Objective: In in vitro systems for differentiating and expanding natural killer (NK) cells, feeder cells provide essential cell-cell contact and paracrine signals that drive precursor proliferation and terminal maturation. However, existing xenogeneic feeder cells or tumor-derived genetically modified feeder cells pose risks of residual immunogenicity and malignant transformation, limiting clinical use. This study aims to develop a humanized mesenchymal-like stromal cell (hematopoietic organoid-derived human mesenchymal stromal cells, HO-hMSCs) derived from iPSC-based hematopoietic organoids, and elucidate its mechanisms of NK-supportive activity to enable a safe, efficient platform for clinical-grade NK cell production. Methods: Human induced pluripotent stem cells (iPSCs) were differentiated into hematopoietic organoids, from which HO-hMSCs were isolated. Flow-cytometric phenotyping and bulk RNA-sequencing were performed to compare HO-hMSCs with umbilical cord-derived MSCs (UC-hMSCs). The effect of HO-hMSCs on NK cell differentiation efficiency (CD3 CD56 ) and effector maturation (CD16 expression) were assessed by co-culture experiments, using UC-hMSCs as control. Results: 1) Hematopoietic organoid induction and NK differentiation: iPSCs were induced to form hematopoietic organoids using cytokine cocktails, which further differentiated into high-purity CD45 CD56 NK cells [(82.8%±12.07)% efficiency on day 21]. 2) HO-hMSC characteristics: HO-hMSCs exhibited upregulated expression of Notch pathway ligands (DLL4, JAG1, 4.06-8.04-fold), homeobox genes (HOXA3, HOXA5, log FC=1.28 and 1.44), and key regulators of NK development (GATA3, BCL11A) and cytokine receptors (IL7R, IL27RA, 6.76 to 13.34-fold increase). 3) Functional validation: Compared to UC-hMSCs, HO-hMSCs co-culture significantly enhanced NK cell proportion by 30.5% (P<0.05) and increased CD16 positivity (+20.5%). Conclusion: This study for the first time reveals that human hematopoietic organoid-derived HO-hMSCs possess potent hematopoietic niche-supportive activity. It provides a humanized, feeder-free platform for robust clinical-grade NK cell production and expands the translational utility of organoid technologies in cell therapy.

Acute liver injury (ALI) serves as a critical precursor and major etiological factor in the progression and ultimate manifestation of various hepatic disorders. The prevention and treatment of ALI is still a serious global challenge. Given the limited therapeutic options for ALI, exploring novel targeted therapeutic agents becomes imperative. The potential therapeutic efficacy of inhibiting RIPK2 is highlighted, as it may provide significant benefits by attenuating the MAPK pathway and NF-κB signaling. Herein, we propose a CMD-OPT model, a two-stage molecular optimization tool for the rapid discovery of RIPK2 inhibitors with optimal properties. Compound RP20, which targets the ATP binding site, demonstrated excellent kinase specificity, ideal oral pharmacokinetics, and superior therapeutic effects in a model of APAP-induced ALI, positioning RP20 as a promising preclinical candidate. This marks the first application of RIPK2 inhibitors in ALI treatment, opening a novel therapeutic pathway for clinical applications. These results highlight the efficacy of the CMD-OPT model in producing lead compounds from known active molecules, showcasing its significant potential in drug discovery.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Background and aim:Hepatic ischemia-reperfusion injury(IRI)is a significant challenge in liver trans-plantation,trauma,hypovolemic shock,and hepatectomy,with limited effective interventions available.This study aimed to investigate the role of leukocyte cell-derived chemotaxin 2(LECT2)in hepatic IRI and assess the therapeutic potential of Lect2-short hairpin RNA(shRNA)delivered through adeno-associated virus(AAV)vectors. Materials and methods:This study analyzed human liver and serum samples from five patients under-going the Pringle maneuver.Lect2-knockout and C57BL/6J mice were used.Hepatic IRI was induced by clamping the hepatic pedicle.Treatments included recombinant human LECT2(rLECT2)and AAV-Lect2-shRNA.LECT2 expression levels and serum biomarkers including alanine aminotransferase(ALT),aspartate aminotransferase(AST),creatinine,and blood urea nitrogen(BUN)were measured.Histological analysis of liver necrosis and quantitative reverse-transcription polymerase chain reaction were performed. Results:Serum and liver LECT2 levels were elevated during hepatic IRI.Serum LECT2 protein and mRNA levels increased post reperfusion.Lect2-knockout mice had reduced weight loss;hepatic necrosis;and serum ALT,AST,creatinine,and BUN levels.rLECT2 treatment exacerbated weight loss,hepatic necrosis,and serum biomarkers(ALT,AST,creatinine,and BUN).AAV-Lect2-shRNA treatment significantly reduced weight loss,hepatic necrosis,and serum biomarkers(ALT,AST,creatinine,and BUN),indicating thera-peutic potential. Conclusions:Elevated LECT2 levels during hepatic IRI increased liver damage.Genetic knockout or shRNA-mediated knockdown of Lect2 reduced liver damage,indicating its therapeutic potential.AAV-mediated Lect2-shRNA delivery mitigated hepatic IRI,offering a potential new treatment strategy to enhance clinical outcomes for patients undergoing liver-related surgeries or trauma.

Objective To investigate the causes of a cluster of suspected neonatal carbapenem-resistant Klebsiella pneumoniae(CRKP)bloodstream infection(BSI)in the neonatal department of a hospital,and provide references for the effective control of the occurrence of healthcare-associated infection(HAI).Methods Epidemiological in-vestigation on 3 neonates with CRKP BSI in the neonatal department from January 31 to February 6,2023 was per-formed.Specimens from environmental object surfaces were taken for environmental hygiene monitoring,and effec-tive control measures were taken according to the risk factors.Results From January 31 to February 6,2023,a to-tal of 60 neonates were admitted in the neonatal department,including 16 with peripherally inserted central venous catheter(PICC).Three neonates had CRKP BSI,with a incidence of 5.00％.There were 33 hospitalized neonates on the day(February 7)when the cluster of HAI was reported,with a prevalence rate of 9.09％(3/33).CRKP BSI rate in the neonatal department of this hospital from January 31 to February 6,2023 was higher than that in 2022(P＜0.001).The incubators of the 3 neonates with CRKP BSI were in the same ward and adjacent to each other.The first neonate with CRKP BSI(who developed BSI on January 31)underwent PICC maintenance on Feb-ruary 4,and the other 2 neonates with PICC maintenance immediately following the first one also developed CRKP BSI.CRKP were isolated from blood culture of all 3 neonates,and antimicrobial susceptibility testing results were consistent.Conclusion The occurrence of the cluster event of neonatal CRKP BSI may be related to the failure of strict implementation of aseptic procedures during PICC maintenance and cross contamination among items.

Pancreatic cancer (PC) is a highly fatal disease which originated from pancreatic epithelial and acinar cells, and the survival rate of pancreatic cancer patients is only about 12%. Approximately 95% of pancreatic cancer presents as ductal adenocarcinoma (PDAC). Pancreatic cancer is characterized by high aggressiveness, rapid progression and progression, and high resistance to treatment. Common somatic mutated genes in the early stage of pancreatic cancer include KRAS, CDKN2A, TP53, and SMAD4. Most pancreatic cancer patients are affected by environmental risk factors such as age, sex and diet. Malignant pancreatic cancer is associated with non-invasive, preneoplastic lesions that are thoughted to be precursors, such as pancreatic intraepithelial neoplasia (PanIN), intraductal papillary mucinous neoplasm (IPMN) and mucinous cystadenoma (MCN). In recent years, people have gradually improved the therapy and diagnosis of pancreatic cancer, and the contribution of imaging technology, which enhancing the usage of minimally invasive pancreatectomy that typically includes pancreaticoduodenectomy and distal pancreatectomy. However, combined administration of the chemotherapeutic gemcitabine and erlotinib is still considered a potential first-line treatment for advanced pancreatic cancer, but the development of chemoresistance often leads to poor therapeutic outcomes. Based on the current research progress for pancreatic cancer, its treatment currently remains one of the most important challenges in the medical field. Although some new treatment options have been provided, there were minor clinical success achieved and therefore new safe and effective therapies of pancreatic cancer are still an urgent need for patients. Among these new therapies for pancreatic cancer, short peptide-based treatment protocols have attracted great attention. Peptide is a compound formed by linking α-amino acids together in peptide chains. It is also an intermediate product of proteolysis. The short peptide-based therapy has many advantages such as precise targeting, easy preparation and low toxicity. Short peptides usually act as tumor suppressors by targeting and recognizing tumor-specific expressed proteins. Currently, there is an increased interest in peptides in pharmaceutical and development research, and approximate 140 peptide therapeutics are currently being evaluated in clinical trials. These peptides provide excellent prospects for targeted drug delivery because of their high selectivity, specificity and simplicity of modification. Peptides have high bioactivity and excellent biodegradability. Clinically, short peptides are increasingly used as combination drugs with chemotherapy for tumor treatment. Peptides can induce cancer cell death by numerous mechanisms and peptides have emerged as a promising drug for the treatment of pancreatic cancer. Here we mainly review the roles of peptides on Wnt/β-catenin, NF-κB, autophagy, and the use of peptides as tracer in pancreatic cancer. We also analyzed the benefits and disadvantages existing in the development process of short peptides, which provide the feasibility of targeted short peptides to become new therapeutic approaches for cancer therapy.

Objective To compare the effects of 20 mg qd and 10 mg bidadministration of iprrazole enteric-coated tablets on the control of gastric acid in healthy subjects.Methods A randomized,single-center,parallel controlled trial was designed to include 8 healthy subjects.Randomly divided into 2 groups,20 mg qd administration group:20 mg enteric-coated tablets of iprrazole in the morning;10 mg bid administration group:10 mg enteric-coated tablets of iprrazole in the morning and 10 mg in the evening.The pH values in the stomach of the subjects before and 24 h after administration were monitored by pH meter.The plasma concentration of iprazole after administration was determined by HPLC-MS/MS.The main pharmacokinetic parameters were calculated by Phoenix WinNonlin(V8.0)software.Results The PK parameters of iprrazole enteric-coated tablets and reference preparations in fasting group were as follows:The Cmax of 20 mg qd group and 10 mg bid group were(595.75±131.15)and(283.50±96.98)ng·mL-1;AUC0-t were(5 531.94±784.35)and(4 686.67±898.23)h·ng·mL-1;AUC0-∞ were(6 003.19±538.59)and(7 361.48±1 816.77)h·ng·mL-1,respectively.The mean time percentage of gastric pH＞3 after 20 mg qd and 10 mg bid were 82.64％and 61.92％,and the median gastric pH within 24 h were 6.25±1.49 and 3.53±2.05,respectively.The mean gastric pH values within 24 h were 5.71±1.36 and 4.23±1.45,respectively.The correlation analysis of pharmacokinetic/pharmacodynamics showed that there was no significant correlation between the peak concentration of drug in plasma and the inhibitory effect of acid.Conclusion Compared with the 20 mg qd group and the 10 mg bid group,the acid inhibition effect is better,the administration times are less,and the safety of the two administration regimes is good.

Objective Vasculogenic mimicry(VM)is a novel vasculogenic process integral to glioma stem cells(GSCs)in glioblastoma(GBM).However,the relationship between VM and ataxia-telangiectasia mutated(ATM)serine/threonine kinase activation,which confers chemoradiotherapy resistance,remains unclear. Methods We investigated VM formation and phosphorylated ATM(pATM)levels by CD31/GFAP-periodic acid-Schiff dual staining and immunohistochemical staining in 145 GBM specimens.Glioma stem-like cells(GSLCs)derived from the formatted spheres of U87 and U251 cell lines and their pATM level and VM formation ability were examined using western blot and three-dimensional culture.For the examination of the function of pATM in VM formation by GSLCs,ATM knockdown by shRNAs and deactivated via ATM phosphorylation inhibitor KU55933 were studied. Results VM and high pATM expression occurred in 38.5%and 41.8%of tumors,respectively,and were significantly associated with reduced progression-free and overall survival.Patients with VM-positive GBMs exhibited higher pATM levels(rs=0.425,P=0.01).The multivariate analysis established VM as an independent negative prognostic factor(P=0.002).Furthermore,GSLCs expressed high levels of pATM and formed vascular-like networks in vitro.ATM inactivation or knockdown hindered VM-like network formation concomitant with the downregulation of pVEGFR-2,VE-cadherin,and laminin B2. Conclusion VM may predict a poor GBM prognosis and is associated with pATM expression.We propose that pATM promotes VM through extracellular matrix modulation and VE-Cadherin/pVEGFR-2 activation,thereby highlighting ATM activation as a potential target for enhancing anti-angiogenesis therapies for GBM.

Objective Utilizing a specially engineered miR-144-GFP-H1 human embryonic stem cell(hESC)reporter line,this study leverages GFP fluorescence as an indicator of miR-144 expression to gauge the progression of erythropoiesis.The investigation is aimed at elucidating the potential roles of lncRNAs within the erythropoietic framework and conducting an initial assessment of their functional impact.Methods The miR-144/451-GFP-H1 cell line(hereafter referred to as 144-H1)was utilized for in vitro erythrocyte induction culture.The subpopulations of cells entering the erythropoiesis stage were characterized by the surface molecules CD71 and GPA.The GFP reporter gene of miR-144 served as a critical determi-nant to distinguish between GFP-positive cells(with a high propensity for erythropoiesis)and GFP-negative cells(with a low propensity for erythropoiesis).Transcriptome sequencing was performed on both groups to identify differentially ex-pressed long non-coding RNAs(lncRNAs).LncRNA entries with potential for validation were selected for preliminary func-tional verification.The CRISPR/Cas9 gene editing technique was employed to design functional interference strategies for the targeted lncRNAs,obtaining 144-H1 cell lines with knocked-out function of the specific lncRNAs.These knockout cell lines,along with non-knockout 144-H1 cell lines,were used for parallel erythrocyte induction culture to identify differential nodes.This approach preliminarily verified their impact on erythropoiesis in an in vitro development model.Results 1)The constructed 144-H1 cell line was capable of expressing GFP fluorescence upon entering the stage of in vitro erythrocyte in-duction,indicating the activation of miR-144/451.2)Within the CD71,GPA double-positive group,significant differences in lncRNA expression were observed between the GFP-positive and GFP-negative subpopulations.3)Gene editing strategies involving the deletion of sequence segments capable of effectively interfering with the function of multiple lncRNA entries were designed and verified for successful editing.In the knockout cell lines,parts of the lncRNA sequences were directly de-leted.4)In parallel validation experiments of erythrocyte induction culture,cell lines with LINC01569 knocked out exhibited significant differences in flow cytometric subpopulations and cell proliferation capabilities compared to the non-knockout cell lines:①The knockout cell lines showed sustained high expression of GFP fluorescence.②The proportion of the CD71-GPA double-positive group in the knockout cell lines continuously decreased during erythrocyte maturation.③No significant ex-pression of hemoglobin was observed in the knockout cell lines,lacking the characteristic red color.④The cell proliferation capability of the knockout cell lines was significantly lower than that of the non-knockout cell lines(P＜0.05).Conclusion The successful employment of the 144-H1 cell line facilitated an exploration into the potential functions of lncRNAs in e-rythropoiesis.This enables the design of more refined in vitro developmental experiments to enhance the precision in captu-ring lncRNA functions.Among the differentially expressed lncRNA entries,LINC01569 was preliminarily validated to play a regulatory role in erythropoiesis.The functional absence of LINC01569 severely impacts the normal differentiation and prolif-eration of erythrocytes.The specific regulatory mechanism of LINC01569 in erythropoiesis warrants further investigation and research.