Total Chemical Synthesis of Correctly Folded Disulfide-Rich Proteins Using a Removable O-Linked ß-N-Acetylglucosamine Strategy.

Disulfide-rich proteins are useful as drugs or tool molecules in biomedical studies, but their synthesis is complicated by the difficulties associated with their folding. Here, we describe a removable glycosylation modification (RGM) strategy that expedites the chemical synthesis of correctly folded proteins with multiple or even interchain disulfide bonds. Our strategy comprises the introduction of simple O-linked ß-N-acetylglucosamine (O-GlcNAc) groups at the Ser/Thr sites that effectively improve the folding of disulfide-rich proteins by stabilization of their folding intermediates. After folding, the O-GlcNAc groups can be efficiently removed using O-GlcNAcase (OGA) to afford the correctly folded proteins. Using this strategy, we completed the synthesis of correctly folded hepcidin, an iron-regulating hormone bearing four pairs of disulfide-bonds, and the first total synthesis of correctly folded interleukin-5 (IL-5), a 26 kDa homodimer cytokine responsible for eosinophil growth and differentiation.

Elaborated Reaction Pathway of Photothermal Catalytic CO2 Conversion with H2 O on Gallium Oxide-Decorated and -Defective Surfaces.

Ga2 O3 -decorated and -defective surface models based on anatase TiO2 have been established. The thermodynamic reaction pathways, including protonation, deoxygenation and hydroxylation steps, during CO2 conversion with H2 O to C1 products were calculated. The calculation results demonstrate that a Ga2 O3 cocatalyst enhances the selective adsorption of CO2 and slightly weakens the competitive adsorption of H2 O. The promotion effect of Ga2 O3 on the subsequent reaction depends on the availability of protons and electrons. Free-energy calculations revealed that the basic functional site generated by Ga2 O3 not only suppresses the back reaction of the OH group after H2 O directly provides protons but also maintains the surface defect oxygen vacancy (VO ), which promotes the reaction thermodynamics but tends to be consumed in the process. Additionally, Ga2 O3 decoration promotes VO formation, and the coexistence of Ga2 O3 and VO further decreases the reaction rate-determining step energy barrier, promoting C1 production.

Cytokine release syndrome and relevant factors of CD19 targeted chimeric antigen receptor T cell therapy in relapsed/refractory B cell hematological malignancies.

OBJECTIVES AND METHODS: We reviewed the outcomes of 77 episodes of CD19 CAR-T therapy in 67 patients with B cell hematological malignancies from October 2016 to January 2020. Factors related to the grade of cytokine release syndrome (CRS) were explored by multivariate analysis, nonparametric test was conducted to explore the correlation between CRS and response. Kaplan-Meier curves were used to indicate survival profiles, and the correlation between CRS and survival was determined by the log-rank test. RESULTS: The rate of complete remission (CR) was 74.0% (57/77). CRS of any grade occurred in 68 of 77 episodes (grade 1: 32.5%, grade 2: 24.7%, grade 3: 22.1%, grade 4: 6.5%, grade 5: 2.6%). Patients with a history of transplantation had less severe CRS, and dose escalation-based infusion reduced the severity of CRS. Severe CRS was related to a higher CR rate but had no significant impact on event-free survival (EFS), relapse-free survival (RFS), or overall survival (OS). CONCLUSION: As a common adverse reaction of CAR-T therapy, the severity of CRS can be alleviated by dose escalation infusion, a history of transplantation was correlated with less severe CRS. Severe CRS was related to better response but was unrelated to long-term survival.

Effective Management of Polycythemia Vera With Ropeginterferon Alfa-2b Treatment.

Background: Polycythemia vera (PV) is a myeloproliferative neoplasm. Ropeginterferon alfa-2b is a new-generation polyethylene glycol-conjugated proline-interferon. It is approved for the treatment of PV at a starting dose of 100 µg (50 µg for patients receiving hydroxyurea (HU)) and dose titrations up to 500 µg by 50 µg increments. The study was aimed at assessing its efficacy and safety at a higher starting dose and simpler intra-patient dose escalation. Methods: Forty-nine patients with PV having HU intolerance from major hospitals in China were treated biweekly with an initial dose of 250 µg, followed by 350 µg and 500 µg thereafter if tolerated. Complete hematological response (CHR) was assessed every 12 weeks based on the European LeukemiaNet criteria. The primary endpoint was the CHR rate at week 24. The secondary endpoints included CHR rates at weeks 12, 36 and 52, changes of JAK2V617F allelic burden, time to first CHR, and safety assessments. Results: The CHR rates were 61.2%, 69.4% and 71.4% at weeks 24, 36, and 52, respectively. Mean allele burden of the driver mutation JAK2V617F declined from 58.5% at baseline to 30.1% at 52 weeks. Both CHR and JAK2V617F allele burden reduction showed consistent increases over the 52 weeks of the treatment. Twenty-nine patients (63.0%) achieved partial molecular response (PMR) and two achieved complete molecular response (CMR). The time to CHR was rapid and median time was 5.6 months according to central lab results. The CHRs were durable and median CHR duration time was not reached at week 52. Mean spleen index reduced from 55.6 cm2 at baseline to 50.2 cm2 at week 52. Adverse events (AEs) were mostly mild or moderate. Most common AEs were reversible alanine aminotransferase and aspartate aminotransferase increases, which were not associated with significant elevations in bilirubin levels or jaundice. There were no grade 4 or 5 AEs. Grade 3 AEs were reversible and manageable. Only one AE led to discontinuation. No incidence of thromboembolic events was observed. Conclusion: The 250-350-500 µg dosing regimen was well tolerated and effectively induced CHR and MR and managed spleen size increase. Our findings demonstrate that ropeginterferon alfa-2b at this dosing regimen can provide an effective management of PV and support using this dosing regimen as a treatment option.

[Clinical Research of Dendritic Cell-Mediated Tumor-Associated Antigen-Specific Cytotoxic T Lymphocytes in the Treatment of Multiple Myeloma and Non-Hodgkin Lymphoma].

OBJECTIVE: To investigate the safety and efficacy of tumor-associated antigen-specific cytotoxic T lympho- cytes (TAA-CTL) in the treatment of multiple myeloma (MM) and non-Hodgkin lymphoma (NHL). METHODS: Peripheral blood mononuclear cells (PBMNC)of patients were collected. Dendritic cells (DC) were loaded with multiple tumor-associated antigens (TAA) (NY-ESO-1, MAGE-A3, MAGE-A4, WT1, Survivin, PRAME, LMP1 and LMP2A), then co-cultured with PBMNC to induce cytotoxic T lymphocytes (CTL). The phenotypes of cell products were detected, and the disease statuse was evaluated in 7 patients during or after infusion. The changes of TAA-CTL amount in the PBMNC of patients were measured by using IFN-γ ELISpot assay. RESULTS: TAA-CTL products were generated comprising CD3+ T cells (mean 82.98%) with a mixture of CD4+ (mean 42.09%) and CD8+ (mean 25.32%) T cells. Among them, 70% expressed effectors memory markers (CD45RO+CD62L-CCR7-). Each patient received TAA-CTL infusions for 1-4 times, and none of them showed obvious adverse reactions. The clinical symptoms and laboratory or imaging examination of 5 patients achieved positive effects. After cell therapy, the spot-forming cells (SFC) levels of most patients gradually increased and the peak often appeared about 2-3 weeks after the infusion. CONCLUSION: TAA-CTLs preliminarily show its safety and efficacy in MM and NHL patients, however, a larger population sample is needed to explore its clinical application value.

[Efficacy Analysis of Unrelated Cord Blood Transplantation for High-Risk Refractory AML1-ETO Positive Myeloid Leukemia].

OBJECTIVE: To analyze the clinical outcomes of engraftment, graft-versus-host disease (GVHD) and survival in the patients with AML1-ETO positive acute myeloid leukemia (AML) treated with unrelated umbilical cord blood transplantation (UCBT). METHODS: Forty-Five patients with high-risk refractory AML1-ETO positive AML were treated with a single UCBT in a single center from July 2010 to April 2018. All the patients underwent a myeloablative preconditioning regimen，and cyclosporine A (CSA) combined with mycophenolate mofetil (MMF) was used to prevent GVHD. RESULTS: The median value of total nucleated cells (TNC) in cord blood was 5.21 (1.96-12.68)×107/kg recipient body weight, and that of CD34+ cells was 5.61 (0.56-15.4)×105/kg recipient weight. The implantation rate of neutrophil at 42 d and that of platelet at 120 d were 95.6% and 86.7%, respectively. The median time of absolute neutrophil count (ANC)＞0.5×109/L and platelet 20×109/L were 16 (12-18) d and 37 (17-140) d after transplantation, respectively. The cumulative incidence of Ⅰ -Ⅳ grade acute GVHD (aGVHD) at 100 d after transplantation was 48.9% (95% CI 33.5%-62.6%), Ⅱ-Ⅳ grade aGVHD occurred in 12 cases (33.3%) (95% CI 20%-47.2%) , and Ⅲ-Ⅳ grade a GVHD in 8 cases (20%) (95% CI 9.8% -32.8%). In 5 cases of 40 patients survived over 100 days, the chronic GVHD (cGVHD) occurred after transplantation, among which 4 were localized, and 1 was extensive. 3 patients relapsed, and the 2-year cumulative relapse rate was 9.5% (95% CI 2.4%-22.8%). The median follow-up time was 23.5 (0.9-89.67) months, 10 patients died, 2-year disease-free survival rate (DFS) was 72.7%, and overall survival rate (OS) was 75.5%. Multivariate analysis showed that Ⅲ-Ⅳ. acute GVHD (aGVHD) affected overall survival. CONCLUSION: UCBT is an effective rescue treatment for patients with high-risk refractory AML1-ETO positive AML.

Double vs. single cord blood transplantation in adolescent and adult hematological malignancies with heavier body weight (≥50†kg).

BACKGROUND: Double-unit cord blood transplantation (CBT) can be used to overcome the limitation of single-unit CBT with low cell content for adults and larger adolescents. However, whether double-unit CBT is superior to single-unit CBT remains controversial. METHODS: We reviewed the medical records of 228 consecutive hematological malignancies who received CBT between November 2005 and December 2013. Ninety-seven eligible patients met the criteria (age ≥14 years and body weight ≥50kg) and were enrolled in this study. RESULTS: The incidence of myeloid engraftment in the double-unit CBT group was significantly lower that in the single-unit CBT group (89.2 vs. 96.7%) (p = 0.026), and the incidence of platelet engraftment in the double-unit CBT group was slightly lower (70.3 vs. 86.7%) (p = 0.057). The 5-year transplant-related mortality rate was significantly higher in the double-unit CBT group when compared with that of the single-unit CBT group [54.1 vs. 33.3%, p = 0.026]. The 5-year probabilities of overall survival, disease-free survival and graft-versus-host disease (GVHD) -free/relapse-free survival in the double-unit CBT group were significantly lower than that of the single-unit CBT group (37.8 vs. 56.7%, p = 0.037; 32.4 vs. 55.0%, p = 0.017; 24.3 vs. 50.0%, p = 0.006). The incidences of GVHD and relapse were similar. CONCLUSIONS: For adolescent and adult hematological malignancies with heavier body weight (≥50kg), double-unit CBT has an inferior clinical outcome when compared with single-unit CBT having a sufficient cell dose. Double-unit CBT should only reserve for patients who need an urgent transplant but lacking of a related or unrelated donor and without an adequately dosed single CB.

[Early antigen diagnosis of invasive fungal infection in patients with hematological malignancies and patients receiving hematopoietic stem cell transplantation].

This study was purposed to evaluate the sensitivity and specificity of G/(1, 3-ß-D glucan)/GM (galactomannan) combined detection for early diagnosis of invasive fungal disease (IFD), determine the GM positive cut-off value, and investigate the change of diagnostic level before and after G/GM test and the relation of GM value with therapeutic effect. The ELISA with double antibody sandwich was used to detect the serum levels of G and G/M. The results showed that according to determined GM positive cut-off value, the sensitivity, specificity, positive and negative predictive value of G/GM combined detection were 100%, 65.7%, 67.6% and 100%, respectively. The case number of the clinical diagnosis of IFD increased from 1 to 24 cases, the diagnosis of 12 non-infective patients was changed as suspected IFD with the help of G/GM combined detection; the GM cut-off value decreased in patients whose GM cut-off value was higher before therapy and antifungal therapy was effective, while the GM cut-off value increased in patients no-responded to therapy. It is concluded that G/GM combined detection can increased the sensitivity of the diagnosis and reduce false negative rate in the early diagnosis of IFD. The dynamically monitoring G/GM cut-off value can be used as evaluation indicator of therapeutic efficacy.

[Functional defect of partial homing receptor on human cord blood hematopoietic stem/progenitor cells].

This study was aimed to investigate the function defect of partial homing receptor on cord blood hematopoietic stem cells (CBHSC) and explore efficacy and feasibility of intervention in vitro. The expression and activity of active groups in P, E-selectin ligands on CD34+ cells from cord blood, bone marrow and peripheral blood were detected by flow cytometry; meanwhile the expression of active groups in selectin ligands on CD34+ cells treated by fucosyl transferase in vitro was determined by flow cytometry. The results indicated that the expression levels of CD26 on the surface of stem/progenitor cells (CD34+) from cord blood, bone marrow and peripheral blood were (7.62+/-0.63)%, (6.35+/-0.89)% and (6.18+/-0.91)% (p>0.05) respectively. And the activities of CD26 of the three sources of stem cells were 67.15 U/1000 cells (1 U=1 pmol/min), 26.85 U/1000 cells and 20.95 U/1000 cells respectively, in which the activity of CD26 on surface of CD34+ from cord blood was significantly higher than that from other both sources (p<0.01). The expression levels of P-selectin ligand on the stem/progenitor cells three kinds were (83.46+/-6.33)%, (15.65+/-0.89)% and (80.17+/-6.85)%, and the expression levels of E-selectin ligand on stem/progenitor cells of three kinds were (25.31+/-1.03)%, (26.34+/-0.89)% and (29.79+/-1.78)% respectively. The expression of E-selectin ligand on the surface of cord blood stem/progenitor cell CD34+ increased from (25.31+/-1.03)% to (63.23+/-1.08)% after glycosylation engineering. It is concluded that there is no significant difference of the expression of CD26 between the three sources of stem/progenitor cells, but the activity of CD26 in cord blood was obviously higher than that in bone marrow and peripheral blood. The expression of P-selectin ligand on bone marrow stem/progenitor cell was lower than that on stem cells of cord blood and peripheral blood. Glycosylation engineering can promote and elevate the expression of E-selectin ligand on the surface of CD34+ cells from cord blood.