Objective To investigate the mechanism of mikanolide derivative LY19380b in inhibiting the growth of human leukemia cell HEL.Methods Methyl thiazolyl tetrazolium(MTT)assay was used to detect the effect of compound LY19380b on the proliferation of human tumor cells,flow cytometry was used to determine cell cycle,Annexin V-FITC/PI double staining and Hoechst 33258 staining were used to determine apoptosis.Western blot was used to analyze effects of LY19380b on cell cycle and apoptosis-related proteins.Results LY19380b had anti-proliferative activity on different human tumor cells,and significantly inhibited the growth of human leukemia cell HEL.It can also induce apoptosis and affect the cell cycle of HEL.In addition,LY19380b could significantly increase the expressions of P53,BIM,BID,BAD,BAX,FLIP,P21 and Cyclin B1 proteins,while decreased the expressions of Bcl-2,p-CDC25C,p-AKT,p-STAT3 and p-ERK proteins.Conclusion By increasing the expressions of pro-apoptotic proteins BIM,BID,BAD and BAX,decreasing the expression of anti-apoptotic protein Bcl-2,LY19380b induced the apoptosis of human leukemia cell HEL,and upregulated the expressions of P21 and Cyclin B1,thus leading to cell cycle arrest in HEL.

Objective:To construct a novel dual-specific antibody targeting human CD123 (CD123 DuAb) and study its effects in acute myeloid leukemia (AML) .Methods:Based on the variable region of the CD123 monoclonal antibody independently developed at our institution, the CD123 DuAb expression plasmid was constructed by molecular cloning and transfected into ExpiCHO-S cells to prepare the antibody protein. Through a series of in vitro experiments, its activation and proliferation effect on T cells, as well as the effect of promoting T-cell killing of AML cells, were verified.Results:① A novel CD123 DuAb plasmid targeting CD123 was successfully constructed and expressed in the Expi-CHO eukaryotic system. ②The CD123 DuAb could bind both CD3 on T cells and CD123 on CD123 + tumor cells. ③When T cells were co-cultured with MV4-11 cells with addition of the CD123 DuAb at a concentration of 1 nmol/L, the positive expression rates of CD69 and CD25 on T cells were 68.0% and 44.3%, respectively, which were significantly higher than those of the control group ( P<0.05). ④Co-culture with CD123 DuAb at 1 nmol/L promoted T-cell proliferation, and the absolute T-cell count increased from 5×10 5/ml to 3.2×10 6/ml on day 9, and CFSE fluorescence intensity decreased significantly. ⑤ With the increase in CD123 DuAb concentration in the culture system, T-cell exhaustion and apoptosis increased. When the CD123 DuAb was added at a concentration of 1 nmol/L to the culture system, the proportion of CD8 + PD-1 + LAG-3 + T cells was 10.90%, and the proportion of propidium iodide (PI) - Annexin Ⅴ + T cells and PI + Annexin Ⅴ + T cells was 18.27% and 11.43%, respectively, which were significantly higher than those in the control group ( P<0.05). ⑥ The CD123 DuAb significantly activated T cells, and the activation intensity was positively correlated with its concentration. The expression rate of CD107a on T cells reached 16.05% with 1 nmol/L CD123 DuAb, which was significantly higher than that of the control group ( P<0.05). ⑦The CD123 DuAb promoted cytokine secretion by T cells at a concentration of 1 nmol/L, and the concentration of IFN-γ and TNF-α in the supernatant of the co-culture system reached 193.8 pg/ml and 169.8 pg/ml, respectively, which was significantly higher than that of the control group ( P<0.05). ⑧When CD123 DuAb was added at a concentration of 1 nmol/L to the co-culture system of T cells and CD123 + tumor cells, the killing intensity of T cells significantly increased, and the residual rates of CD123 + MV4-11 cells, CD123 + Molm13 cells, and CD123 + THP-1 cells were 7.4%, 6.7%, and 14.6% on day 3, respectively, which were significantly lower than those in the control group ( P<0.05) . Conclusion:In this study, a novel CD123 DuAb was constructed and expressed. In vitro experiments verified that the DuAb binds to CD123 + tumor cells and T cells simultaneously, promotes T-cell activation and proliferation, and facilitates their anti-leukemia effect, which provides a basis for further clinical research.

Objective:To construct a novel chimeric antigen receptor T (CAR-T) cell targeting CD138 and to investigate its cytotoxicity against myeloma cells.Methods:The hybridoma strain that can stably secrete the CD138 monoclonal antibody (mAb) was prepared and obtained through monoclonal antibody screening technology. The hybridoma strain cells were intraperitoneally injected into mice to produce ascites containing monoclonal antibodies, which were then collected and purified to obtain pure CD138 mAb. Further examinations were performed to assess the biological characteristics of CD138 mAb. The variable region sequence of this antibody was amplified through reverse transcription polymerase chain reaction and was used as the antigen recognition domain of CD138 CAR, which was subsequently expressed on the surface of T cells by lentiviral infection. Flow cytometry was employed to assess the phenotype of CD138 CAR-T cells. In vitro cytotoxicity and degranulation assays were performed to evaluate their antitumor effects.Results:① We successfully prepared anti-human CD138 antibody hybridoma cell lines and screened a hybridoma cell strain, 5G2, which could persistently and stably secrete the anti-CD138 antibody. ② The purified CD138 (5G2) mAb can especially recognize CD138 + cells with a binding affinity constant (K D) of 6.011×10 -9 mol/L and showed no significant binding activity with CD138 - cells. ③The variable region sequence of the CD138 (5G2) antibody was obtained using molecular cloning technology, and CD138 (5G2) CAR was successfully constructed and expressed on T cells through lentivirus infection and, concurrently, demonstrated effective binding to recombinant human CD138 protein.④ The proliferation of T cells transduced with the CD138 (5G2) CAR was highly efficient. The phenotype analysis revealed that CD138 (5G2) CAR-T cells exhibited a greater tendency to differentiate into central memory T cells and memory stem T cells, with a reduced proportion of terminally differentiated effector memory subsets. ⑤CD138 (5G2) CAR-T cells demonstrated specific cytotoxicity against CD138 + myeloma cell line H929, whereas CD138 - cell line K562 remained unaffected. The percentage of residual H929 cells was (12.92±8.02) % after co-culturing with CD138 (5G2) CAR-T cells, while (54.25±15.79) % was left in the Vector-T group (E∶T=1∶2; P<0.001). ⑥Results of degranulation assays demonstrated a significant activation of CD138 (5G2) CAR-T cells after co-culture with the H929 cell line, whereas no significant activation was observed in Vector-T cells [ (25.78±3.35) % vs (6.13±1.30) %, P<0.001]. ⑦After co-culturing with CD138 + cells, CD138 (5G2) CAR-T cells exhibited a significant increase in cytokine secretion compared to the Vector-T group [interleukin-2: (1 697.52±599.05) pg/ml vs (5.07±1.17) pg/ml, P<0.001; interferon-γ: (3 312.20±486.38) pg/ml vs (9.28±1.46) pg/ml, P<0.001; and tumor necrosis factor-α: (1 837.43±640.49) pg/ml vs (8.75±1.65) pg/ml, P<0.001]. However, no significant difference was observed in cytokine secretion levels between the two groups after co-culturing with CD138 - cells. Conclusion:This study successfully prepared a novel monoclonal antibody against CD138, and CAR-T cells constructed with the antigen recognition domain derived from this 5G2 mAb demonstrated effective antitumor activity against myeloma cells. This can be used as a new option for the detection of the CD138 antigen and proposes a novel strategy for multiple myeloma immunotherapy.

AIM:To establish and evaluate a colonoids model of intestinal barrier dysfunction with irritable bowel syndrome(IBS).METHODS:The colonic recess of 20～22 g male C57BL/6 mice were isolated and cultured in ma-trix glue to proliferate and differentiate into 3D hollow spheres with colonic epithelioid structure.The following experi-ments were carried out:(1)Colonoids and colonic tissues of mice were detected by immunofluorescence to identify colo-noids.(2)Fluorescein isothiocyanate dextran 4(FD4)evaluated the epithelial barrier function of colonoids.(3)To ex-plore the changes in the epithelial barrier of colonoids induced by interferon-γ(IFN-γ)at different concentrations and time points.FD4 and HE staining were used to evaluate the barrier function.RT-qPCR was used to detect the mRNA expres-sion of occludin and zonula occludens-1(ZO-1)in tight junctions of colonoids.Immunofluorescence was used to detect the distribution and localization of occludin and ZO-1 proteins.RESULTS:(1)The expression of EdU proliferation and in-testinal epithelial cell lineage markers in colonoids was consistent with that in mouse colonic tissues.(2)In the control group,FD4 did not infiltrate the colonoids lumen,but FD4 significantly infiltrated the colonoids lumen induced by ethyl-ene glycol-bis(β-aminoethyl ether)-N,N,N',N'-tetraacetic acid(EGTA).(3)From 18 h,the IFN-γ at 60,100,200 and 240 ng/mL could significantly infiltrate into the cavity of colonoids(0.033,0.032,0.042 and 0.001),and the barri-er injury of colonoids could be seen by HE staining.After 18 h,all concentrations of IFN-γ could significantly decrease the mRNA expression of occludin and ZO-1,and the fluorescence of occludin and ZO-1 decreased significantly(P<0.05).CONCLUSION:(1)The cultured organoids are colonoids with complete epithelial barrier.(2)IFN-γ could in-duce the decrease of the transcriptional levels of occludin and ZO-1 in the tight junction of colonoids,the decrease of the expression of corresponding proteins,and the change of localization and distribution,thus increasing the epithelial perme-ability of colonoids.This model is highly consistent with the pathophysiological state of IBS colonic mucosal barrier dys-function,which provides a new tool and method for studying the direction of colonic mucosal barrier dysfunction in IBS.

AIM:To investigate the influence of fat mass and obesity-associated(Fto)gene on the aberrant contraction of aortic smooth muscle in diabetes mellitus(DM)mice,and to explore the mechanism of Fto gene underlying the calcium regulation.METHODS:Smooth muscle-specific Fto gene knockout(FtoSMKO)mice were generated using Cre-loxP technology.The experiment involved 3 groups of mice:wild-type(WT)group,DM model group and FtoSMKO-DM group,with 15 mice in each group.In DM group and FtoSMKO-DM group,type 1 DM was induced by intraperitoneal injec-tion of streptozotocin.The mice in WT group were injected with equal volume of citric acid-sodium citrate buffer solution.The influences of different drugs on the contraction responses of aortic smooth muscle in mice were analyzed using a multi-myograph system.The expression level of FTO protein in the aortic tissues was detected by Western blot.RESULTS:(1)Compared with WT mice,the expression levels of FTO protein in the aortic tissues of DM mice were significantly in-creased(P＜0.01).(2)The expression level of FTO protein in smooth muscle was significantly decreased after knockout of Fto gene(P＜0.01).Compared with WT group,the mice in DM group exhibited a significant decrease in body weight and a marked increase in fasting blood glucose level(P＜0.05).There were no noticeable differences in body weight or fasting blood glucose level between FtoSMKO-DM group and DM group(P＞0.05).(3)The contraction responses of aortic smooth muscle in DM group were substantially increased by phenylephrine compared with WT group.Specifically,vaso-constriction responses mediated by non-L-type calcium channels and store-operated calcium channels(SOCC)were signifi-cantly enhanced in DM group.In addition,the responses mediated by inositol 1,4,5-trisphosphate receptors(IP3R),which facilitate calcium release from the sarcoplasmic reticulum,were significantly enhanced.However,the responses mediated by caffeine-activated ryanodine receptors(RyR),which also facilitate calcium release from the sarcoplasmic re-ticulum,were significantly inhibited(P＜0.05).(4)Compared with DM group,the phenylephrine-induced contraction re-sponses of aortic smooth muscle in FtoSMKO-DM group were greatly weakened(P＜0.05).In particular,the vasoconstriction responses mediated by non-L-type calcium channels and SOCC in FtoSMKO-DM group were greatly suppressed(P＜0.05),while those mediated by caffeine-activated RyR were dramatically boosted(P＜0.05).However,IP3R-mediated responses were not affected(P＞0.05).CONCLUSION:Smooth muscle-specific Fto gene knockout suppresses contractile hyperre-sponsiveness in the aortic smooth muscle of DM mice,which may be attributed to involvement of FTO protein in calcium regulation in the vascular smooth muscle.

Objective To explore the characteristics of blood vitamins A, B2, B6, B12, D, E, K1, K2 and folic acid and their correlation with severity in patients with metabolic-related fatty liver disease (MAFLD). Methods　From September to December 2022, a total of 473 cases of residents were recruited through community MAFLD screening activities and their health information was obtained through questionnaire survey and physical examination. The severity of hepatic steatosis was determined with FibroScan, and vitamin concentrations were determined with liquid chromatography-tandem mass spectrometry. Two independent samples' t-tests were used to assess the differences between the two groups, and univariate chi-square tests and multivariate logistic regression analysis were used to explore the related factors of MAFLD. Results　Of the 473 inhabitants, 195 (41.23%, 195/473) met the diagnostic criteria for MAFLD, including mild 43 (22.05%, 43/195) cases of fatty liver, 88 (45.13%, 88/195) cases of moderate fatty liver, and 64 (32.82%, 64/195) cases of severe fatty liver. Using healthy residents collected during the same period as controls, the overall mean of vitamins A, E, K1, and K2 in the MAFLD group was higher than that of the healthy group, with a statistical difference (P<0.05). Furthermore, the concentrations of vitamins A, E, K1 and K2 increased with the severity of fatty liver [R=0.149, P=0.004; R=0.245, P<0.001; R=0.110, P=0.032; R=0.129，P=0.012]. There were statistically significant differences (P<0.05) in the blood levels of vitamin A and E between patients with moderate or severe fatty liver and the healthy population. The blood vitamins K1 and K2 in severe fatty liver patients were also different from those of healthy people (P<0.05). However, there was no significance between folic acid, vitamin D, B2, B6, B12, and MAFLD (P>0.05). Through univariate chi-square analysis and multivariate logistic regression analysis, it was found that male [Wald=5.789, P=0.034，OR=1.598(1.037-2.463)] and vitamin E≥8.13 μg/mL[Wald=14.632，P<0.001，OR=2.378(1.522-3.674)] were risk factors for moderate and severe MAFLD. Conclusions The concentrations of vitamin A, E, and K in the blood are increased in patients with MAFLD compared to the healthy population, and they are positively correlated with the severity of MAFLD. ale gender and high levels of vitamin E may be related to moderate to severe MAFLD.

AIM:To investigate the mechanism of Piezo1 channel activation promoting the increase in intra-cellular Ca2+ concentration([Ca2+]i)of rat coronary artery smooth muscle cells(CASMCs).METHODS:The primary CASMCs of SD rats were cultured,and the expression and subcellular localization of Piezo1 in the cells were observed by immunofluorescence staining.The Piezo1 and stromal interaction molecule 1(STIM1)in CASMCs were knocked down by siRNA transfection,and the expression levels of the proteins were detected by Western blot.Utilizing laser confocal mi-croscopy,the change of[Ca2+]i in CASMCs was detected by Fluo-4 AM fluorescent probes.RESULTS:It was confirmed by immunofluorescence staining that the expression of Piezo1 existed in primary rat CASMCs.Immunofluorescence staining also showed that Piezo1 was co-located with sarco-/endoplasmic reticulum Ca2+-ATPase 2(SERCA2),mitochondrial outer membrane protein TOM20 and nuclear membrane protein lamin B1.Western blot results showed that the protein expres-sion levels of STIM1 and Piezo1 were significantly down-regulated by siRNA transfection(P<0.05).Compared with con-trol group,Yoda1,the agonist of Piezo1,could increase the extracellular Ca2+ influx of CASMCs(P<0.01).However,the Ca2+ influx mediated by Yoda1 was not affected by the inhibition of L-type calcium channels.Treatment with Yoda1 in-creased the intracellular Ca2+ release of CASMCs(P<0.01).However,inhibition of calcium channels on endoplasmic re-ticulum,ryanodine receptor and inositol 1,4,5-triphosphate receptor,did not affect intracellular Ca2+ release mediated by Yoda1.After the Ca2+ in endoplasmic reticulum was emptied using thapsigargin(TG),Yoda1 also mediated the Ca2+ re-lease of other organelles in CASMCs(P<0.01).After inhibition of L-type calcium channels,treatment with store-operated calcium channel(SOCC)inhibitor BTP2 or knockdown of STIM1 led to the decrease in extracellular Ca2+ influx of CASMCs mediated by Yoda1(P<0.01).Treatment with TG increased the release of Ca2+ from the endoplasmic reticulum of CASMCs after knockdown of Piezo1(P<0.05),but the extracellular Ca2+ influx mediated by TG was not affected.After inhibition of L-type calcium channels and SOCC,knockdown of Piezo1 led to the decreases in intracellular Ca2+ release and extracellular Ca2+ influx induced by Yoda1(P<0.01).CONCLUSION:The Piezo1 agonist orchestrates the influx of extracellular Ca2+ by activating Piezo1 channels on the cell membrane and inducing the indirect activation of SOCC.More-over,it facilitates the release of Ca2+ from organelles.Consequently,these pathways synergistically elevate the[Ca2+]i of rat CASMCs.

Objective:To explore the repair effect of resveratrol combined with Schwann cell-like cells(SCLCs)dif-ferentiated from adipose-derived stem cells(ADSCs)on sciatic nerve injury in rats.Methods:ADSCs were primarily cultured and induced to differentiate into SCLCs.Cell morphology was observed by scanning electron microscopy.West-ern Blot method was used to detect the expressions of S100 calcium-binding protein β(S100β),p75 neurotrophin receptor(p75NTR),and glial fibrillary acidic protein(GFAP).Rats were randomly divided into Control group(Con-trol),Schwann cell-like cell group(SCLCs),resveratrol group(Res),and resveratrol+Schwann cell-like cell group(Res+SCLCs).Eight weeks after the successful establishment of the sciatic nerve injury model,the sciatic nerve func-tion index(SFI)of each group was detected by footprint experiment;the mechanical withdrawal threshold(MWT)was measured by von Frey filament stimulation needle;The wet weight ratio(WR)of the tibialis anterior muscle was deter-mined by weighing method;Western Blot and RT-qPCR methods were used to detect the expressions of neurotrophin-3(NT-3),nerve growth factor(NGF),insulin-like growth factor-1(IGF-1),and brain-derived neurotrophic factor(BDNF)at the injury site.Results:After 8 days of induction of ADSCs,the cells had elongated poles and increased extracellular components;S100β,p75NTR,and GFAP proteins were highly expressed.After treatment with SCLCs,Res,and Res+SCLCs,the SFI and WR of the treatment groups were significantly better than those of the Control group(P＜0.05);the MWT of rats in the Res+SCLCs group and SCLCs group was reduced(P＜0.05).Western Blot re-sults showed that the expressions of NT-3,IGF-1,NGF,and BDNF proteins in rats in the Res+SCLCs group were higher than those in other groups(P＜0.05);The expressions of NT-3,NGF,and BDNF proteins in rats in the SCLCs group were higher than those in the Control group(P＜0.05);the expressions of NT-3 and NGF proteins in rats in the Res group were higher than those in the Control group(P＜0.05).RT-qPCR results showed that the expressions of NT-3,IGF-1,NGF,and BDNF mRNA in rats in the Res+SCLCs group were highly expressed;the expressions of NT-3,IGF-1,NGF,and BDNF mRNA in rats in the SCLCs group were higher than those in the Control group(P＜0.05);The expressions of IGF-1 and NGF mRNA in rats in the Res group were higher than those in the Control group(P＜0.05).Conclusion:Res combined with SCLCs differentiated from ADSCs has a good repair effect on sciatic nerve inju-ry in rats.

Yellowish sweating disease is one of the fluid-retention diseases recorded in Jin Gui Yao Lve(Synopsis of the Golden Cabinet).The symptoms of yellowish sweating disease are complex,involving multiple visceral lesions,which are caused by interior heat and exterior deficiency,together with the concurrent invasion of pathogens of wind and water.Huangqi Shaoyao Guizhi Kujiu Decoction(mainly composed of Astragali Radix,Paeoniae Radix Alba,Cinnamomi Ramulus and vinegar)and Guizhi Plus Huangqi Decoction(mainly composed of Cinnamomi Ramulus and Astragali Radix)are the classical formula for the treatment of yellowish sweating disease.Both of the formulas have the actions of warming defensive qi and dredging yang,removing fluid retention and resolving dampness.Usually suffering heat in the spleen and stomach,together with carelessness in daily living and wind-water pathogens attacking the exterior,contributes to the key pathogenesis of diabetes mellitus.The clinical manifestations,etiology,occurrence and progression,and prognosis of yellowish sweating disease are similar to those of diabetic complications.Therefore,the treatment of diabetes complications such as diabetic kidney disease,diabetic cardiomyopathy,diabetic peripheral neuropathy,diabetes mellitus complicated with liver dysfunction,diabetic foot,and diabetic retinopathy can follow the therapeutic principles of yellowish sweating disease,and can be achieved by the therapies of clearing heat and purging fire,dispelling cold and removing dampness,and nourishing nutritive yin and harmonizing defensive qi with the appropriate formulas.The exploration of the treatment of diabetes mellitus and its complications from the pathogenesis and symptom characteristics of yellowish sweating disease will expand the thoughts for treating diabetic complications with traditional Chinese medicine.

The global COVID-19 coronavirus pandemic has infected over 109 million people, leading to over 2 million deaths up to date and still lacking of effective drugs for patient treatment. Here, we screened about 1.8 million small molecules against the main protease (M^pro) and papain like protease (PL^pro), two major proteases in severe acute respiratory syndrome-coronavirus 2 genome, and identified 1851M^pro inhibitors and 205 PL^pro inhibitors with low nmol/l activity of the best hits. Among these inhibitors, eight small molecules showed dual inhibition effects on both M^pro and PL^pro, exhibiting potential as better candidates for COVID-19 treatment. The best inhibitors of each protease were tested in antiviral assay, with over 40% of M^pro inhibitors and over 20% of PL^pro inhibitors showing high potency in viral inhibition with low cytotoxicity. The X-ray crystal structure of SARS-CoV-2 M^pro in complex with its potent inhibitor 4a was determined at 1.8 Å resolution. Together with docking assays, our results provide a comprehensive resource for future research on anti-SARS-CoV-2 drug development.
Humans ; Antiviral Agents/chemistry* ; COVID-19 ; COVID-19 Drug Treatment ; High-Throughput Screening Assays ; Molecular Docking Simulation ; Protease Inhibitors/chemistry* ; SARS-CoV-2/enzymology* ; Viral Nonstructural Proteins