cord MSC were participated by multiple proteins and involved in multiple functional pathways.</p>

p38 mitogen-activated protein kinase inhibitor suppresses the expression of pro-inflammatory cytokines in liver from brain dead rats / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To observe the suppressive effect on the expression of pro-inflammatory cytokines in liver from brain dead (BD) rats through inhibition of p38 mitogen-activated protein kinase (MAPK) signaling pathway by SB203580.</p><p><b>METHODS</b>A total of 30 male Wistar rats weighing from 180 to 200 g were randomly divided into 3 experimental groups: (1) BD group (n = 10): brain death was induced in rats; (2) BD+SB203580 group (n = 10): brain death was successfully induced and SB203580 (10 mg/kg) was given through dorsal vein of penis. After brain death artificial ventilation was maintained for 6 hours and only those with mean arterial blood pressure more than 80 mm Hg (1 mm Hg = 0.133 kPa) were accepted as BD donors. (3) Control group (n = 10): living healthy rats. The expressions of TNFalpha and IL-1beta mRNA in liver tissues were analyzed by RT-PCR and the protein expressions of TNFalpha, IL-1beta and phosphorylated p38MAPK were detected by Western blot.</p><p><b>RESULTS</b>The phosphorylated p38MAPK detected in the liver in BD group was significantly increased compared with the control group (q = 172.53, P < 0.01), and the expressions of TNFalpha and IL-1beta mRNA and proteins in liver were also significantly increased in BD group compared with the control group (q = 123.99, 135.35, 243.09 and 192.23, respectively, P < 0.01). The phosphorylated p38MAPK was decreased in BD+SB203580 group and significantly decreased compared with the BD group (q = 63.90, P is less than 0.05), but higher than that in control group (q = 108.63, P < 0.01). The expressions of TNFalpha and IL-1beta mRNA and proteins in liver were significantly decreased in BD+SB203580 group compared with the BD group (q = 55.11, 98.13, 61.03 and 50.85, respectively, P < 0.01), but higher than that in control group (q = 68.89, 37.22, 182.06 and 141.38, respectively, P < 0.01). SB203580 can suppress the expression of pro-inflammatory cytokines in the liver of brain dead rats through the inhibition of p38MAPK signaling pathway which may reduce the immunogenicity of donor livers.</p>

Study on clonal proliferation of TCR Vbeta subfamily T cells induced by AML-M(2a) cells in vivo and in vitro / 中国实验血液学杂志

To observe the expression and clonal expansion of TCR Vbeta subfamily T cells induced by AML-M(2a) cells in vivo and in vitro, complementary determining region 3 (CDR3) of TCR beta with variable region genes was amplified by using RT-PCR in both peripheral blood mononuclear cells (PBMNC) and T cells from mixed lymphocyte and tumor culture (MLTC) from four AML-M(2a) patients. The positive products were further analyzed to identify the clonality of T cells by genescan. The results showed that the similarity distribution of TCR Vbeta subfamily T cells was found Vbeta in PBMNC and MLTC. One or two clonality expansions of T cells could be found in predominant TCR Vbeta subfamily T cells induced by A ML-M2a cells from 3 cases in vivo and in vitro. It was concluded that clonal expansion of TCR Vbeta subfamily T cells stimulated selectively by AML-M(2a) cells may be a specific immune response of patient's T cells to AML-M(2a) cells associated antigen. The clonal proliferation of TCR Vbeta subfamily T cells were affected somewhat by environmental difference in vivo and in vitro.