BACKGROUND:The cryopreservation technology enables tissues/cells to be stored for a long time in a low-temperature environment while maintaining the integrity of their activity and function,which is of great significance for the construction of cell therapy,tissue engineering and biological sample banks.Cryoprotective agents often contain dimethyl sulfoxide and serum.To avoid the toxic side effects of dimethyl sulfoxide,the complexity of serum components and immune responses,although some finished cryoprotective agents have been marketed,they are faced with many difficulties such as high cost and limited application.Therefore,there is an urgent need to develop a cryoprotective agent with clear components and the ability to solve the above problems.OBJECTIVE:To evaluate the effects of a novel cryoprotectant on cryopreservation efficiency of different tissue and cell sources.METHODS:By applying the novel cryoprotectant as an experimental group with the commercially available and widely used cryoprotectant(control group)to umbilical cord Wharton's jelly tissue,umbilical cord mesenchymal stem cells,umbilical cord blood/peripheral blood mononuclear cells,NK and CIK cells,comparative analyses were conducted in terms of cell morphology,number,viability,surface markers,differentiation potential,and cell-killing toxicity assay before cryopreservation and after resuscitation thawing.We confirmed the cryopreservation effect of the new cryoprotectant and its potential application value.RESULTS AND CONCLUSION:(1)The novel cryoprotectant facilitated the normal growth of cryopreserved Wharton's jelly tissue upon recovery,exhibiting mesenchymal stem cell morphology.No significant differences were observed between the experimental and control groups in terms of cell recovery rate,surface markers,and differentiation potential.(2)There was no significant difference in the number and viability of cells between the experimental group and the control group after cryopreservation of cord blood/peripheral blood mononuclear cells,and the cryo-resuscitated cell numbers and viability of derived NK cells/CIK cells did not show significant difference between the experimental and control groups.(3)For NK cells derived and differentiated from cord blood/peripheral blood mononuclear cells,there was no significant difference in the proportion of CD56+CD16+cell subpopulations between the experimental group and the control group.For CIK cells derived and differentiated from cord blood/peripheral blood mononuclear cells,there was no significant difference in the proportions of CD3+CD8+and CD3+CD56+cell subpopulations between the experimental group and the control group.(4)In terms of cytotoxicity testing,when the effective-target ratio of immune cells and melanoma cell line Mel624 was 20:1,whether it was NK cells/CIK cells derived from cord blood or peripheral blood mononuclear cells,there was no significant difference in the tumoricidal activity of cells between the experimental group and the control group.These findings suggest that the novel cryoprotectant can replace existing commercially available and widely used cryoprotectants,and is applicable to Wharton's jelly tissue,umbilical cord mesenchymal stem cells,umbilical cord blood/peripheral blood mononuclear cells,as well as NK and CIK cells,providing a solid technical foundation for the scaling,standardization,and commercialization of universal cryoprotectants.

BACKGROUND:The cryopreservation technology enables tissues/cells to be stored for a long time in a low-temperature environment while maintaining the integrity of their activity and function,which is of great significance for the construction of cell therapy,tissue engineering and biological sample banks.Cryoprotective agents often contain dimethyl sulfoxide and serum.To avoid the toxic side effects of dimethyl sulfoxide,the complexity of serum components and immune responses,although some finished cryoprotective agents have been marketed,they are faced with many difficulties such as high cost and limited application.Therefore,there is an urgent need to develop a cryoprotective agent with clear components and the ability to solve the above problems.OBJECTIVE:To evaluate the effects of a novel cryoprotectant on cryopreservation efficiency of different tissue and cell sources.METHODS:By applying the novel cryoprotectant as an experimental group with the commercially available and widely used cryoprotectant(control group)to umbilical cord Wharton's jelly tissue,umbilical cord mesenchymal stem cells,umbilical cord blood/peripheral blood mononuclear cells,NK and CIK cells,comparative analyses were conducted in terms of cell morphology,number,viability,surface markers,differentiation potential,and cell-killing toxicity assay before cryopreservation and after resuscitation thawing.We confirmed the cryopreservation effect of the new cryoprotectant and its potential application value.RESULTS AND CONCLUSION:(1)The novel cryoprotectant facilitated the normal growth of cryopreserved Wharton's jelly tissue upon recovery,exhibiting mesenchymal stem cell morphology.No significant differences were observed between the experimental and control groups in terms of cell recovery rate,surface markers,and differentiation potential.(2)There was no significant difference in the number and viability of cells between the experimental group and the control group after cryopreservation of cord blood/peripheral blood mononuclear cells,and the cryo-resuscitated cell numbers and viability of derived NK cells/CIK cells did not show significant difference between the experimental and control groups.(3)For NK cells derived and differentiated from cord blood/peripheral blood mononuclear cells,there was no significant difference in the proportion of CD56+CD16+cell subpopulations between the experimental group and the control group.For CIK cells derived and differentiated from cord blood/peripheral blood mononuclear cells,there was no significant difference in the proportions of CD3+CD8+and CD3+CD56+cell subpopulations between the experimental group and the control group.(4)In terms of cytotoxicity testing,when the effective-target ratio of immune cells and melanoma cell line Mel624 was 20:1,whether it was NK cells/CIK cells derived from cord blood or peripheral blood mononuclear cells,there was no significant difference in the tumoricidal activity of cells between the experimental group and the control group.These findings suggest that the novel cryoprotectant can replace existing commercially available and widely used cryoprotectants,and is applicable to Wharton's jelly tissue,umbilical cord mesenchymal stem cells,umbilical cord blood/peripheral blood mononuclear cells,as well as NK and CIK cells,providing a solid technical foundation for the scaling,standardization,and commercialization of universal cryoprotectants.

OBJECTIVE: To investigate the persistent damage of learning and memory ability after the cessation of sub-chronic manganese(Mn)-exposure in rats. METHODS: Specific pathogen free weaning male SD rats were randomly divided into control group and low-, medium-and high-dose groups based on body weight, with 6 rats in each group. Rats were intraperitoneally injected with Mn chloride(MnCl_2·4 H_2O) at the concentrations of 0, 5, 10, or 20 mg/kg body weight, 5 days per week for 6 weeks and continued to be observed for 12 weeks after the cessation of Mn-exposure. During the experiment, the body mass of the rats was weighed. Learning and memory ability was evaluated by a Morris water-maze task at the 6 th weeks of Mn-exposure(cessation of Mn-exposure of week 0), the 6 th and 12 th week of the cessation of Mn-exposure. The organ coefficients of heart, liver, spleen, kidney and testicles were evaluated after the cessation of Mn-exposure on week 12. RESULTS: The body mass of the high-dose group was lower than that of the other 3 groups(P<0.05) at the 4 th and 6 th week of Mn-exposure and the 2 nd week of the cessation of Mn-exposure. There was no significant difference in body mass between the groups(P>0.05) on the 12 th week of the cessation of Mn-exposure. The escape latency of high-dose group was higher than that of the control group(P<0.05), and the number of platform crossings in the low-, medium-and high-dose groups were fewer than that in the control group(P<0.05) after the cessation of Mn-exposure. The escape latency was shorter and the numbers of platform crossings were higher on the 6 th and 12 th week of the cessation of Mn-exposure(P<0.05) when compared with that of the 6 th week of Mn-exposure rats. There was no statistical significance in the organ coefficients of heart, liver, spleen, kidney and testicles among the 4 groups at the 12 th week of the cessation of Mn-exposure in rats(P>0.05).CONCLUSION: Sub-chronic Mn exposure can impair learning and memory ability of rats, and the damage persists after the cessation of Mn-exposure.

Objective: To explore the improvement rate of liver fibrosis in patients with chronic hepatitis B virus infection who received entecavir alone or in combination with anluohuaxianwan for 78 weeks. Methods: Patients with chronic HBV infection were randomly treated with entecavir alone or in combination with anluohuaxian for 78 weeks. Ishak fibrosis score was used for blind interpretation of liver biopsy specimens. The improvement in liver fibrosis condition before and after the treatment was compared. Student's t test and non-parametric test (Mann-Whitney U-Test and Kruskal-Wallis test) were used to analyze the measurement data. The categorical variables were analyzed by Chi-square test method and Spearman’s rank correlation coefficient was used to test bivariate associations. Results: Liver fibrosis improvement rate after 78 weeks of treatment was 36.53% (80/219) and the progression rate was 23.29% (51/219). The improvement of liver fibrosis was associated to the degree of baseline fibrosis and treatment methods (P < 0.05). The improvement rate of hepatic fibrosis in patients treated with anluohuaxianwan combined with entecavir at baseline F < 3 (54.74%, 52/95) was significantly higher than that in patients treated only with entecavir (33.33%, 16/48), P = 0.016 and the progression rate of hepatic fibrosis (13.68%, 13/95) was lower than that in patients treated alone (18.75%, 9/48), P = 0.466. In patients with baseline F < 3, the proportion of patients with improved and stable liver fibrosis in the combined treatment group (68.1%, 32/47) was higher than that in the treatment group alone (51.7%, 15/29). Conclusion Combined anluohuaxianwan and entecavir treatment can significantly improve the improvement rate of liver fibrosis in patients with chronic hepatitis B virus infection. Furthermore, it has the tendency to improve the stability rate and reduce the rate of progression of liver fibrosis.

Objective: To study the correlation between the level of T-bet expression and liver damage in peripheral plasma cells of patients with autoimmune hepatitis (AIH) in order to provide reference for the study of pathogenesis and development of diseases. Methods: The peripheral venous blood and clinical examination data of 29 cases with AIH and 6 healthy volunteers were collected. The percentage of subpopulations of peripheral blood B cells and the proportion of T-bet⁺ cells in each subgroup were detected by flow cytometry. Plasma cells (CD19⁺CD10^-CD27^hiCD38^hi), primary B cells (CD19⁺CD10^-CD27^-IgD⁺), transitional B cells (CD19⁺CD10⁺), and memory B cells (CD19⁺CD10^-CD27⁺IgD^-) were the included subsets of B cells. Serum immunoglobulin G (IgG) and alanine aminotransferase (ALT) levels, the proportion of B cells in peripheral blood subsets and IgG level, the proportion of T-bet⁺ cells in each subset and the proportion of T-bet⁺ plasma cells in each subset in B cells, the proportion of T-bet⁺ plasma cells and the level of serum ALT were analyzed for correlation analysis. Statistical analysis was performed using two independent sample t-tests and linear regression. Results: The serum IgG level of AIH patients with abnormal ALT (19.47 ± 1.039)g/L was significantly higher than that of normal ALT patients (15.5 ± 1.069)g/L, and the difference was statistically significant (t = 2.65, P < 0.05). The percentage of peripheral plasma cells in B cells of AIH patients (2.80 ± 0.14) % was higher than that of healthy volunteers (0.73 ± 0.09) %, and the difference was statistically significant (P < 0.01). The percentage of T-bet⁺ cells in peripheral plasma cells of AIH patients (23.54 ± 1.61) % was higher than that of healthy volunteers (6.59±0.59) % , and the difference was statistically significant (P < 0.01). The correlation analysis showed that the proportion of T-bet⁺ cells in peripheral plasma cells of AIH patients was positively correlated with the proportion of plasma cells to B cells (r = 0.224 7, P < 0.01), and the percentage of peripheral plasma cells to B cells was positively correlated with the level of serum IgG (r = 0.299 1, P < 0.01). Serum IgG level was correlated with the level of ALT, reflecting an indicator of liver damage (t = 2.65, P < 0.05). Conclusion The increase of T-bet expression in the peripheral plasma cells of AIH patients is associated with liver damage, which is a new mechanism of AIH pathogenesis and disease progression.

Objective: To investigate the clinical effect and safety of long-acting pegylated interferon-α-2b (Peg-IFN-α-2b) (Y shape, 40 kD) injection (180 μg/week) in the treatment of HBeAg-positive chronic hepatitis B (CHB) patients, with standard-dose Peg-IFN-α-2a as positive control. Methods: This study was a multicenter, randomized, open-label, and positive-controlled phase III clinical trial. Eligible HBeAg-positive CHB patients were screened out and randomized to Peg-IFN-α-2b (Y shape, 40 kD) trial group and Peg-IFN-α-2a control group at a ratio of 2:1. The course of treatment was 48 weeks and the patients were followed up for 24 weeks after drug withdrawal. Plasma samples were collected at screening, baseline, and 12, 24, 36, 48, 60, and 72 weeks for centralized detection. COBAS® Ampliprep/COBAS® TaqMan® HBV Test was used to measure HBV DNA level by quantitative real-time PCR. Electrochemiluminescence immunoassay with Elecsys kit was used to measure HBV markers (HBsAg, anti-HBs, HBeAg, anti-HBe). Adverse events were recorded in detail. The primary outcome measure was HBeAg seroconversion rate after the 24-week follow-up, and non-inferiority was also tested. The difference in HBeAg seroconversion rate after treatment between the trial group and the control group and two-sided confidence interval (CI) were calculated, and non-inferiority was demonstrated if the lower limit of 95% CI was > -10%. The t-test, chi-square test, or rank sum test was used according to the types and features of data. Results: A total of 855 HBeAg-positive CHB patients were enrolled and 820 of them received treatment (538 in the trial group and 282 in the control group). The data of the full analysis set showed that HBeAg seroconversion rate at week 72 was 27.32% in the trial group and 22.70% in the control group with a rate difference of 4.63% (95% CI -1.54% to 10.80%, P = 0.1493). The data of the per-protocol set showed that HBeAg seroconversion rate at week 72 was 30.75% in the trial group and 27.14% in the control group with a rate difference of 3.61% (95% CI -3.87% to 11.09%, P = 0.3436). 95% CI met the non-inferiority criteria, and the trial group was non-inferior to the control group. The two groups had similar incidence rates of adverse events, serious adverse events, and common adverse events. Conclusion In Peg-IFN-α regimen for HBeAg-positive CHB patients, the new drug Peg-IFN-α-2b (Y shape, 40 kD) has comparable effect and safety to the control drug Peg-IFN-α-2a.

Objective To establish an auto-control system for high-throughput and multi-channel DNA synthesis which can simultaneously and quickly synthesize up to 96 different oligonucleotides in a 96-well microtiter format.Methods The PLC and its extended modules is used as the main-control unit, which executes the DNA automatic synthesis process according to the synthesis sequences and steps set by the user,and the manual injecting reagent etc.And the configuration software and VC6.0 were used for programming the man-machine interface sofeware to set synthesis parameters, position calibration,flux calibration data etc, and communicated with PLC.Results The synthesis application of about 150 000 DNA chains has proved that the synthesis cycle time for 96 couplings was 4 min,the average coupling efficiency was 99%across the entire 96-well plate,the monomer reagent usage was reduced by 50 percent,and the synthesis configuration was more flexible.Conclusion A reliable and simple auto-control system is provided for parallel synthesis of 96-channel oligonucleotide chains,which can meet the demands of high-throughput and multi-channel DNA synthesis.