Autologous regulatory T cells can suppress the proliferation of lymphoma cell line in vitro / 中国实验血液学杂志

This study was aimed to investigate the suppressive effect of regulatory T (Treg) cells on the T cell lymphoma EL4 cell line and to explore its mechanism. C57BL/6 Mouse Treg cells were isolated by MACS (magnetic cell sorting). The purity and the expression of Foxp3 were detected by flow cytometry. The suppressive effect of sorted Treg cells on EL4 cells was detected by MTT assay. The secretion of TGF-beta1 and IL-10 was examined by enzyme-linked immunosorbent assay (ELISA). The results showed that CD4(+)CD25(+) T cells could be successfully isolated by MACS with the purity reaching 91.6% and the expression level of Foxp3 was 78.9%. The ratio of viable cells was more than 95%. Regulatory T cells could suppress the proliferation of EL4 cells effectively in the presence of antigen presenting cells (APCs). And the suppressive effect was most significant at 1:1 ratio. In addition, the suppression still existed without APCs. TGF-beta1 and IL-10 could not be detected by ELISA. It is concluded that the Treg cells can suppress T lymphoma cell in vitro. The suppressive effect of Treg cells works in dose-dependent manner, but not in cytokine-dependent manner. The mechanism of this suppression may take effect through cell-cell contact.

Analysis of high-frequency stimulation-evoked synaptic plasticity in mouse hippocampal CA1 region / 生理学报

Extracellular recordings of field excitatory postsynaptic potential (fEPSP) is one of the most common ways for studies of synaptic plasticity, such as long-term potentiation (LTP) and paired-pulse plasticity (PPP). The measurement of the changes in the different components of fEPSP waveform, such as the initial slope, initial area, peak amplitude and whole area, were commonly used as criteria for the judgement of potentiation or depression of synaptic plasticity. However, the differences in the conclusions drawn from measuring different components of fEPSP waveform at the same recording have still been largely ignored. Here we compared high-frequency stimulation (HFS)-evoked synaptic plasticity, both LTP and PPP, by measuring different components of fEPSP waveform, including the initial slope, initial area, peak amplitude, whole area and time course. The results not only indicated the acceleration of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor kinetics underlies LTP in hippocampal CA1 region of mice, but also showed that different measurements of fEPSP waveform at the same recording result in different magnitudes of LTP and different forms of PPP in hippocampal CA1 region of mice. After HFS, the paired-pulse ratio was slightly decreased by measurement of the initial area, but obviously increased by measurement of the initial slope of the pair fEPSPs. These results might draw apparently contradictory conclusions. Therefore, careful and complete analysis of the data from different parts of fEPSP waveforms is important for reflection of the faithful changes in synaptic plasticity.

Protective Effects of Diazoxide on Injury of Human Renal Tubular Cell Induced by Serum Obtained from Neonates with Asphyxia / 实用儿科临床杂志

Objective To explore the protective effects of diazoxide on injury of human renal tubular cell(HK-2)induced by serum obtained from neonates with asphyxia.Methods HK-2 cells was used as the target cel1.The attacking concentration of serum obtained from neonates with asphyxia was 200 mL/L.The experiment was designed as 3 groups.HK-2 cells were divided into control group,asphyxia group,and diazoxide group.Control group:joined nutrient fluid including 100 mL/L embryo cow blood serum.Asphyxia group:joined nutrient fluid including the isometric 200 mL/L serum obtained from neonates with asphyxia.Diazoxide group:the diazoxide was joined nutrient including the isometric 200 mL/L serum obtained from neonates with asphyxia fluid.The diazoxide density finally was 100 ?mol/L.Then the change of morphology was observed and photographed under inverted microscope,and the cell viability was measured by methyl thiazolyl tetrazolium method,and the leakage rate oflactate dehydrogenase(LDH)was determined by biochemical methods.Results Under inverted microscopy,HK-2 cells in control group pastes the wall to be good,assumes the paving stone type,into flat polygon,fission many,the cell arrangement was close,connection large expanse,quantity were many.Compared with control group,the HK-2 cell to suffer injury obviously,the shape changed,become the anomalous circular or the ellipse by the model flat polygonal cell,the intercellular space crevice enlarged,the connection was loose,intercellular space obviously many cell fragmented.Living cell quantity reduced obviously,the cell vigor dropped,and the leakage rate of LDH increased significantly in asphyxia group(P