1.Effect of cell culture conditions on antibody heterogeneity.
Xujie DUAN ; Rui LIU ; Weitao XU ; Tong REN ; Houyong LUO
Chinese Journal of Biotechnology 2013;29(12):1880-1886
With the advantage of clear target and little side effect, antibody drug has attracted widely attention of worldwide pharmaceutical companies. However, large scale mammalian cell culture and antibody quality analysis are the bottlenecks of antibody drug industrialization in China. Especially due to the significant effect of cell culture conditions on antibody heterogeneity. Therefore, it is extremely urgent to optimize cell culture conditions to favor the demands of antibody drug development. This review summarized the most recent advances in the effect of cell culture conditions on antibody quality, followed by addressing the key issues that might be strategically important for domestic antibody drug development.
Animals
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Antibodies, Monoclonal
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biosynthesis
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isolation & purification
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Antibody Formation
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Cell Culture Techniques
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methods
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trends
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Genetic Heterogeneity
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Protein Stability
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Quality Control
2.Distinctive Feature of Application of Radiofrequency Current Ablation to Aged Patients with Tachycardia
Xujie FU ; Riying DU ; Xinguo YANG ; Yusheng XUE ; Yinglong HOU ; Jinglan LUO ; Yi WANG ;
Journal of Interventional Radiology 1994;0(03):-
14 aged patients received radiofrequency current ablation(RFCA)to treat drug-refractory tachycardia. The success rate was 97%(13/14).In conjunction with the charcteristicaof aged patients often with long clinical history and apt to be complicated,the paper especially discussed the distinctive feature of application of RFCA to aged patients.
3.Impact of remote postconditioning on rabbit hearts with acute myocardial ischemia-reperfusion injury
Chunmei LI ; Xinghua ZHANG ; Xiaojing MA ; Man LUO ; Xujie LIU ; Guodong WANG
Chinese Journal of Pathophysiology 2000;0(12):-
AIM: In this study,we tested the hypothesis that remote postconditioning induced by a single 5-min episode of femoral artery occlusion and reperfusion applied immediately before the onset of coronary artery reperfusion protects the myocardium from reperfusion injury.METHODS: Thirty healthy New Zealand white rabbits were randomly divided into three groups(n=10 in each group): control,myocardial ischemic postconditioning(MIP) and Limb ischemic postconditioning(LIP).Myocardial infarct size and tissue myeloperoxidase(MPO) activity were determined at the end of the experiment.Plasma creatine kinase(CK) activity and malondialdehyde(MDA) levels were measured at baseline,the end of ischemia,and after 180 min of reperfusion,respectively.RESULTS: Myocardial infarct size was significantly reduced in MIP and LIP as compared to control(P
4.Bladder installation of alkaline lidocaine for the treatment of ketamine-associated cystitis
Hui WEI ; Ying HUANG ; Xiaozhong ZHANG ; Zhigang CHEN ; Guo LI ; Xujie LUO ; Shaohong FANG ; Shaowen WU ; Hua MEI
Chinese Journal of Urology 2010;31(9):621-623
Objective To evaluate the efficacy and safety of intravesical alkalised lidocaine therapy for the treatment of ketamine-associated cystitis. Methods From 2008 to 2009,7 cases of patients (6 males and 1 female; mean age 26 years) were admitted with severe lower urinary tract symptoms (LUTS). Three cases had painful hematuria. All cases had history of abuse ketamine. B ultrasound examination revealed marked thickness of the bladder wall and small bladder capacity. Urodynamic study were performed showing the functional bladder capacities between 20 to 100 ml(average 50 ml),Qmax between 3.7 to 10.8 ml/s, RUV between 0 to 24 ml. Urodynamic analyses showed hypersensitive bladder and decreased bladder compliance. Cystoscopy showed diffuse reddish swelling of the bladder mucosa and hemorrhagic cystitis. All patients were required to withdraw the ketamine and treated with bladder hydrodistention therapy (intravesical alkalised lidocaine with heparin). Results The biopsies of 2 patients showed bladder wall inflammation and fibrosis. LUTS was significantly relieved after bladder installation within 7 days. The functional bladder capacities increased between 150±30 ml,Qmax 11.5±3.8 ml/s. Four cases became asymptomatic. Three recurrent cases after reabused ketamin for 1 to 3 months received same intraversical treatment. All cases were followed up for 2 to 17 months. Conclusion Intravesical hydrodistention therapy with alkalised lidocaine and heparin could be the safe and effective therapy in the treatment of katamine-associated cystitis.
5.Effects and mechanism of pyrroloquinoline quinine on mitochondrial function and cell survival of rat bone marrow mesenchymal stem cells under oxidative stress
Xujie WANG ; Yunshu YANG ; Kuo SHEN ; Jing WANG ; Fu HAN ; Gaofeng WU ; Yan LI ; Xiaozhi BAI ; Liang LUO ; Dahai HU
Chinese Journal of Burns 2020;36(5):378-387
Objective:To observe the effects of pyrroloquinoline quinine (PQQ) on the mitochondrial function and cell survival of rat bone marrow mesenchymal stem cells (BMSCs) under oxidative stress, and to explore its mechanism.Methods:BMSCs of rats were cultured in vitro with Dulbecco′s minimum essential medium/F12 medium containing fetal bovine serum in the volume fraction of 10% (hereinafter referred to as normal medium). The rat BMSCs of third to fifth passages in logarithmic growth phase were selected for the following experiments. (1) The cells were divided into normal control group, normal control+ PQQ group, hydrogen peroxide (H 2O 2) alone group, and H 2O 2+ PQQ group. The cells in normal control group were cultured in normal medium for 24 hours; the cells in normal control+ PQQ group were cultured in normal medium containing 100 μmol/L PQQ for 24 hours; the cells in H 2O 2 alone group were cultured in normal medium containing 200 μmol/L H 2O 2 for 24 hours; the cells in H 2O 2+ PQQ group were pre-incubated with normal medium containing 100 μmol/L PQQ for 2 hours, and then with H 2O 2 added to the concentration of 200 μmol/L and cultured for 24 hours. The cell morphology of each group was observed under the inverted phase contrast microscope, and the cell survival rate was detected by cell count kit 8 method. (2) Five batches of cells were collected, and the cells of each batch were divided into normal control group, H 2O 2 alone group, and H 2O 2+ PQQ group. The cells in each group received the same treatment as that in the corresponding group of experiment (1). After 24 hours of culture, one batch of cells was collected for apoptosis detection by flow cytometry, and the apoptosis rate was calculated. One batch of cells was subjected to mitochondrial membrane potential assay and JC-1 fluorescent staining observation using the JC-1 mitochondrial membrane potential detection kit and the inverted phase contrast fluorescence microscope, respectively. One batch of cells was collected for mitochondrial morphology observation under the transmission electron microscope. One batch of cells was subjected to catalase (CAT) and superoxide dismutase (SOD) activity assay by CAT activity assay kit and SOD activity assay kit, respectively. One batch of cells was subjected to Western blotting for determination of protein level of Epac1, adenine monophosphate activated protein kinase (AMPK), phosphorylated AMPK, cysteinyl aspartate-specific proteinase 3 (caspase-3), and cleaved caspase-3, and the phosphorylation level of AMPK and cleaved caspase-3/caspase-3 ratio were calculated. Six replicates were measured in each group for each index except for morphological observation. Data were statistically analyzed with one-way analysis of variance and independent sample equal variance t test. Results:(1) After 24 hours of culture, compared with those in normal control group (the cell survival rate was set to 100.0%), there was an increase in cell vacuole and a decrease in cell number in H 2O 2 alone group, and the cell survival rate was significantly reduced to (74.3±2.9)% ( t=6.39, P<0.01). Compared with those in H 2O 2 alone group, the cell morphology of H 2O 2+ PQQ group was significantly improved, and the cell survival rate was significantly increased to (116.9±4.2)% ( t=6.92, P<0.01); the cell survival rate in normal control+ PQQ group was (101.2±1.1)%, close to that of control group ( t=1.06, P>0.05). (2) After 24 hours of culture, compared with (13.6±1.0)% in normal control group, the apoptosis rate of cells in H 2O 2 alone group was significantly increased to (37.1±2.0)% ( t=10.57, P<0.01). Compared with that in H 2O 2 alone group, the apoptosis rate of cells in H 2O 2+ PQQ group was significantly declined to (17.0±0.7)% ( t=9.49, P<0.01). (3) After 24 hours of culture, compared with those in normal control group, the mitochondrial membrane potential of cells in H 2O 2 alone group was depolarized, the JC-1 fluorescent dye mainly existed in the cytoplasm in the form of monomer, which emitted green fluorescence, and a significant decrease in mitochondrial membrane potential was shown ( t=4.18, P<0.01). Compared with those in H 2O 2 alone group, the mitochondrial membrane potential of cells in H 2O 2+ PQQ group was increased to normal level ( t=4.43, P<0.01), and the JC-1 fluorescent dye accumulated in mitochondria following the polarized mitochondrial membrane potential and emitted red fluorescence. (4) After 24 hours of culture, compared with that in normal control group, the mitochondrial structure of cells in H 2O 2 alone group was disordered, with disappeared mitochondrial cristae and decreased mitochondrial matrix density. Compared with that in H 2O 2 alone group, the mitochondrial structure of cells in H 2O 2+ PQQ group was regular and intact, with clearly visible mitochondrial cristae and increased mitochondrial matrix density. (5) After 24 hours of culture, compared with those in normal control group, the CAT activity of cells in H 2O 2 alone group was significantly increased ( t=4.54, P<0.05), and the SOD activity was significantly decreased ( t=3.93, P<0.05). Compared with those in H 2O 2 alone group, the CAT activity of cells in H 2O 2+ PQQ group was obviously increased ( t=8.65, P<0.01), while there was no significant change in the SOD activity ( t=0.72, P>0.05). (6) After 24 hours of culture, compared with those in normal control group, the protein expression of Epac1 of cells in H 2O 2 alone group was significantly decreased ( t=4.67, P<0.01), while the AMPK phosphorylation level and the cleaved caspase-3/caspase-3 ratio were significantly increased ( t=7.88, 3.62, P<0.01). Compared with those in H 2O 2 alone group, the protein expression of Epac1 and the AMPK phosphorylation level of cells in H 2O 2+ PQQ group were both significantly increased ( t=4.34, 16.37, P<0.01), while the cleaved caspase-3/caspase-3 ratio was significantly declined ( t=3.17, P<0.05). Conclusions:Pretreatment with PQQ can improve the mitochondrial function, reduce cell apoptosis rate, and enhance cell survival rate of rat BMSCs under oxidative stress, which may be related to the up-regulation of Epac1 protein expression, activation of AMPK signaling pathway, and down-regulation of cleaved caspase-3 protein level.
6.Influence and its mechanism of allogeneic dermal papilla cells on the wound healing of full-thickness skin defects in mice
Yage SHANG ; Lixia ZHANG ; Chao HAN ; Mengyang LI ; Liang LUO ; Xujie WANG ; Dahai HU
Chinese Journal of Burns 2024;40(8):772-780
Objective:To explore the influence and its mechanism of allogeneic dermal papilla cells (DPCs) on the wound healing of full-thickness skin defects in mice.Methods:This study was an experimental study. DPCs were isolated from the whisker follicles of five 6-week-old male C57BL/6J mice by combining microdissection with collagenase digestion and were successfully identified. Eighteen 8-week-old male C57BL/6J mice were divided into phosphate buffer solution (PBS) group and DPC group according to the random number table, with 9 mice in each group, and the full-thickness skin defect wound model was created on the back of all mice. On day 2, 4, and 6 after injury, the mice in DPC group were administered 100 μL of cell suspension containing 1×10 6 DPCs of the 4 th passage by subcutaneous injection around the wound, and the mice in PBS group was administered an equal volume of PBS. On day 3, 7, 10, and 14 after injury, the wound healing and hair growth of mice in two groups were observed, and the residual wound area was measured, and the hair coverage area on the wound of mice in two groups was measured on day 14 after injury. On day 14 after injury, the wound tissue samples of mice in two groups were collected. Hematoxylin-eosin staining was performed to observe the condition of newborn hair follicles and the number was counted, Masson staining was performed to observe the collagen deposition in the dermis and the collagen deposition area was measured, the immunofluorescence method was used to detect the protein expressions of Wnt/β-catenin signaling pathway related molecules β-catenin and lymphoid enhancer binding factor 1 (Lef1), and Western blotting and real-time fluorescence quantitative reverse transcription polymerase chain reaction were used to detect the protein and mRNA expressions of β-catenin and Lef1, respectively. The number of samples in each experiment was 3. Results:Compared with those in PBS group, the mice in DPC group had accelerated wound re-epithelialization at each time point after injury, and more hair growth on day 10 and 14 after injury. On day 7, 10, and 14 after injury, the residual wound areas of mice in DPC group were (13.92±2.90), (3.69±1.78), and (1.09±0.14) mm 2, respectively, which were significantly smaller than (26.19±2.06), (10.84±3.59), and (6.75±2.11) mm 2 in PBS group, respectively (with t values of 5.85, 3.09, and 4.63, respectively, P values all <0.05). On day 14 after injury, the hair coverage area on the wound of mice in DPC group was (62±7) mm 2, which was significantly larger than (35±6) mm 2 in PBS group ( t=2.89, P<0.05). On day 14 after injury, compared with those in PBS group, the number of newborn hair follicles in the wound tissue of mice in DPC group was significantly increased ( t=5.43, P<0.05), and the dermal collagen deposition area was significantly reduced ( t=3.56, P<0.05). On day 14 after injury, both the immunofluorescence method and the Western blotting detection showed that the protein expressions of β-catenin (with t values of 5.49 and 4.25, respectively, P values all <0.05) and Lef1 (with t values of 7.50 and 11.54, respectively, P values all <0.05) in the wound tissue of mice in DPC group were significantly higher than those in PBS group; the mRNA expressions of β-catenin and Lef1 in the wound tissue of mice in DPC group were significantly higher than those in PBS group (with t values of 7.68 and 9.67, respectively, P<0.05). Conclusions:DPCs can accelerate the re-epithelialization of full-thickness skin defect wounds in mice by activating Wnt/β-catenin signaling pathway and promote hair follicle regeneration during the process of wound healing.