ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

Aim To investigate the effect of cinobufo-talin(CB)on the small ubiquitin-like modifier(SU-MO)modification of hypoxia inducible factor 1 alpha(HIF1α)on ferroptosis of gastric cancer cells.Meth-ods Human normal gastric mucosal epithelial cells(GES-1)and gastric cancer cells(MGC803)were treated with various concentrations of CB.MTT assay was employed to determine cell viability and calculate the IC50 value of CB in gastric cancer cells.Cell inva-sion was evaluated using Transwell assay.Cancer cells were subjected to treatment with ferroptosis agonists(erastin)or inhibitors(ferrostatin-1)to assess the levels of lipid reactive oxygen species(ROS),malon-dialdehyde(MDA),cell apoptosis,intracellular total iron,and Fe2+in gastric cancer cells.Western blot a-nalysis was conducted to detect the expression of SU-MO1 and HIF1α,while immunoprecipitation(IP)was utilized to investigate the interaction between SUMO1 and HIF1 α.An allograft tumor model was established and treated with CB or erastin to assess the impact of CB on tumor growth and ferroptosis in gastric cancer cells in vivo.Results CB at concentrations below 2μmol·L-1 had no impact on the viability of GES-1 cells.Compared to the control group,CB treatment dose-dependently inhibited the viability and invasion of MGC803 cells.CB treatment increased the levels of lipid reactive oxygen species(ROS),malondialdehyde(MDA),total iron,and Fe2+in gastric cancer cells,and promoted cell apoptosis(all P＜0.05),compared to the control group.The combination of CB and eras-tin enhanced ferroptosis,while ferrostatin-1 treatment suppressed CB-induced ferroptosis in gastric cancer cells.Mechanistically,CB inhibited the expression of SUMO1,reduced the SUMOylation of HIF1α,and consequently suppressed its expression.The ferroptosis induced by CB in gastric cancer cells could be reversed by overexpression of SUMO1.In vivo experiments con-firmed that CB inhibited tumor growth and induced fer-roptosis in gastric cancer cells.Conclusion CB in-duces ferroptosis in gastric cancer cells by inhibiting the SUMOylation modification of HIF1α.

Aim To investigate the intracellular up-take and target protein binding characteristics of two Bruton's tyrosine kinase inhibitors(BTKi)with differ-ent selectivities to provide further insights into the mechanisms of drug off-target-related bleeding risk.Methods Ibrutinib(non-selective BTKi)and za-nubrutinib(selective BTKi)were used as study drugs.After incubation of MEC-1 cells and human platelets with drugs,the cellular thermal shift assay(CETSA)was combined with Western blot to obtain the melting curve and isothermal curve to analyze the binding char-acteristics of the two drugs with the target protein BTK.After incubation of MEC-1 cells and human platelets with drugs,the concentrations of the two drugs were detected by liquid chromatography-tandem mass spectrometry(LC-MS/MS)to analyze the intracellular uptake of the two drugs.Results CETSA analysis confirmed that zanubrutinib was more selective for the target protein BTK compared to ibrutinib.LC-MS/MS analysis showed that both drugs were uptaken intracel-lularly by MEC-1 cells and platelets in a concentration-dependent manner.Conclusions While BTKi targe-ting BTK to B lymphocytes exerts therapeutic effects,off-target effects on platelets due to differences in their intracellular uptake,and target-binding characteristics may be one of the reasons for the differences in bleed-ing risk across selective BTKi.

Metastasis is the main risk factor for poor prognosis of laryngeal squamous cell carcinoma (LSCC) .Chemokines are closely related to metastasis in the tumor microenvironment.CXCL8 is a cyto-kine-like secreted protein that plays key roles in the malignant development of a variety of tumors,but has not been elucidated in LSCC.In this paper,we elucidated the role of CXCL8 in LSCC cells and found miRNAs that targeted CXCL8,which may become new targets for the diagnosis and treatment of LSCC.Firstly,the GEPIA showed that CXCL8 was highly expressed in head and neck cancer (P<0.05).The real-time fluorescence quantification (qRT-PCR) found that CXCL8 was highly expressed in LSCC cells.The enzyme-linked immunoassay also found that CXCL8 was highly secreted in the superna-tant of LSCC cells (P<0.001) .Then,the CCK8 assay confirmed that knockdown of CXCL8 significant-ly inhibited the proliferation of FD-LSC-1 and AMC-HN8 cells (the average inhibition rate was 34.0％and 19.5％,respectively);The EdU assay also confirmed that knockdown of CXCL8 significantly inhibi-ted the proliferation of LSCC cells (P<0.05) .The transwell assay confirmed that knockdown of CXCL8 also significantly inhibited the migration and invasion of FD-LSC-1 cell (average inhibition rate was 40.0％,38.5％,respectively);Knockdown of CXCL8 also significantly inhibited the migration and inva-sion of AMC-HN8 cell (average inhibition rate was 37.5％,53.5％,respectively ) .The analysis of bioinformatics predicted that CXCL8 may be a target of miR-513b-5p.The dual luciferase reporter assay confirmed that miR-513b-5p could bind to the CXCL8-3'UTR.QRT-PCR assay also confirmed that over-expression of miR-513b-5p could decrease the 60％ of the CXCL8 expression (P<0.01) .Cell function rescue assays found that overexpressed of CXCL8 could effectively reversed proliferation,migration and invasion of LSCC cells weakened by miR-513b-5p (P<0.05) .In summary,miR-513b-5p inhibited the proliferation,migration and invasion of LSCC cells by targeting CXCL8.

Objective:To investigate the value of immunoglobulin heavy chain(IgH)gene rearrangement in monitoring minimal residual disease(MRD)in multiple myeloma(MM)received autologous hematopoietic stem cell transplantation(auto-HSCT).Methods:The clinical data of 26 MM patients who received auto-HSCT in the Department of Hematology,Wuhan First Hospital from 2018 to 2022 were collected.IgH rearrangement was detected by multiplex PCR combined with capillary electrophoresis fragment analysis to evaluate minimal residual disease(MRD),and the outcome of the disease was analyzed statistically.Results:Among the 26 MM patients,18 were males and 8 were females,with a median age of 59(41-70)years.The median follow-up time after transplantation was 33(7-52)months.Compared with the IgH rearrangement negative group(n=17),the proportion of CR and sCR of patients with IgH rearrangement positive in bone marrow samples before auto-HSCT at 3 months after transplantation was lower(1/9 vs 14/17),and the duration of remission(DOR)after transplantation was shorter(10.78±4.35 vs 15.88±5.22 months),with statistically significant difference in DOR between the two groups(P＜0.05).Compared with IgH rearrangement negative group(n=21),the proportion of CR and sCR of patients with positive IgH rearrangement results from peripheral blood stem cell collection at 3 months after transplantation was lower(0/5 vs 15/21),the duration of remission(DOR)after transplantation was shorter(9.60±4.83 vs 15.19±5.11 months),and the difference in DOR between the two groups was statistically significant(P＜0.05).During the follow-up period,5 patients(5/9)with positive IgH rearrangement results in bone marrow specimens died,and all patients with negative IgH rearrangement results survived.Four patients(4/5)with positive IgH rearrangement results by peripheral blood stem cell samples died,while one patient(1/21)with negative IgH rearrangement results died.In both bone marrow and peripheral blood stem cell samples,the survival time of IgH rearrangement-positive patients after transplantation was shorter than that of IgH rearrangement-negative patients(P＜0.05).Logistic regression analysis showed that gender,disease stage,the proportion of bone marrow smear plasma cells at initial diagnosis,stem cell mobilization plan,efficacy evaluation before transplantation(≥ CR and＜CR),and CD34+cell count had no effect on IgH rearrangement results of stem cell collection(P＞0.05).Conclusion:By detecting IgH rearrangement of MM patients receiving auto-HSCT,the depth of MRD can be further evaluated,which has a certain guiding significance for the efficacy and prognosis of the disease.

Objective:To screen interleukin(IL)-1β secretion-related membrane transporters by macrophage experiment in vitro and conventional knockout mice.Methods:THP-1 cell line was differentiated to obtain human THP-1-derived macrophages,and the primary macrophages were obtained from human peripheral blood.FVB wild-type mice with the same sex and age were used as the controls of MRP1 knockout mice.The macrophages in abdominal cavity and bone marrow of mice were cultivated.The cells were treated with ABCC1/MRP1,ABCG2/BCRP,ABCB1/P-gp,OATP1B1,and MATE transporter inhibitors,then stimulated by lipopolysaccharide and adenosine triphosphate.The secretion level of IL-iβ was detected by ELISA,Western blot,and immunofluorescence.Results:After inhibiting ABCC1/MRP1 transporter,the secretion of IL-1β decreased significantly,while inhibition of the other 4 transporters had no effect.In animal experiment,the level of IL-1 β secreted by macrophages in bone marrow of MRP1 knockout mice was significantly lower than control group(P＜0.05).Conclusion:ABCC1/MRP1 transporter is a newly discovered IL-1β secretion pathway,which is expected to become a new target for solving clinical problems such as cytokine release syndrome.

Objective:To investigate the effect of genetic polymorphism of MTHFR C677T (rs1801133) on methotrexate (MTX) related toxicity in pediatric mature B-cell lymphoma patients. Methods:Fifty-eight intermediate and high risk patients under 18 years of age with mature B-cell lymphoma who received 5 g/m2 MTX (24 h intravenous infusion) in Sun Yat-sen University Cancer Center from August 2014 to December 2021 were included,and their toxicity of high-dose MTX (HD-MTX) were monitored and analyzed. Results:Among the 58 pediatric patients,the number of CC,CT,and TT genotypes for MTHFR C677T was 33,19 and 6,respectively. A total of 101 courses of HD-MTX therapy were counted,of which plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion were observed in 35 courses,≤0.2 μmol/L in 66 courses. Inter-group comparison showed that plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion increased the risk of developing oral mucositis (P<0.05). Compared with wild-type (CC genotype),patients in the mutant group (CT+TT genotype) were more likely to develop myelosuppression,manifested as anemia,leucopenia,neutropenia and thrombocytopenia. However,plasma MTX level at 48 h was not associated with MTHFR C677T gene polymorphism. Conclusion:The risk of developing oral mucositis in children with mature B-cell lymphoma is associated with plasma MTX concentration. Polymorphism of MTHFR C677T gene is not related to plasma MTX concentration in children with mature B-cell lymphoma,but is related to grade Ⅲ to Ⅳ hematological toxicity.

Objective:To evaluate the effect of different clear fluid fasting duration on the fluid responsiveness after anesthesia induction in pediatric patients with congenital heart disease.Methods:One hundred pediatric patients with congenital heart disease who underwent elective atrial septal defect or ventricular septal defect correction surgery at Shanghai Children′s Medical Center affiliated to Shanghai Jiao Tong University School of Medicine from December 2023 to February 2024 were selected. They were of either sex, aged 6 months to 3 yr, with a body mass index of 13-19 kg/m 2, and classified as American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ. Patients who adhered to the prescribed preoperative clear fluid fasting regimen, with a fasting duration of 6 h or longer before surgery, were included in the long fasting (LF) group, while those who were prescribed multi-dimensional nutritional solution until 2 h before surgery with a solid fasting duration≥6 h were considered for inclusion in the short fasting (SF) group. The diastolic blood pressure (DBP) was recorded immediately before and after liver compression test at pre-induction of anesthesia and immediately before and after liver compression test at post-induction of anesthesia, and the changes in DBP before and after the liver compression test (ΔDBP) were calculated. Positive fluid responsiveness was defined as an increase in ΔDBP ≥ 6.25%. The positive rate of fluid responsiveness before and after anesthesia induction was calculated. Results:Sixty-four patients were finally included, and both LF and SF groups included 32 cases. Before the induction of anesthesia, the positive rate of fluid responsiveness induced by liver compression was 28.1% in LF group and 18.8% in SF group, and the difference was not statistically significant ( P>0.05). However, after the induction of anesthesia, the positive rate of fluid responsiveness induced by liver compression was 56.3% in LF group and 28.0% in SF group, with a statistically significant difference observed ( P<0.05). Compared with the baseline before anesthesia induction, the positive rate of fluid responsiveness was significantly increased in LF group( P<0.05), and no significant change was found in the positive rate of fluid responsiveness in SF group ( P>0.05). Conclusions:The prolonged clear fluid fasting may lead to an increase in the positive rate of fluid responsiveness following anesthesia induction in pediatric patients with congenital heart disease, presenting as a state of hypovolemia.

AIM To investigate the clinical effects of Lingxian Tongluo Capsules combined with Wentong Acupuncture Method on patients with lumbar disc herniation.METHODS One hundred and four patients were randomly assigned into control group(52 cases)for 30-day intervention of both Wentong Acupuncture Method and conventional treatment,and observation group(52 cases)for 30-day intervention of Lingxian Tongluo Capsules,Wentong Acupuncture Method and conventional treatment.The changes in clinical effects,TCM syndrome scores,lumbar function indices(ODI index score,JOA score),VAS score,inflammatory factors(TNF-α,IL-1β,IL-6),hemorheological indices(plasma viscosity,whole blood high-shear viscosity,whole blood low-shear viscosity)and incidence of adverse reactions were detected.RESULTS The observation group demonstrated higher total effective rate than the control group(P＜0.05).After the treatment,the two groups displayed decreased TCM syndrome scores,ODI index score,VAS score,inflammatory factors and hemorheological indices(P＜0.05),and increased JOA score(P＜0.05),especially for the observation group(P＜0.05).No significant difference in incidence of adverse reactions was found between the two groups(P＞0.05).CONCLUSION For the patients with lumbar disc herniation,Lingxian Tongluo Capsules combined with Wentong Acupuncture Method can safely and effectively relieve clinical symptoms,promote lumbar function recovery,reduce pain degree,alleviate inflammatory responses,and improve hemorheology.

Objective:To summarize the clinical phenotypes and genetic variations of children with epilepsy related to CLCN4 gene mutations. Methods:A retrospective analysis was conducted on 9 children with epilepsy who were diagnosed with CLCN4 gene mutations through whole-exome sequencing of family members. These children were treated at the Department of Pediatrics, Peking University First Hospital from December 2016 to March 2024. Their clinical manifestations, electroencephalogram, cranial imaging characteristics, and treatment follow-up were reviewed. Results:Among the 9 children, 6 were male and 3 were female. All cases involved de novo mutations. Three cases carried the c.823G>A/p.V275M variant, 2 cases carried the c.2152C>T/ p.R718W variant, 1 case carried the c.1630G>A/pG544R variant, and 1 case carried the c.2167C>T/ p.R723W variant. Two cases carried the unreported new variant c.848G>T/p.S283I and c.818G>A/ p.G273E. The onset age of epilepsy ranged from 55 days to 10 years, with a median onset age of 14 months. Seven out of 9 children had epilepsy onset before the age of 2 years. The types of seizures varied: 8 had focal seizures, 1 had generalized tonic-clonic seizures, 2 had myoclonic seizures, 1 had epileptic spasms, and 1 had atypical absence seizures. Three children experienced multiple types of seizures. All 9 children exhibited developmental delays to varying degrees: 8 had global developmental delay and 1 had cognitive developmental delay. Developmental delays were observed in 7 children before the onset of epilepsy. Clinically, 1 child was diagnosed with infantile epileptic spasms syndrome, 7 with unclassified developmental and epileptic encephalopathy, and 1 with focal epilepsy with developmental delay. At the last follow-up, the age of the children ranged from 2 years and 5 months to 13 years and 9 months. Seizures had been controlled in 3 children for a duration of 4 to 12 months. Conclusions:De novo variants are common in CLCN4 variants. Most seizures onset in infancy, seizure types are various, and focal seizures are common. Most of them have developmental delay and drug-resistant epilepsy, and some of them have developmental delay before seizure onset, which is consistent with the characteristics of developmental and epileptic encephalopathy.