Antibodies play a critical role in adaptive immune responses and serve as key components in disease diagnosis and treatment. These molecules exhibit dynamic post-translational modifications (PTMs), such as glycosylation and phosphorylation, which regulate their effector functions. To date, nearly all of our knowledge about antibody repertoires has come from B cell receptor (BCR) sequencing (BCR-seq), which facilitates the profiling of clonal composition and the tracing of maturation trajectories within B-cell repertoires. However, circulating antibodies found in bodily fluids—such as serum, saliva, milk, mucosal secretions, and cerebrospinal fluid—exhibit diversities and specificities beyond what BCR-seq alone can predict. Therefore, identifying and quantifying antibody clonotypes at the protein level could enhance diagnosis, prognosis, and treatment strategies in personalized medicine. The critical gap between genotype and phenotype necessitates complementary methodologies that enable the direct characterization of antibody proteins in their native functional states. Mass spectrometry (MS)-based antibody repertoire sequencing (Ab-seq) is currently the only feasible approach for this task and primarily includes database-dependent methods—such as bottom-up, middle-down, and top-down approaches—as well as database-independent de novo sequencing technology. These strategies enable multi-level, high-precision characterization ranging from peptides and domains to intact antibody molecules. Unlike the shotgun strategy commonly used in routine proteomics, obtaining full sequences of all antibodies presents unique challenges. It requires specialized methodological adaptations to address issues related to dynamic range, sequence variation, and sample complexity. This review introduces the technical principles, methodological workflows, and recent applications of various mass spectrometry-based antibody repertoire sequencing (Ab-seq) strategies, with a focus on approaches designed to improve sequence coverage and identification accuracy. These include multi-enzyme digestion, hybrid fragmentation methods, and artificial intelligence-assisted de novo sequencing. By systematically comparing database-dependent techniques—such as bottom-up, middle-down, and top-down approaches—with database-independent de novo sequencing, this review outlines their respective advantages and limitations in terms of sample throughput, sequence coverage, post-translational modification characterization, and data analysis complexity. In addition, this review discusses emerging technological trends, including the integration of ion mobility separation, native mass spectrometry, and artificial intelligence-driven data interpretation, which are expected to enhance the depth and accuracy of antibody characterization. Although current methods continue to face challenges related to sample complexity, dynamic range, and unambiguous sequence variant assignment, we emphasize the importance of integrating BCR-seq and Ab-seq data to construct gene-protein association maps. These maps help validate sequence accuracy and facilitate epitope discovery. This dual-platform strategy helps bridge the gap between genotype and phenotype, thereby enhancing both the resolution and scope of antibody repertoire studies. Such an integrative approach also offers a valuable tool for therapeutic antibody development, structure-function analysis, and precise evaluation of vaccine efficacy.

Aim To explore the mechanism by which the compound Chaijin Jieyu formula(CCJJY)regulates the TLR4/NLRP3 signaling pathway to inhibit central oxidative stress and improve hippocampal synaptic plasticity damage in depression.Methods SD rats were randomly divided into the control group,chronic unpredictable mild stress group,sleep deprivation group,chronic unpredictable mild stress combined with sleep deprivation group,positive drug group(venlafax-ine+melatonin),low-dose group of CCJJY,medium dose group of CCJJY,and high-dose group of CCJJY,with nine rats in each group.Except for the control group,a rat model of depression complicated with in-somnia was established using chronic unpredictable mild stress combined with sleep deprivation.Depres-sion-like and sleep behaviors in rats were evaluated through weight,food intake,water maze,and pento-barbital sodium tests.ELisa was used to detect ROS,AANAT,and HPLC-EC was used to detect 5-HT con-tent,while Western blot/RT-PCR was used to detect the expression of IL-1β,TLR4,NLRP3,PSD-95,and SYN related proteins and mRNA.HE and Golgic stai-ning were used to observe the pathological changes in the third ventricle,hippocampus,and neuronal synap-ses.Results Compared with the control group,the depression-like behaviors of the model group rats were significant.The expression of IL-1β,TLR4,and NL-RP3 in the hippocampus increased,while the expres-sion of PSD-95 and SYN decreased.Activation of NL-RP3 inflammasomes led to "sleeve like" pathological changes in the third ventricle,with hippocampal neu-rons undergoing apoptosis and significant damage to neuronal synaptic plasticity.Compared with the model group,after intervention with CCJJY,the expression of ROS,IL-1β,TLR4,and NLRP3 decreased,while the expression of AANAT,5-HT,PSD-95,and SYN in-creased.Pathological damage to the third ventricle and hippocampal neurons was repaired.Conclusion The CCJJY improves hippocampal synaptic plasticity dam-age in depression by regulating the TLR4/NLRP3 sig-naling pathway to inhibit central oxidative stress.

AIM To investigate the stability of salvianolic acid B.METHODS HPLC was adopted in the content determination of salvianolic acid B,after which the chemical stability in different pH of buffer solutions,oxidation stability in different concentrations of H2O2,and biological stability in artificial gastric fluid,artificial intestinal fluid and biological matrices were analyzed,and its degradation kinetics was fitted.RESULTS Salvianolic acid B was stable in acidic and weakly acidic buffer solutions and artificial gastric fluid,which demonstrated poor stability in neutral and alkaline buffer solutions,artificial intestinal fluid,H2O2 and biological matrices.The degradation process of this constituent accorded with the first-order kinetic model in ileum homogenate,and the second-order kinetic model in pH 7.4 buffer solution,artificial intestinal fluid,H2O2 and stomach,duodenum,jejunum,colon homogenates.CONCLUSION Biological matrices,oxidants and alkaline environment can affect the stability of salvianolic acid B.This experimental exhibits important significance for the development and application of salvianolic acid B-related products.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Aim To explore the mechanism by which the compound Chaijin Jieyu formula(CCJJY)regulates the TLR4/NLRP3 signaling pathway to inhibit central oxidative stress and improve hippocampal synaptic plasticity damage in depression.Methods SD rats were randomly divided into the control group,chronic unpredictable mild stress group,sleep deprivation group,chronic unpredictable mild stress combined with sleep deprivation group,positive drug group(venlafax-ine+melatonin),low-dose group of CCJJY,medium dose group of CCJJY,and high-dose group of CCJJY,with nine rats in each group.Except for the control group,a rat model of depression complicated with in-somnia was established using chronic unpredictable mild stress combined with sleep deprivation.Depres-sion-like and sleep behaviors in rats were evaluated through weight,food intake,water maze,and pento-barbital sodium tests.ELisa was used to detect ROS,AANAT,and HPLC-EC was used to detect 5-HT con-tent,while Western blot/RT-PCR was used to detect the expression of IL-1β,TLR4,NLRP3,PSD-95,and SYN related proteins and mRNA.HE and Golgic stai-ning were used to observe the pathological changes in the third ventricle,hippocampus,and neuronal synap-ses.Results Compared with the control group,the depression-like behaviors of the model group rats were significant.The expression of IL-1β,TLR4,and NL-RP3 in the hippocampus increased,while the expres-sion of PSD-95 and SYN decreased.Activation of NL-RP3 inflammasomes led to "sleeve like" pathological changes in the third ventricle,with hippocampal neu-rons undergoing apoptosis and significant damage to neuronal synaptic plasticity.Compared with the model group,after intervention with CCJJY,the expression of ROS,IL-1β,TLR4,and NLRP3 decreased,while the expression of AANAT,5-HT,PSD-95,and SYN in-creased.Pathological damage to the third ventricle and hippocampal neurons was repaired.Conclusion The CCJJY improves hippocampal synaptic plasticity dam-age in depression by regulating the TLR4/NLRP3 sig-naling pathway to inhibit central oxidative stress.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To investigate the effect of sal-like gene 2(Sall2)gene overexpression on the progression of disease in human superoxide dismutase 1(hSOD1)-G93A mutant amyotrophic lateral sclerosis(ALS)transgenic mice,with the aim of identifying potential therapeutic targets for ALS gene therapy.Methods Differential Sall2 gene were screened through bioinformatics analysis.Forty-eight ALS transgenic mice were selected for this study.AAV-PHP.eB-Sall2 adeno-associated virus with a neuron-specific promoter,human synapsin I(hSyn),was constructed and administered via tail vein injection to six-week-old mice.In parallel,the same litter of ALS mice received an injection of AAV-PHP.eB-GFP.The staining of Sall2 and neuron-specific nuclear protein(NeuN)/GFAP in the spinal cord and cerebral cortex of mice were detected through immunofluorescent double-label staining technology.The survival period,weight changes,exercise ability,and electromyographic changes of the gastrocnemius muscle were detected.The morphological changes in the spinal cord anterior horn neurons were detected through Nissl staining.The effect of Sall2 gene overexpression on the expression of the cell cycle protein E1(cyclin E1)was investigated through Western blotting.Results Bioinformatics analysis showed out that Sall2 was differentially expressed in ALS mice.Compared with ALS mice in the control group,the Sall2 protein expression of ALS mice in the overexpressing Sall2 gene group increased in both the spinal cord and cerebral cortex,and the Sall2 integral absorbance values of Sall2+/NeuN+double-positive cells were higher.The survival time of ALS mice in the Sall2 gene overexpressing group was prolonged,the rate of weight loss was slowed down,the performance in the rotarod and inverted grid tests was improved with longer times,and the positive sharp waves and fibrillation potentials in the gastrocnemius electromyography were reduced.The number of Nissl bodies labeled neurons increased in the spinal cord anterior horn of the Sall2 gene overexpressing mice,and the condition of neuronal damage was improved.Overexpression of the Sall2 gene also reduced the expression of cyclin E1 in both the spinal cord and cerebral cortex of ALS transgenic mice.Conclusion Overexpression of the Sall2 gene can delay disease progression and improve motor performance in ALS transgenic mice,affecting the expression of cyclin E1,thus exerting a therapeutic effect on these mice.

Objective To explore the role of SLIT-ROBO Rho GTPase-activating protein 2(srGAP2)in spinal motor neuron degeneration in amyotrophic lateral sclerosis(ALS).Methods Applied bioinformatics analysis to investigate the expression changes of srGAP2 in the spinal cord of human superoxide dismutase 1(hSOD1)mutant ALS transgenic mice.hSOD1 G93A mutant ALS transgenic mice were selected for animal experimental validation,with littermate wild type(WT)mice serving as the control group.A total of 36 pairs were divided into four groups,namely the pre-onset stage,early-onset stage,mid-onset stage,and late-onset stage.The expression changes and cellular localization of srGAP2 in the spinal cord of ALS mice were detected by Real-time PCR,Western blotting and immunofluorescent double-label staining.The hSOD1G93A mutant NSC34 motor neuron-like cell model was established,and in vitro experiments were carried out to detect the changes in srGAP2 expression,and the effects of srGAP2 over-expression on the viability of hSOD1G93A mutant NSC34 cells and the growth of cell protrusions.Results Bioinformatics analysis revealed abnormally low expression of srGAP2 in the spinal cord of hSOD1 mutant ALS mice.Animal experiments verified that compared with the WT mice,the expression of srGAP2 was reduced at both mRNA level and protein level in the spinal cord of hSOD1G93A mutant ALS transgenic mice at early-onset,mid-onset and late-onset stages.Compared with the WT mice,srGAP2 integral absorbance(IA)values in srGAP2+/NeuN+double-positive cells in the anterior horn of the spinal cord of hSOD1G93A mutant ALS transgenic mice were lower,srGAP2 IA values in srGAP2+/GFAP+double-positive cells were higher;Compared with the hSOD1WT NSC34 cells,the expression of srGAP2 was reduced at both mRNA level and protein level in hSOD1G93A mutant NSC34 cells.Over-expression of srGAP2 elevated the viability of hSOD1G93A mutant NSC34 cells,and up-regulated the expression level of synapse-related protein β Ⅲ-tubulin and growth associated protein 43(GAP43).Conclusion Low expression of srGAP2 is closely associated with the progression of ALS,while over-expression of srGAP2 can promote outgrowth of cell protrusions and exert a protective effect on spinal motor neurons in ALS.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.