Correlation study on anti-Ro52 antibodies frequently co-occur with other myositis-specific and myositis-associated autoantibodies / 北京大学学报(医学版)

OBJECTIVE@#Anti-Ro52 antibodies are frequently co-occur with other myositis-specific and myositis-associated autoantibodies, we here to study this phenomenon in Chinese patients suspected with inflammatory myopathies.@*METHODS@#In the study, 1 509 patients clinically suspected with inflammatory myopathies were tested for 11 kinds of myositis-specific and myositis-associated autoantibodies (including: anti-Jo-1, PL-7, PL-12, EJ, OJ, Mi-2, SRP, Ku, PM-Scl 75, PM-Scl 100, and Ro52 antibo-dies) by line-blot immunoassay from 2010 to 2016 in Peking University First Hospital. This retrospective study was to analyze these results to reveal the characteristics of anti-Ro52 antibodies co-occuring with other myositis autoantibodies. The data were analyzed using SPSS 17.0 and Graph Pad PRISM for Chi-square test, independent t-test, Pearson's correlation analysis, and drawing statistical graphs. Significance level was set at P < 0.05.@*RESULTS@#The positive rate of anti-Ro52 antibodies was 18.3% (276/1 509 cases), which was the most frequently detected myositis antibodies in our center. 51.8% (143/276) of the patients with anti-Ro52 antibodies were combined with the other myositis antibodies, and the most common co-occurred antibodies were anti-SRP antibodies (18.8%, 52/276), and the second common co-occurred antibodies were anti-Jo-1 antibodies (13.0%, 36/276). Anti-Ro52 antibodies were the most common antibodies that co-occurred in other myositis antibodies positive patients except in anti-OJ antibodies positive group. The co-positive rate with anti-Ro52 antibodies was the lowest in anti-PM-Scl 75 positive group (30.4%, 31/102), and the highest in anti-EJ positive group (80.0%, 12/15). The positive rate of anti-Ro52 antibodies in anti-synthase antibodies (including anti-Jo-1, EJ, OJ, PL-7, and PL-12 antibodies) positive group was 57.3% (75/131), which was significantly higher than that in the other antibodies (including: anti-Mi-2, SRP, Ku, PM-Scl 75, and PM-Scl 100 antibodies) positive group with 35.2% (119/338) (χ2=18.916, P < 0.001). The intensity of anti-Jo-1, EJ, and SRP antibodies in the group of the patients that co-occurred with anti-Ro52 antibodies was significantly higher than that in the other group without anti-Ro52 antibodies respectively (P < 0.05). The intensity of anti-SRP antibodies was significantly correlated with that of anti-Ro52 antibodies (r=0.44, P=0.001).@*CONCLUSION@#Anti-Ro52 antibodies were commonly associated with other myositis-specific and myositis-associated autoantibodies, especially with anti-synthase antibodies, and the co-presence of anti-Ro52 antibodies may be correlated with the myositis antibody intensity.

Different Eukaryotic Initiation Factor 2Bε Mutations Lead to Various Degrees of Intolerance to the Stress of Endoplasmic Reticulum in Oligodendrocytes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Vanishing white matter disease (VWM), a human autosomal recessive inherited leukoencephalopathy, is due to mutations in eukaryotic initiation factor 2B (eIF2B). eIF2B is responsible for the initiation of protein synthesis by its guanine nucleotide exchange factor (GEF) activity. Mutations of eIF2B impair GEF activity at different degree. Previous studies implied improperly activated unfolded protein response (UPR) and endoplasmic reticulum stress (ERS) participated in the pathogenesis of VWM. Autophagy relieves endoplasmic reticulum load by eliminating the unfolded protein. It is still unknown the effects of genotypes on the pathogenesis. In this work, UPR and autophagy flux were analyzed with different mutational types.</p><p><b>METHODS</b>ERS tolerance, reflected by apoptosis and cell viability, was detected in human oligodendrocyte cell line transfected with the wild type, or different mutations of p. Arg113His, p. Arg269FNx01 or p. Ser610-Asp613del in eIF2Bε. A representative UPR-PERK component of activating transcription factor 4 (ATF4) was measured under the basal condition and ERS induction. Autophagy was analyzed the flux in the presence of lysosomal inhibitors.</p><p><b>RESULTS</b>The degree of ERS tolerance varied in different genotypes. The truncated or deletion mutant showed prominent apoptosis cell viability declination after ERS induction. The most seriously damaged GEF activity of p. Arg269FNx01 group underwent spontaneous apoptosis. The truncated or deletion mutant showed elevated ATF4 under basal as well as ERS condition. Decreased expression of LC3-I and LC3-II in the mutants reflected an impaired autophagy flux, which was more obvious in the truncated or deletion mutants after ERS induction.</p><p><b>CONCLUSIONS</b>GEF activities in different genotypes could influence the cell ERS tolerance as well as compensatory pathways of UPR and autophagy. Oligodendrocytes with truncated or deletion mutants showed less tolerable to ERS.</p>

Effects of quercetin on multidrug resistance and expression of related genes in human erythroleukemic K562/a cells / 中国实验血液学杂志

The study was aimed to investigate the effect of quercetin, flavonoid molecules on reversing leukemia multidrug resistance and its mechanism. K562/A cells were cultured in vitro with different concentrations of quercetin. Cell growth inhibition and adriamycin (ADR) sensitivity were detected by MTT method. Intracellular ADR concentration was determined by flow cytometry. Cell apoptosis was assayed by Annexin V/PI staining method. The expressions of drug transporter and apoptosis related genes were measured by real-time PCR array. The results indicated that quercetin inhibited the proliferation of K562 and K562/A in 5-160 µmol/L and with dose-dependent manner. Quercetin increased the sensitivity of K562/A cells to ADR in a low toxicity concentration. Flow cytometry showed that the quercetin increased the accumulation of ADR in K562/A cells when cells were co-cultured with 5 µmol/L ADR for 2 hours. Quercetin could induce the apoptosis of K562 and K562/A cells with dose dependent manner. Furthermore, some drug transport related genes such as ATP-binding cassette (ABC) and solute carrier (SLC) and some apoptosis-related genes such as BCL-2, tumor necrosis factor (TNF), tumor necrosis factor receptor (TNFR) families were down-regulated by quercetin. It is concluded that quercetin reverses MDR of leukemic cells by multiple mechanisms and the reversing effect is positively related to drug concentration.

Apoptosis-inducing effect of quercetin and kaempferol on human HL-60 cells and its mechanism / 中国实验血液学杂志

The purpose of this study was to explore the anti-leukemia effect of quercetin and kaempferol and its mechanism. The HL-60 cells were used as the leukemia models. The inhibitory effects of quercetin and kaempferol on growth of HL-60 cells was assessed by MTT assay. The effect of quercetin and kaempferol on cell cycle in HL-60 cells was detected by flow cytometry. The cytotoxic effect of these 2 drugs was analysed by single cell electrophoresis assay. Western blot analysis was used to study the apoptotic mechanism of HL-60 cells. The results showed that the quercetin and kaempferol had a significant anti-leukemia effect in vitro. The proliferation of HL-60 cells was significantly inhibited in dose-and time-dependent manners after treating with quercetin (r = 0.77) and kaempferol (r = 0.76) respectively, and the cytotoxicity of quercetin was superior to that of kaempferol. The quercetin and kaempferol induced G(2)/M arrest and apoptosis of HL-60 cells. The quercetin and kaempferol could down-regulate the survivin expression. It is concluded that the quercetin and kaempferol have significant anti-leukemia effect in vitro. Furthermore the apoptosis-inducing effect of quercetin is stronger than that of kaempferol, both of which induce apoptosis of HL-60 cells through depressing cell growth, arresting cell cycle and inhibiting expression of survivin.

Detection of multiple antibodies in myasthenia gravis and its clinical significance / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Antibodies against acetylcholine receptor, acetylcholinesterase, ryanodine receptor and titin have been found in patients with myasthenia gravis. However, the relations between these antibodies and character of myasthenia gravis are unknown. This study aimed to detect multiple antibodies in myasthenia gravis and to investigate its clinical significance.</p><p><b>METHODS</b>These antibodies were detected by enzyme-linked immunoabsorbent assay in 89 cases of myasthenia gravis, 66 cases of other neurological diseases and 66 healthy controls. The incidences of antibodies were compared using the chi-square test.</p><p><b>RESULTS</b>Acetylcholine receptor, acetylcholinesterase, titin and ryanodine receptor antibodies were detected in 53.9%, 20.2%, 64.0% and 55.0% of myasthenia gravis patients respectively, higher than in patients of other neurological diseases and controls groups. The combination of the four antibodies assays provided 94.4% sensitivity and 84.0% specificity for the diagnosis of myasthenia gravis. Acetylcholinesterase antibody occurred more frequently in acetylcholine receptor antibody negative patients with adverse reactions to neostigmine test. Titin antibody provided 82.1% sensitivity and 52.5% specificity for myasthenia gravis with thymoma. Incidences of titin and of ryanodine receptor antibody were higher in late onset myasthenia gravis than in early onset myasthenia gravis. The proportion of titin antibody positive patients increased with the severity of myasthenia gravis as graded by a modified Osserman scale.</p><p><b>CONCLUSIONS</b>Testing for acetylcholine receptor, acetylcholinesterase, titin and ryanodine receptor antibodies can offer a better diagnostic method for myasthenia gravis than each antibody test alone. Titin antibody combined with computed tomography was better for the diagnosis of thymoma. Titin antibody occurred most frequently in severe myasthenia gravis.</p>