To observe the protective effects of puerarin on radiation injury of experimental rats and to discuss the possible mechanism of its radiation protection.

The biological activity of ADCC by anti-CD20 monoclonal antibody was determined by BioGlo™ Luciferase Assay System using Jurkat/NFAT-luc+FcγRIIIa cell line as effector cell and WIL2-S cell line as target cell. The developed method was verified for specificity, precision and accuracy. Anti-CD20 monoclonal antibody showed a dose-response mode by the developed method, and the determination result complied with the following four-parameter equation: y = (A-D)/[1 + (X/C)(B)] + D. The optimized parameters of the method were determined including the antibodies diluted concentration (18,000 ng·mL(-1)), dilution rate (1:5), the ratio of effector cell and target cell (6:1), and induction time (6 h). The values of eight independent tests have passed a statistical test for curve regression analysis, linear or parallelism, which showed the method possessed good specificity. Four different dilute groups of recovery rates sample were determined for 3 times, and the result showed mean relative potencies of (44.39±3.93)%, (72.74±2.78)%, (128.28±7.01)% and (168.19±2.70)% respectively, with a variation coefficient of less than 10%, and the recoveries of (88.78±7.85)%, (96.99±3.70)%, (102.63±5.61)% and (112.12±1.80)% respectively. A novel reporter gene method for determination of biological activity of ADCC by anti-CD20 monoclonal antibody was successfully developed, which showed strong specificity, good reproducibility and high accuracy, and might be used routinely.

Here we discuss whether N terminal sequencing is appropriate as one of the conventional control methods for monoclonal antibody products. We determined the N terminal sequences of two monoclonal antibody products targeting two antigens separately with both Edman degradation and mass peptide spectrometry. We also identified the characteristic peptide fragments with mass spectrometry. Furthermore, we analyzed their heterogeneity with ion exchange chromatography, capillary zone electrophoresis and Imaged Capillary Isoelectric Focusing. Edman degradation method showed that the N terminal 15 amino acids of heavy and light chains of the two monoclonal antibodies were identical. Peptide mass spectrometry demonstrated that T1 peptide fragments of heavy and light chains of the two antibodies were also the same. But in contrast, peptide mapping and the three analytical methods for heterogeneity analysis could effectively identify and differentiate the two antibodies. The N terminal sequences of two monoclonal antibodies are identical because the number of framework sequences of humanized or human monoclonal antibodies is relatively limited, so whether N terminal sequencing analysis could be regulated as one of the practical control methods should be carefully discussed. Our work also proves that the above analytical methods could combinatorially applied to the identification of monoclonal antibody products, and are more objective compared to N terminal sequencing.
Amino Acid Sequence ; Antibodies, Monoclonal ; isolation & purification ; Chromatography, Ion Exchange ; Humans ; Isoelectric Focusing ; Mass Spectrometry ; Peptide Mapping ; Peptides ; Sequence Analysis, Protein ; methods

Objective To analyze the differences of size and charge heterogeneities between origi-nal humanized anti-TNF-αantibody and four similar biotherapeutic products ( SBP ) .Methods The size exclusion chromatography ( SEC-HPLC ) and weak cation exchange chromatography ( WCX-HPLC ) were used to analyze the size and charge heterogeneities , respectively.Carboxypeptidase B (CpB) treatment was employed to analyze the source of charge heterogeneity of the antibody products .Results Four SBPs showed the same pattern with the originator in SEC-HPLC, and no significant difference with the percentage of mono-mer was observed .The percentages of the aggregates of SBP-3 and SBP-4 were a little higher than those of the originator .The charge distribution of SBPs was significantly different from the originator ′s, especially in the basic region .The results from the samples treated with CpB indicated that the difference of charge distri -bution in the basic region might be caused by the C-terminal lysine variants .Conclusion Four SBPs showed similar size heterogeneity with the originator , but significant differences with charge heterogeneity were observed among them .The study suggested that more attention should be paid to the charge heterogene -ity analysis of the biosimilar products .

Objective To compare the capability of capillary electrophoresis-sodium dodecyl sul-fate ( CE-SDS) and size exclusion-high performance liquid chromatography ( SE-HPLC) for analysis of size heterogeneity of monoclonal antibody products .Methods The size heterogeneity of one humanized anti-VEGF monoclonal antibody was analyzed by using non-reduced and reduced CE-SDS, and conventional , de-natured and denatured reduced SE-HPLC.Results The percentage of aggregates detected by non-reduced CE-SDS (0.82%±0.01%) was equal to that by using denatured SE-HPLC (1.05%±0.02%), but it was significantly lower than that by using conventional SE-HPLC analysis (5.08%±0.10%).With regard to fragments analyzed with non-reduced antibodies, its percentage was (7.12±0.04)% measured by non-re-duced CE-SDS analysis that was significantly higher than that by conventional SE -HPLC analysis (0.02%± 0.01%) and denatured SE-HPLC analysis (0.62%±0.01%).Using reduced antibodies , the percentage of fragments was (3.19±0.50)%tested by reduced CE-SDS analysis that was significantly higher than that by using denatured reduced SE-HPLC analysis (0.07%±0.01%).Conclusion Conventional SE-HPLC was more objective than CE-SDS for content analysis of aggregates , as both the covalent and non-covalent forms of aggregates could be detected .Non-reduced CE-SDS could demonstrate the content of clips , while reduced CE-SDS showed the degraded fragments .Therefore, CE-SDS had an advantage over conventional SE-HPLC for content analysis of fragments .The use of the two analytical methods in combination provided solid techni-cal supports for the quality control of size heterogeneity of monoclonal antibodies .

Aim To observe the effects of promethazine on the analgesia,hypnosis,amnesia and therapeutic index of isoflurane.Methods The experiments were designed to study promethazine on the analgesic effect of isoflurane by hot-plate test and writhing test,and to study the effect of promethazine on the sleeping time of isoflurane by the method of righting reflex,and the amnesia of isoflurane by Morris water maze,and the ED_(50),LD_(50) by sequential method in mice.Results The result of hot-plate test and writhing test indicated that promethazine could enhance the analgesic effect of isoflurane(P＜0.05 or P＜0.01);through the experiment of righting reflex, sleeping time of isoflurane in mice was extended by promethazine(P＜0.01);in Morris water maze experiment, the average latency in the combination of promethazine and isoflurane was longer than that of the promethazine group or isoflurane group(P＜0.05 or P＜0.01), while aiming to the residence time, the combination of the two was shorter than that in the third quadrant(P＜0.01 or P＜0.05),the TCPP of the group of isoflurance was more than that of the combination group;promethazine could decrease the ED_(50) of isoflurance(P＜0.01),but it did not obviously affect its LD_(50)(P＞0.05).Conclusion Promethazine can not only reinforce the effect of isoflurance on analgesia,hypnosis and amnesia, but also boost the therapeutic index of isoflurance.

This paper reports the determination of the drug antibody ratio in an antibody-drug conjugate with two methods, i.e. LC-MS and UV/VIS, and to provide a reliable method to scientifically evaluate and effectively control the drug antibody ratio. Deglycosylated sample was analyzed with C4 column followed by MS, and the number of conjugated drugs in the antibody was determined by the molecular weight increase due to the addition of different number of drugs to the antibody, and then drug antibody ratio was calculated by weighted average of different number of drugs conjugated to the antibody. Optical density at 252 and 280 nm was measured with UV/VIS, and due to the difference of extinction coefficients between the antibody and the drug, the drug antibody ratio was calculated from linear equation with two unknowns. The drug antibody ratio was 3.21 and 3.25 respectively measured by the two methods, and the results were similar with the two methods. Our study indicated that both methods, LC-MS and UV/VIS, could be applied to the analysis of drug antibody ratio of the antibody drug conjugate.

OBJECTIVETo investigate the impact of aquaporin 9 (AQP9) on the proliferation,apoptosis,invasiveness and migration of hepatocellular carcinoma cells using the HepG2 cell line.

METHODSA lentiviral vector targeting the coding region of human AQP9 was constructed. The recombinant lentiviral vector was harvested from the 293T cell line and transfected into the HepG2 cell line; resistant cell clones were selected with puromycin. Three groups of cells were established, including the CC group (control without lentiviral vector), the PWPI group (control with empty carrier virus), and the AQP9 overexpression group (experimental with the AQP9 recombinant virus). Transfection efficiency was validated by laser confocal microscopy.Expression of AQP9 was detected in the transfected HepG2 cells by westem blotting (protein) and real-time qPCR (mRNA). AQP9 effects on proliferation, migration, invasion and apoptosis of the HepG2 cell line were assessed by plate colony formation assay, woumd healing assay, transwell assay and flow cytometry.

RESULTSThe green fluorescent protein of the recombinant lentiviral vector was appropriately distributed in the cell membrane. The AQP9 overexpression group showed significantly higher AQP9 mRNA and protein levels than the PWPI group and the CC group (both P < 0.01). Cells with AQP9 overexpression showed a lower colony formation rate (16.93±3.19% vs. CC group: 23.53±2.10% and PWPI group: 23.00±2.02%; F=6.46, P=0.032) and a lower overall apoptosis rate (44.96±3.53% vs. CC group:19.7±2.49% and PWPI group: 24.37±2.38%; F=66.88, P < 0.01). The AQP9 overexpression group also showed significantly higher number of cells in the G1 stage and significantly lower number of cells in the S stage (G1: 66.58±0.99% and S:15.25±1.81%), significantly smaller cell migration distance (P=0.01 < 0.05), and significantly suppressed invasiveness (17±8 vs. CC group:109+/-9 and PWPI group: 95±11; P=0.01 < 0.05).

CONCLUSIONIn HepG2 cells, AQP9 significantly reduces the migrative and invasive capabilities, induces cell apoptosis, and inhibits cell proliferation via cell cycle arrest at the G1/S phases.

Apoptosis ; Aquaporins ; Cell Movement ; Cell Proliferation ; Genetic Vectors ; Hep G2 Cells ; Humans ; Lentivirus ; Neoplasm Invasiveness ; RNA, Messenger ; Transfection

Objective To investigate the effect of combining electroacupuncture with nerve mobilization to improve lower extremity motor function after sciatic nerve injury. And to document any changes in mRNA and protein expression of Ras-related C3 botoxin substrate 1. Methods 180 New Zealand rabbits were randomly divided into a normal control group, a model control group, an electroacupuncture group, a nerve mobilization group, and an elec-troacupuncture combined with nerve mobilization group, each of 36. Sciatic nerve injury was modelled using the clam-ping method in all except the normal control group. The control group had no intervention, while the nerve mobiliza-tion group, the electroacupuncture group and the combined group were treated with nerve mobilization, and/or elec-troacupuncture applied to the rabbit analogue of the jiaji acupoint. After 1, 2, and 4 weeks of treatment, toe reflex scores and modified Tarlov scores were used to assess any functional recovery. After 1, 2, and 4 weeks of treatment, 12 of the rabbits in each group were sacrificed and the sciatic nerve and the L4-L6 segments of the spinal cord were re-sected. The expression of Ras-related C3 botoxin substrate 1 mRNA and protein was detected using the polymerase chain reaction and western blotting. Results Sciatic nerve function and the expression of Ras-related C3 botoxin sub-strate 1 mRNA in the spinal cords and sciatic nerves of the three treatment groups were significantly higher than in the model control group at all three time points, but significantly lower than in the normal control group. The combined group′s results were significantly better than with electroacupuncture or nerve mobilization alone. After 1, 2, and 4 weeks of treatment, the average expression of Ras-related C3 botoxin substrate 1 protein in the spinal cords of the three treatment groups was significantly higher than the model control group′s average, but significantly lower than that of the normal control group at the same time point. After 1 week of treatment the average expression of Ras-related C3 botoxin substrate 1 protein in the spinal cords of the combined group was significantly higher than that in the group receiving electroacupuncture alone. After 2 and 4 weeks it was also significantly higher than the nerve mobilization group′s aver-age. After 1 week of treatment, the average expression of Ras-related C3 botoxin substrate 1 protein in the sciatic nerves of all three treatment groups was significantly lower than that of the control group. However, 1 and 3 weeks later the av-erage protein expression in the sciatic nerves was significantly higher than in the model control group, but significantly lower than in the normal control group at the same time points. The combined group′s average was then significantly higher than those of the groups receiving electroacupuncture or nerve mobilization alone at the same time point. Conclusion Nerve stimulation combined with electroacupuncture applied to the jiaji acupoint can promote the regener-ation of axons after sciatic nerve injury. The mechanism may be related to up-regulation of the Ras-related C3 botoxin substrate 1 gene and protein expression in the injured sciatic nerve and corresponding spinal cord segments.

T cell immunoglobulin and ITIM domain (TIGIT) is a novel immune checkpoint that has been considered as a target in cancer immunotherapy. Current available bioassays for measuring the biological activity of therapeutic antibodies targeting TIGIT are restricted to mechanistic investigations because donor primary T cells are highly variable. Here, we designed a reporter gene assay comprising two cell lines, namely, CHO-CD112-CD3 scFv, which stably expresses CD112 (PVRL2, nectin-2) and a membrane-bound anti-CD3 single-chain fragment variable (scFv) as the target cell, and Jurkat-NFAT-TIGIT, which stably expresses TIGIT as well as the nuclear factor of activated T-cells (NFAT) response element-controlled luciferase gene, as the effector cell. The anti-CD3 scFv situated on the target cells activates Jurkat-NFAT-TIGIT cells through binding and crosslinking CD3 molecules of the effector cell, whereas interactions between CD112 and TIGIT prevent activation. The presence of anti-TIGIT mAbs disrupts their interaction, which in turn reverses the inactivation and luciferase expression. Optimization and validation studies have demonstrated that this assay is superior in terms of specificity, accuracy, linearity, and precision. In summary, this reliable and effective reporter gene assay may potentially be utilized in lot release control, stability assays, screening, and development of novel TIGIT-targeted therapeutic antibodies.