Evaluation of subclinical left ventricular myocardial systolic dysfunction in type 2 diabetes mellitus patients with and without diabetes peripheral neuropathy by global myocardial work.

AIMS: Speckle-tracking echocardiography can non-invasively estimate myocardial work (MW) to evaluate left ventricular (LV) myocardial systolic function. The present study evaluated whether MW may detect subclinical LV myocardial systolic dysfunction in type 2 diabetes mellitus (T2DM) patients with and without diabetes peripheral neuropathy (DPN). METHODS: A total of 127 T2DM patients were included in the present study, including 67 T2DM patients with DPN. In addition, 73 sex- and age- matched healthy individuals served as normal controls. The global myocardial work index (GWI), global constructive work (GCW), global waste work (GWW), global positive work (GPW), global negative work (GNW), global work efficiency (GWE) and GCW/GWW were measured and analysed. Furthermore, the differences in MW parameters among normal controls, T2DM patients, and T2DM patients with DPN were analysed. Multiple regression models were built to explore for the independent influencing factors of GWI and GPW values in T2DM patients with DPN. Receiver operating characteristic curve analysis was performed to evaluate the sensitivity and specificity of MW in evaluating subclinical LV myocardial systolic dysfunction in T2DM patients with DPN. RESULTS: The GWI, GCW and GPW of T2DM patients with DPN were significantly decreased compared with those of T2DM patients and normal controls (P < 0.001) and showed a significant decreasing trend overall (P trend < 0.001). GWE and GCW/GWW were significantly decreased in T2DM patients with DPN compared with normal controls (P < 0.05). Although GWW was not significantly different among the three groups, it showed an increasing trend (Ptrend = 0.033). High-density lipoprotein cholesterol (HDL-C) levels were independent influencing factor for decreased GWI (ß = 0.21, P = 0.031) and GPW (ß = 0.19, P = 0.043) values in T2DM patients with DPN. The combination of the GWI, GCW, GWE, GPW and GCW /GWW had good sensitivity (62.69%) and specificity (89.04%) when evaluating subclinical LV myocardial systolic dysfunction in T2DM patients with DPN. CONCLUSIONS: Non-invasive evaluation of LV myocardial work can detect subclinical LV myocardial systolic dysfunction in T2DM patients with and without DPN. DPN has additive deleterious effects on LV myocardial systolic function in T2DM patients. The reduction of HDL-C levels may indicate the occurrence of subclinical LV myocardial systolic dysfunction in T2DM patients with DPN.

Diagnosis, treatment and genetic analysis of a case of Alstrom syndrome caused by compoud heterozygous mutation of ALMS1.

Alstrom syndrome is a rare autosomal recessive disorder disease caused by mutations in the ALMS1 gene, and its typical clinical manifestations include cone-rod retinal dystrophy, sensorineural deafness, obesity, insulin resistance, diabetes mellitus, hypertriglyceridemia, non-alcoholic fatty liver, dilated cardiomyopathy, and progressive hepatic and renal dysfunction. In this report, we followed up a young male patient presenting with diabetes mellitus, who was later diagnosed with blindness, deafness, hyperlipidemia, obesity, fatty liver, and insulin resistance. Genetic testing revealed a compound heterozygous mutation in ALMS1 from the patient, with an exon 8 c.5535delG (p.S1847Lfs*24) mutation inherited from the maternal side and an exon 16 c.10819C>T (p.R3607X) mutation from the paternal side. Neither of these two mutations had been previously recorded in the known ALMS1 genetic mutation database. Hyperinsulinemic-euglycemic clamp test indicated that the insulin sensitivity index was significantly improved in the patient after taking oral dapagliflozin. By summarizing and analyzing this case, we should consider Alstrom syndrome in clinical adolescent-onset diabetes patients with blindness, deafness, severe insulin resistance, and lipid metabolism disorder. These two new mutation sites identified in this case enrich the genetic mutation database of the ALMS1 gene, and the follow-up data of this study provide new evidence for deciding appropriate glucose-lowering regimens in patients with Alstrom syndrome.

ClC-5 alleviates renal fibrosis in unilateral ureteral obstruction mice.

Renal fibrosis is the major feature of end-stage renal disease with high mortality. Chloride (Cl-) moving along Cl- channels has been suggested to play to an important role in renal function. This study aims to investigate the role of ClC-5 in renal fibrosis in unilateral ureteral occlusion (UUO) mice. C57BL/6 mice received UUO surgery followed by delivery of adeno-associated virus encoding ClC-5 cDNA (AAVClC-5). Western blotting, real-time PCR and histological analysis were used to investigate the effects of ClC-5 on renal fibrosis and underlying mechanisms. The expression of ClC-5 was significantly decreased in renal cortex of UUO mice and transforming growth factor-ß1 (TGF-ß1)-stimulated HK2 cells. Overexpression of ClC-5 in vivo markedly ameliorated UUO-induced renal injury and fibrosis. The increased expressions of plasminogen activator inhibitor type 1, connective tissue growth factor, collagen III and collagen IV were also inhibited by ClC-5 upregulation. Moreover, UUO-induced immune cell infiltration and inflammatory cytokines release were attenuated in mice infected with AAVClC-5. In addition, the in vivo and in vitro results showed that ClC-5 overexpression prevented epithelial-to-mesenchymal transition (EMT), concomitantly with a restoration of E-cadherin expression and a decrease of vimentin, α-SMA and S100A4 expressions. Furthermore, ClC-5 overexpression inhibited UUO- or TGF-ß1-induced increase in nuclear factor kappa B (NF-κB) acetylation and matrix metalloproteinases-9 (MMP-9) expression. However, downregulation of ClC-5 in HK2 cells further potentiated TGF-ß1-induced EMT and increase in NF-κB acetylation and MMP-9 expression. ClC-5 upregulation ameliorates renal fibrosis via inhibiting NF-κB/MMP-9 pathway signaling activation, suggesting that ClC-5 may be a novel therapeutic target for treating renal fibrosis and chronic kidney disease.

[Chemical Compositions and Source Apportionment of Road Dust in Yuncheng].

Samples of particulate sources in Yuncheng including road dust, salt lake dust, coal dust, soil dust, construction,cement dust and vehicle exhaust dust were collected. Elements, ions and carbon species in particulate sources samples were analyzed. Enrichment factors and potential ecological risk assessment were used to analyze the characteristics of road dust, and chemical mass balance model was applied to identify the source of road dust. The results showed that, compared with other cities, the proportions of Na(12.1970%) and SO42-(8.5971%) were relatively high while that of Si(9.1123%) was low in road dust in Yuncheng, and enrichment factors showed that the sources of Pb, Cu, Cr, V, As, Ni, Na and Zn in road dust were obviously influenced by human activities; the potential ecological risk of heavy metals in road dust was high, which was affected by anthropogenic sources such as industrial production, the combustion of fossil fuels and vehicle exhaust; the profiles of coal dust, vehicle exhaust dust, construction and cement dust were similar to those of other cities, the Na and SO42- concentrations in soil dust were relatively high, and the proportions of Na and SO42- in salt lake dust were 30.3% and 22.7% respectively; salt lake dust was the largest contributor (53%) to road dust, followed by the soil dust (21%), vehicle exhaust dust (8%), construction and cement dust (7%), and coal dust (5%).

[Pollution characteristics of organic and elemental carbon in PM2.5 in Taiyuan].

PM2.5 samples were collected at four sampling sites to study pollution characteristics of carbonaceous aerosols in Taiyuan during winter and summer. Organic carbon (OC) and elemental carbon (EC) in PM2.5 were analyzed by carbon analyzer, and the characteristics including pollution levels, temporal and spatial distributions of OC and EC, secondary organic carbon (SOC) and relationships of OC and EC were discussed in detail. The average concentrations of OC and EC in winter were 22.3 µg x m(-3) and 18.3 µg x m(-3), respectively, while in summer were 13.1 µg x m(-3) and 9.8 µg x m(-3), respectively. The concentrations of total carbon aerosol (TCA) accounted for 56.6% of PM2.5 in winter, and 36.5% in summer; the concentrations of OC and EC at four sites in winter were higher than those in summer, OC and EC levels showed a good uniformity in winter while in summer, the spatial distributions of OC and EC were obviously different; SOC levels were lighter than other cities; the correlation between OC and EC was stronger in winter than that in summer.

[Characteristics of organic carbon and elemental carbon in PM2.5 in Shuozhou City].

PM2.5 samples were collected at four sampling sites in Shuozhou during the heating and non-heating periods. Organic carbon (OC) and elemental carbon (EC) in PM2.5 were analyzed by Elementar Analysensysteme GmbH vario EL cube and the concentration, spatial and temporal distribution characteristics and main sources of OC and EC were studied. The results were as following: average concentrations of OC and EC in PM2.5 during non-heating period were (14.3 ± 2.7) µg x m(-3) and (10.3 ± 3.1) µg x m(-3) while (23.3 ± 5.9) µg xm(-3) and (20.0 ± 5.7) µg x m(-3) during heating period. The concentrations of OC and EC at four sites during the heating period were higher than those during the non-heating period. The concentrations of OC and EC at SW site during heating were the highest which were 28.5 µg x m(-3) and 28.1 µg x m(-3) while the concentrations at PS sites during non-heating period were the highest, which were 17.7 µg x m(-3) and 14.1 µg x m(-3). The ratios between OC and EC during the heating and non-heating period were all below 2 and the correlation between OC and EC was not good with R2 of 0. 66 during heating period and 0.52 during non-heating period which indicated that sources of carbon aerosols were complex. Carbonaceous aerosol pollution should be reduced by controlling the primary emissions such as coal combustion, vehicle exhaust and biomass burning, and by paying attention to secondary pollution at the same time to improve the air quality in Shuozhou City. The concentrations of SOC during heating and non-heating period were (6.44 ± 2.77) µg x m(-3) and (4.11 ± 1.92) µg x m(-3).

[Characterization of organic and elemental carbon in PM10 in Xinzhou City].

PM10 samples were collected at four sampling sites to study pollution characteristics of carbonaceous aerosols in Xinzhou during heating period (March) and non-heating period (July), 2011. Organic carbon (OC) and elemental carbon (EC) in PM10 were analyzed by Elementar Analysensysteme GmbH vario EL cube, and the characteristics including pollution levels, temporal and spatial distributions of OC and EC as well as OC/EC ratios were investigated in detail. The results were as following: OC and EC mass concentrations of PM10 in Xinzhou were (18.5 +/- 4.5) microg x m(-3) and (16.1 +/- 4.3) microg x m(-3), respectively. The concentrations of total carbon aerosol (TCA) accounted for 70.7% of PM10 during the heating period, and 43.8% during the non-heating period. The concentrations of OC at four sites during the heating period were higher than those during the non-heating period, and this trend was consistent with that of EC concentrations except for SQ site, which indicated coal combustion was a dominant source of OC and EC during the heating period. OC concentration at XT site and EC concentration at DC site were the highest, which were 24.1 microg x m(-3) and 22.0 microg x m(-3) respectively, while the concentrations of OC and EC at SQ site were both the lowest, which were 17.2 microg x m(-3) and 14.5 microg x m(-3), respectively, which indicated that the spatial distributions of OC and EC were obviously different. The average values of OC/EC ratios were all below 2, which indicated that the primary pollution was predominant. The correlation between OC and EC during the non-heating period was good with R2 of 0.55, indicating the emission sources were consistent and the vehicle exhaust played an important role, while the correlation was weak during the heating period (R2 = 0.13), which revealed that the emission sources of OC and EC were complicated. Carbonaceous aerosol pollution should be reduced by controlling the primary emissions such as coal combustion, vehicle exhaust, biomass burning and other industrial sources to improve the air quality in Xinzhou City.

[Characteristic of elements in PM2.5 and health risk assessment of heavy metals during heating season in Taiyuan].

The fine particulate matter (PM2.5) sampled during heating season in Taiyuan city and nineteen samples were used to investigate elemental concentrations and its source potential ecological risks of heavy metals, and to assess human exposure and health risk. The result indicated that main elements were Si, Ca, Al, Na, Mg, K, Fe in PM2.5. The main sources of elements in PM2.5 were divided into five categories including soil dust (43.46%), coal burning (15.69%), vehicle emission (13.41%), industrial dust (9.89%) and the construction cement dust (9.03%). Moreover, the order of potential ecological risk index of heavy metals in PM2.5 was Cd > Ni > Hg > Pb > Cu > Zn > As > Co > Cr > Mn, and the ecological hazards were high. The main exposure of heavy metals in atmosphere was respiratory inhalation . The exposure quantity for children was significantly higher than that for adult. The hazard index values suggested a potential non-carcinogenic risk in PM2.5.

[Distribution and source apportionment of n-alkanes in atmospheric particle in Taiyuan, China].

The n-alkanes in PM10 and typical emission sources samples collected during heating and non-heating periods in Taiyuan were determined with GC-MS. Meanwhile, the distribution characteristics and source identification of n-alkanes were investigated with diagnostic parameters and principal component analysis (PCA). Concentrations of n-alkanes ranged from 213.74 to 573.32 ng.m-3 and 22.69 to 150.82 ng.m-3 in the heating and non-heating seasons, respectively. The n-alkanes concentrations in suburban districts including JY, JCP, XD and SL were higher than those in urban sites in the heating quarter, and the relative concentration in JS was 7 times higher than that in SL in the other period. The correlation of the total n-alkanes in PM10 with that derived from fossil fuel was higher than the correlation with those from plant in the heating quarter, while the opposite result was detected in the other period, manifesting higher contribution of fossil fuel in the heating days. CPI and % WNA values showed that the contribution from plant wax in the non-heating period was higher than that in the heating period, and the alkanes production rate was elevated along with the increase in environmental pressures. Information on higher organic matter maturity was obtained during the heating period by Cmax and OEP and the existence of UCM bulge confirmed that vehicles were the significant contributor to n-alkanes concentration during the whole year. PCA analysis indicated the major component was the mixture of vehicle emission and higher plant, accounting for 51.28% of the total variances, followed by coal dust, accounting for 43. 14%. Cooperating control of emissions from coal combustions and vehicles would be the effective way to lower the concentrations of the corresponding n-alkanes.

[Aerosol size distribution of organic carbon and elemental carbon on the top of coke oven and in the plant area].

In order to investigate the characteristic of organic carbon (OC) and elemental carbon (EC) in particles on the top of coke oven and in the plant area, the particle matter samples of five size fraction including < or = 1.4 microm, 1.4-2.1 microm, 2.1-4.2 microm, 4.2-10.2 microm and > or = 10.2 microm were collected using Staplex234 cascade impactor, and OC and EC were analyzed by Elementar Analysensysteme GmbH vario EL cube. The mass concentrations of OC and EC associated with TSP on the top of coke oven were 291.6 microg x m(-3) and 255.1 microg x m(-3), while those in the plant area were 377.8 microg x m(-3) and 151.7 microg x m(-3). The mass concentration of secondary organic carbon (SOC) in particles with size of < or = 1.4 microm was 147.3 microg x m(-3) in the plant area. The value of OC/EC in particles less than 2.1 microm was 1.3 on the top of coke oven. The mass concentration of EC in TSP in the plant area was lower than that on the top of coke oven, while the mass concentration of OC in the plant area was significantly higher than that on the top of coke oven. The mass concentrations of OC and EC associated with particles less than 10.2 microm in the plant area were far higher than those in the atmosphere of area where the coke plant is located. The OC and EC in particles, which were collected both on the top of coke oven and in the plant area, were mainly enriched in fine particles. The size distribution of OC showed a clear distinction between the coke oven top and the plant area, which revealed that OC in the plant area was more preferably enriched in fine particles than that on the top of coke oven, and the same size distribution of EC was found on the top of coke oven and in the plant area. In the plant area, the mass concentration of SOC and the contribution of SOC to OC increased with the decreasing diameter in particles with diameter of less than 10.2 microm.

[Characterization of PAHs in fly ashes from coke production].

In order to investigate the characteristics of polycyclic aromatic hydrocarbons (PAHs) in ashes from coking, PAHs in ashes from three coke production plants were analyzed with GC-MS, and the distribution characteristics of PAHs and potential toxicity risk were discussed. The sum of 16 EPA prior PAHs varied from 8.17 x 10(2) to 5.17 x 10(3) microg x g(-1). PAH contents from the coke oven (stamp charging) with the height of 3.2 m were two times higher than those from the one (top charging) with the height of 6.0 m, and PAHs in ashes from coal charging were significantly higher than those from coke pushing in the same plant. Four-ring and five-ring PAHs were the dominant species in ashes from coking and the sum of them accounted for more than 80.00% of total PAHs. Chrysene (Chr), benzo [a] anthracene (BaA) and benzo [b] fluoranthene (BbF) were abundant in all ash samples. The content of total BaP-based toxic equivalency (BaPeq) ranged from 1.64 x 10(2) to 9.57 x 10(2) microg x g(-1). From the carcinogenic point of view, besides benzo [a] pyrene (BaP), dibenz [a,h] anthracene (DbA) contributed most to the overall toxicity of PAHs, followed by BaA and BbF. BaPeq concentration from coal charging was 5.21-fold higher than that from coke pushing, indicating that different reuse ways should be considered based on their specific toxicity profiles of PAHs.

Evaluation of the new classification and surgical strategy for myasthenia gravis.

The aim of this study was to discuss the new methods of clinical classification and staging of patients with myasthenia gravis (MG) proposed by our group and to summarize the experiences of surgical treatment of MG with a novel incision by cutting the sternum cross-sectionally at the second intercostal level. A retrospective analysis was made for the clinical data from the patients with MG who underwent thymectomy from July 1988 to May 2009. The surgical procedures were designed into three groups, a group with Osserman classification and median incision of the sternum (Group 1), a group with MGFA typing (Myasthenia Gravis Foundation of America) and a small transverse sternal incision at the second intercostal level (Group 2), and a group with new typing and a smaller transverse sternal incision at the second intercostal level (Group 3). Observation of the clinical typing and staging was made in the patients with myasthenia crisis. The parameters such as procedure duration in Group 2 and 3 was significantly lower than those in Group 1 (P < 0.05). The incidence of myasthenia crisis in Group 3 was significantly lower than that in Groups 2 and 3 (P < 0.05). The procedure with a smaller transverse sternal incision at the second intercostal level (Group 3) is a safer method for patients with MG. The combination of this procedure with the new typing and staging methods proposed by our group could facilitate the selection of operation indications and opportunity, resulting in the lower incidence of myasthenia crisis and mortality. Our new procedure is well deserved to be a preferential selection by other hospitals.

The genetic profiling of preferentially expressed genes in murine splenic CD8α+ dendritic cells.

In the murine splenocytes, CD8α+ dendritic cells (abbreviated as 8+DC) and CD8α- dendritic cells (abbreviated as 8-DC) are identified with some vague features for each of them. 8+DCs but not 8-DCs cross-prime cytotoxic T cells in vivo. We aim to distinguish the two subtypes of DC based on gene expression profiling. Suppressive subtractive hybridization was undertaken to get differentially expressed genes from such subtracted cDNA library specific to 8+DC. A total of 114 sequences from the subtracted cDNA library specific to 8+DC library were analyzed. Most of them are known proteins, but some of them were novel, either totally novel genes or homologs to known genes, but with novel exon. About 55 probably novel exons were discovered, and 11 exons had longer length than those in gene bank. The clones 12, 44, 79, and 110 have no match with known sequences in gene bank. Then, semi-quantitative PCR was done to compare the expression of the enriched sequences between 8+DC and 8-DC. About 14 genes are differentially expressed in 8+DC. Therefore, SSH is an effective method to clone differentially expressed genes for 8+DC compared to 8-DC.

A novel agonistic anti-human death receptor 5 monoclonal antibody with tumoricidal activity induces caspase- and mitochondrial-dependent apoptosis in human leukemia Jurkat cells.

An agonistic antibody against TNF-related apoptosis-inducing ligand death receptor 5 (DR5) is a practicable candidate drug for antitumor therapy. In this study, a novel murine anti-human DR5 monoclonal antibody, mDRA-6(IgG1-κ), has been generated. This study aimed to explore the caspase-dependent and mitochondrial mechanisms of mDRA-6 in inducing apoptosis in human leukemia Jurkat cells. The apoptotic effects of mDRA-6 on Jurkat cells, which express DR5 on the cell surface, were detected by flow cytometry and western blot after exposure to different doses of mDRA-6 and at fixed doses of mDRA-6 at different times. It was demonstrated that mDRA-6 can induce Jurkat cell apoptosis via caspase- and mitochondrial-dependent pathways. These results indicate that the novel antibody mDRA-6 against DR5 has an antitumor function and may provide a new reagent for tumor therapy.

catena-Poly[[[diaqua-terbium(III)]-µ-6-carboxy-nicotinato-µ-pyridine-2,5-di-carboxyl-ato] dihydrate].

The title compound, {[Tb(C(7)H(3)NO(4))(C(7)H(4)NO(4))(H(2)O)(2)]·2H(2)O}(n), is isotypic with the analogous Tm(III) compound [Li, Zhang, Wang & Bai (2009). Acta Cryst. E65, m411]. The Tb(III) atom is octa-coordinated by two water mol-ecules and by four carboxyl-ate O atoms and two pyridyl N atoms from two pyridine-2,5-dicarboxyl-ate (2,5-pydc) and two 6-carboxy-nicotinate (2,5-Hpydc) ligands. The 2,5-pydc and 2,5-Hpydc ligands bridge Tb(III) atoms, generating helical coordination polymers along [001]. An extensive network of O-H⋯O hydrogen bonds is formed between the coordination polymers and the uncoordinated water mol-ecules. The refined Flack parameter of 0.54 (2) suggests inversion twinning.

[Synergistic lethal effect of mDRA-6 and nimesulide on human hepatocellular cancer cell line SMMC-7721].

BACKGROUND & OBJECTIVE: Both mDRA-6, a monoclonal antibody of death receptor 5 (DR5) in human cells prepared by our key laboratory, and nimesulide, a specific cyclooxygenase-2 (COX-2) inhibitor, can induce apoptosis of some malignant tumor cells. This study was to investigate the lethal effects of mDRA-6 and nimesulide on human hepatocellular cancer cell line SMMC-7721, and explore the possible mechanism. METHODS: The expression of DR5 on SMMC-7721 cells was detected by flow cytometry (FCM). SMMC-7721 cells were treated with mDRA-6 and nimesulide alone or in combination. Cell morphology was observed under microscope with Hoechst33258 staining. Cytotoxicity was examined by MTT assay. Cell apoptosis was detected by FCM. RESULTS: The positive rate of DR5 on SMMC-7721 cells was 95.0%. The apoptosis of SMMC-7721 cells could be induced by both mDRA-6 and nimesulide: the apoptosis rates were 10.5% when treated with 25 ng/mL mDRA-6 for 12 h, 35.0% when treated with 1 600 ng/mL mDRA-6, 5.0% when treated with 200 micromol/L nimesulide, and 34.0% when treated with 800 micromol/L nimesulide. The combination of mDRA-6 and nimesulide exhibited synergistic effect on the apoptosis of SMMC-7721 cells (q=1.23): the apoptosis rates were 31.2% when treated with 200 micromol/L nimesulide and 25 ng/mL mDRA-6 for 12 h, and 91.1% when treated with 200 micromol/L nimesulide and 1 600 ng/mL mDRA-6 for 12 h. CONCLUSIONS: Both mDRA-6 and nimesulide can induce the apoptosis of SMMC-7721 cells. The combination of mDRA-6 and nimesulide exhibits synergistic lethal effect on SMMC-7721 cells.

[Leukemic cell apoptosis induced by anti-human DR5 monoclonal antibody mDRA-6].

AIM: To investigate the apoptotic effect of anti-human DR5 (death receptor 5 of TRAIL) monoclonal antibody mDRA-6 on leukemic cells. METHODS: The morphological changes of leukemic cells were observed by fluorescence microscope. The cytotoxic and apoptotic effects of mDRA-6 on Jurkat, HL-60 and K562 cells were detected by MTT analysis and flow cytometry with Annexin V-FITC/PI staining. RESULTS: Chromatin condensation, budding and apoptotic bodies were observed in Jurkat and HL-60 cells treated by mDRA-6. Death and apoptosis of leukemic cells treated by mDRA-6 were increased, but the effect of mDRA-6 on K562 cells was not obvious. CONCLUSION: Apoptosis of leukemic cells can be induced by anti-human DR5 monoclonal antibody mDRA-6. Different leukemic cell lines are of different sensitivity to mDRA-6.

[Adriamycin enhances anti-human DR5 monoclonal antibody (mDRA-6) induced HL-60 cells apoptosis].

OBJECTIVE: To investigate synergistic killing effect of anti-human DR5 (death receptor 5 of TRAIL) monoclonal antibody (mDRA-6) and adriamycin(Adr) on HL-60 cells. METHODS: mDRA-6 was prepared by immunizing BALB/c mice with DR5 protein. DR5 expression on Adr-treated HL-60 cells was detected by flow cytometry. Morphologic changes of HL-60 cells were observed under fluorescence microscope. Cytotoxic and apoptotic effects of mDRA-6 and Adr on HL-60 cells were measured by MTT analysis. DNA fragmentation was detected by agarose gel electrophoresis. RESULTS: Adr induce DR5 expression on HL-60 cells. Cell budding, chromatin condensation and apoptotic body formation were observed in HL-60 cells treated by mDRA-6 and Adr. Death and apoptosis of these cells and DNA ladder were exhibited on agarose gel electrophoresis. CONCLUSION: mDRA-6 and Adr have synergistic killing effect on HL-60 cells.

[Cytotoxic mechanism of anti-human death receptor 5 monoclonal antibody mDRA-6].

AIM: To investigate the cytotoxic action and its mechanism of a novel anti-human DR5 monoclonal antibody (mAb mDRA-6). METHODS: The cytotoxic action of mAb mDRA-6 on Jurkat cells and the effects of inhibitors of caspase 8 and caspase 9 on apoptosis of Jurkat cells induced with mAb mDRA-6 were detected by flow cytometry. The effects of mAb mDRA-6 on the morpha of Jurkat cells was observed by fluorescence microscope. The apoptosis of Jurkat cells was detected by flow cytometry with Annexin V-FITC/PI staining. The DNA fragmentation in Jurkat cells was analysed by agrose gel electrophoresis. RESULTS: mAb mDRA-6 exerted cytotoxicity on Jurkat cells in dose-dependent and time-dependent manner. Jurkat cells treated with mDRA-6 exhibited typical apoptostic features in morphology, namely, membrane crenation, bubbling, chromatin condensation, and formation of apoptotic bodies. The flow cytometry analysis showed that phosphatidylserine (PS) was highly expressed in Jurkat cells treated with mDRA-6. Agrose gel electrophoresis indicated that DNA fragmentation occurred in Jurkat cells. Inhibitor of caspase 8 inhibited the apoptosis of Jurkat cells induced with mDRA-6 while Inhibitor of caspase 9 showed less effect. CONCLUSION: mDRA-6 may exert cytotoxicity by inducing Jurkat cell apoptosis through signal transduction pathway of death receptors, which may be a useful tool in treating tumors with DR5 as target molecule and exploring the functional domain of DR5.