ObjectiveThe malaria parasites remodel the host erythrocyte structure by exporting parasite proteins that interact with the membrane skeleton proteins of red blood cells (RBCs), facilitating their intracellular survival and pathogenicity. Skeleton-binding protein 1 (SBP1) is a conserved exported protein across Plasmodium species. In Plasmodium falciparum, SBP1 has been reported to interact with erythrocyte membrane skeleton proteins 4.1R and spectrin, while its contribution to erythrocyte remodeling and parasite virulence in Plasmodium berghei (Pb) remains unclear. This study aims to determine whether PbSBP1 associates with the host cytoskeletal protein 4.1R and to investigate its role in the remodeling of host RBCs and the pathogenicity of Plasmodium berghei. MethodsIn Plasmodium berghei, the relationship between PbSBP1 and the erythrocyte cytoskeletal protein 4.1R was examined using co-immunoprecipitation. A Pbsbp1 gene knockout mutant of Plasmodium berghei (Pbsbp1∆) was generated based on the principle of double crossover homologous recombination. The deformability of erythrocytes infected with Pbsbp1∆ parasites was assessed using microfluidic methods. Microchannels with an array of cylindrical pillars were used to detect modifications in infected RBC deformability. The infected RBCs were squashed between the rows and recovered between the columns and the transit velocity (μm/s) of infected RBCs travelling through the microchannel was recorded. The component of the erythrocyte membrane skeleton junctional complex, tropomodulin (TMOD), was fluorescently labeled, and the cytoskeletal network of infected erythrocytes was imaged using super-resolution stochastic optical reconstruction microscopy (STORM) to analyze ultrastructural changes in the cytoskeleton of wild-type (WT) and Pbsbp1∆-infected erythrocytes. Actin-based junctional complexes were displayed as individual clusters by the labeled TMOD in the STORM images, and the cluster densities and distances between adjacent clusters of infected RBCs were calculated. Additionally, rodent malaria models (BALB/c mice) and experimental cerebral malaria models (C57BL/6 mice) were employed to monitor the growth of Pbsbp1∆ and WT parasites during the intraerythrocytic stage and their capacity to induce cerebral malaria in mice. ResultsPbSBP1 may participate in the remodeling of infected erythrocytes through direct or indirect interaction with the erythrocyte cytoskeletal protein 4.1R. Microfluidic assays revealed that the deformability of erythrocytes infected with Pbsbp1∆ parasites was significantly enhanced compared to those infected with WT parasites. STORM imaging further demonstrated that the ultrastructure of the erythrocyte cytoskeleton in Pbsbp1∆-infected cells was altered relative to that in WT-infected erythrocytes. The distances between nearest neighbors of clusters had a tendency to increase while the cluster densities were decreased in Pbsbp1∆-infected RBCs compared to WT-infected RBCs. Subsequent phenotypic analysis indicated that the growth rate of Pbsbp1∆ parasites during the intraerythrocytic stage was significantly slower than that of WT parasites, and their ability to induce cerebral malaria in mice was also attenuated. These findings suggest that PbSBP1 is involved in the remodeling of the erythrocyte membrane skeleton, likely through its direct or indirect interaction with protein 4.1R, thereby regulating the deformability of infected erythrocytes and influencing the pathogenicity of the blood-stage parasites. ConclusionThis study establishes a role for PbSBP1 in host erythrocyte remodeling and parasite virulence, providing new research strategies for the prevention and treatment of malaria.

Objective To explore the construction of α-1,3-galactosyltransferase (GGTA1) gene-knockout (GTKO) Diannan miniature pigs and the kidney xenotransplantation from pigs to rhesus macaques, and to assess the effectiveness of GTKO pigs. Methods The GTKO Diannan miniature pigs were constructed using the CRISPR/Cas9 gene-editing system and somatic cell cloning technology. The phenotype of GTKO pigs was verified through polymerase chain reaction, Sanger sequencing and immunofluorescence staining. Flow cytometry was used to detect antigen-antibody (IgM) binding and complement-dependent cytotoxicity. Kidney xenotransplantation was performed from GTKO pigs to rhesus macaques. The humoral immunity, cellular immunity, coagulation and physiological indicators of the recipient monkeys were monitored. The function and pathological changes of the transplanted kidneys were analyzed using ultrasonography, hematoxylin-eosin staining, immunohistochemical staining and immunofluorescence staining. Results Single-guide RNA (sgRNA) targeting exon 4 of the GGTA1 gene in Diannan miniature pigs was designed. The pGL3-GGTA1-sgRNA1-GFP vector was transfected into fetal fibroblasts of Diannan miniature pigs. After puromycin selection, two cell clones, C59# and C89#, were identified as GGTA1 gene-knockout clones. These clones were expanded to form cell lines, which were used as donor cells for somatic cell nuclear transfer. The reconstructed embryos were transferred into the oviducts of trihybrid surrogate sows, resulting in 13 fetal pigs. Among them, fetuses F04 and F11 exhibited biallelic mutations in the GGTA1 gene, and F04 had a normal karyotype. Using this GTKO fetal pig for recloning and transferring the reconstructed embryos into the oviducts of trihybrid surrogate sows, seven surviving piglets were obtained, all of which did not express α-Gal epitope. The binding of IgM from the serum of rhesus monkey 20# to GTKO pig PBMC was reduced, and the survival rate of GTKO pig PBMC in the complement-dependent cytotoxicity assay was higher than that of wild-type pig. GTKO pig kidneys were harvested and perfused until completely white. After the left kidney of the recipient monkey was removed, the pig kidney was heterotopically transplanted. Following vascular anastomosis and blood flow restoration, the pig kidney rapidly turned pink without hyperacute rejection (HAR). Urine appeared in the ureter 6 minutes later, indicating successful kidney transplantation. The right kidney of the recipient was then removed. Seven days after transplantation, the transplanted kidney had good blood flow, the recipient monkey's serum creatinine level was stable, and serum potassium and cystatin C levels were effectively controlled, although they increased 10 days after transplantation. Seven days after transplantation, the levels of white blood cells, lymphocytes, monocytes and eosinophils in the recipient monkey increased, while platelet count and fibrinogen levels decreased. The activated partial thromboplastin time, thrombin time and prothrombin time remained relatively stable but later showed an upward trend. The recipient monkey survived for 10 days. At autopsy, the transplanted kidney was found to be congested, swollen and necrotic, with a small amount of IgG deposition in the renal tissue, and a large amount of IgM, complement C3c and C4d deposition, as well as CD68⁺ macrophage infiltration. Conclusions The kidneys of GTKO Diannan miniature pigs may maintain normal renal function for a certain period in rhesus macaques and effectively overcome HAR, confirming the effectiveness of GTKO pigs for xenotransplantation.

Objective To identify S-palmitoylation sites on angiotensin-converting enzyme 2(ACE2),the cellular receptor for severe acute respiratory syndrome corona virus(SARS-CoV)and SARS-CoV-2,and to investigate the functional relevance of these modifications in regulating ACE2 localization and activity.Methods An optimized multi-site mutagenesis strategy was performed by simultaneously substitution of all eight cysteine(Cys)residuesin ACE2 by serine to create a non-palmitoylatable mutant(8CS).Then individual cysteine residues were re-introduced one by one.Palmitoylation level of mutants was evaluated using a bioorthogonal click chemistry method to identify palmitoylation-competent residues.Immune-fluorescence staining and extra-cellular vesicle isolation assays were then used to evaluate the impact of specific palmitoylation sites on ACE2 sub-cellular localization.Results An efficient strategy for multi-site palmitoylation site mapping was optimized and successfully identified three critical palmitoylation sites on ACE2:Cys141,Cys344 and Cys498.Functional analyses showed that palmi-toylation of these sites significantly promotes the enrichment of ACE2 in extra-cellular vesicles.Conclusions S-palmitoylation at Cys141,Cys344 and Cys498 is essential for the trafficking of ACE2 to extra-cellular vesicles,which suggests a potential regulatory mechanism of its impact on viral receptor presentation and ACE2-associated signaling pathways.

6-Thioguanine(6-TG)is an antineoplastic agent used in treatment of acute leukemia.However,significant interindividual variability in dosing regimens and frequent clinical manifestations of hepatotoxicity and myelosuppression as adverse effects have affected its therapeutic efficacy.Consequently,the development of rapid analytical methods for 6-TG in clinical samples,enabling continuous therapeutic drug monitoring of plasma concentrations,holds substantial significance in optimizing dosage regimens,mitigating adverse reactions,and investigating drug metabolism mechanisms.In this study,multi-tipped gold nanostars(AuNSs)were prepared.With bis-(p-sulfonylphenyl)phenylphosphine molecule as the protecting agent and internal standard molecule,the AuNSs were assembled onto a highly sensitive surface-enhanced Raman(SERS)substrate for developing a ratio-based SERS quantitative analysis method for 6-TG in serum.The AuNSs containing multiple tips and gaps exhibited strong local surface plasmon resonance effect and SERS activity,ensuring the sensitivity of the analytical method.Furthermore,the introduction of internal standard molecules could improve the reproducibility,which guaranteed this method suitable for rapid analysis of drug molecules in complex samples.Quantitative analysis of 6-TG was achieved with linear detetion range of 1.0×10?4-1.0 mmol/L.In the spiked recovery experiments of serum,the RSD was less than 5.32%,and the recoveries were 94%-104%,which proved that this method could be used for rapid quantitative determination of 6-TG in serum.This method provided a powerful tool for studying drug pharmacokinetics,which could promote the optimization of the usage methods of anti-cancer drugs,and it was expected to further enhance the clinical efficacy and safety of 6-TG,enabling it to achieve the best therapeutic effect.

Due to the poor ionization efficiency and the weak mass spectrometry(MS)intensity of weakly polar substances,direct analysis using the traditional electrospray ionization mass spectrometry(ESI-MS)is a big challenge.In this study,a novel rapid on-site detection method of four prohibited sex hormones in cosmetics was proposed using online derivatization strategy coupled with a miniature mass spectrometer.The target substances in the samples were extracted by a custom-made polyaniline/multi-walled carbon nanotube solid-phase microextraction(SPME)probe.The stirring speed was 200 r/min,the extraction temperature was 40℃,and the extraction time was 2 min.A pulled dual-channel θ borosilicate glass capillary emitter was used as the nano-ESI ion source.The SPME probe was inserted into the channel containing methanol in theθborosilicate glass capillary.When the spray voltage was applied,the four sex hormones were desorbed and formed spray microdroplets,which then collided with the hydroxylamine microdroplets generated from the other channel.The microdroplets of reaction product entered into the miniature mass spectrometer for direct analysis.The limits of detection(LOD)and limits of quantification(LOQ)for the four sex hormones were 10-20 ng/mL and 20-50 ng/mL,respectively.The recoveries were from 84.6%to 107.8%with the relative standard deviations(RSD)from 4.1%to 11.6%.Compared to detection without derivatization,the MS signals of the four target substances were increased by 3 to 15 times.This method was simple,rapid,highly efficient and sensitive,and suitable for on-site rapid analysis of weakly polar sex hormones in cosmetics.

Objective To explore serum levels of serine/threonine protein kinase 4(MST4)and heat shock protein 70(HSP70)in children with idiopathic immune thrombocytopenia(ITP)and their clinical signifi-cance.Methods Totally 98 children with ITP admitted to Northwest Women and Children's Hospital from April 2019 to April 2023 were retrospectively selected as the ITP group,and 50 healthy children who under-went physical examination during the same period were selected as the control group.Enzyme linked immu-nosorbent assay was used to detect serum levels of MST4 and HSP70,and the serum MST4 and HSP70 levels in children with different ITP levels were compared.The correlation between the indicators were analyzed by Pearson correlation.Logistic regression model was used to screen the prognostic factors of ITP,and the as-sessment value of serum MST4 and HSP70 on ITP prognosis was analyzed by subject working characteristic curve.Results Serum MST4,HSP70,and CD8 in the ITP group were higher than those in the control group,while PLT,CD3+,CD4+,CD4+/CD8+were lower than those in the control group,with statistical significance(P＜0.05).Serum MST4 and HSP70 levels in mild group,moderate group and severe group were increased successively,with statistical significance(P＜0.05).Correlation analysis showed that serum MST4 and HSP70 were positively correlated with CD8+(P＜0.05),and negatively correlated with PLT,CD3+,CD4+,CD4+/CD8+(P＜0.05).The disease course,serum MST4 and HSP70 of ITP children in the poor prognosis group were higher than those in the good prognosis group,and the differences were statistically significant(P＜0.05).Logistic regression analysis showed that the course of disease(OR=1.579,P＜0.001),serum MST4(OR=1.451,P＜0.001)and serum HSP70(OR=1.442,P＜0.001)were independent risk factors af-fecting the prognosis of children with ITP.The area under the curve of serum MST4 and HSP70 combined in the assessment of poor prognosis of ITP children was larger than that of serum MST4 and HSP70,and the difference was statistically significant(Z=4.568,4.672,both P＜0.001).Conclusion The elevated serum MST4 and HSP70 levels in children with ITP are related to the severity of the disease and cellular immune function.The combination of the two has a high evaluation value for the prognosis of children with ITP.

Traditional mass measurement methods are not applicable in microgravity environments,and the main challenge for in-orbit body mass measurement technology based on inertial principles is to address the random errors brought about by the weightless environment.These include additional torques due to shifts in the center of mass,nonlinear accelerations due to non-rigid human bodies,mechanical energy consumption due to organ vibrations,and random vibrations of the measurement device itself.To address the above difficulties,the project proposes a technical scheme based on the principle of linear acceleration,designs and constructs a ground-specific air-floating experimental and simulation platform,studies key data such as motion trajectory,acceleration change,and vibration frequency amplitude during the mass measurement process,and simulates the changes in the center of mass and random vibrations of the human body in a weightless environment.The project has designed an adjustable posture bracket to adapt to changes in the center of mass,enhance body restraint,and greatly reduce shaking;it has also developed an integrated four-bar linkage motion guidance mechanism,high-precision integrated photoelectric distance measurement,and modular motion constant force measurement device to ensure the accurate measurement of acceleration and constant force data.The product has undergone simulation calculations,ground human applicability tests,and in-orbit applicability verification in the space station.Ground test results show that the device achieves a body mass measurement accuracy better than 0.5%,and the dispersion is better than 0.38%;after flight mission verification and evaluation,the in-orbit body mass measurement dispersion is less than 0.4%,which is superior to the SLAMMD,a mass measurement device of the same principle on the International Space Station,and is at the forefront internationally,achieving accurate body mass measurement.

Background/Aims: Metabolic dysfunction-associated steatohepatitis (MASH) is a significant risk factor for gallstone formation, but mechanisms underlying MASH-related gallstone formation remain unclear. Golgi membrane protein 1 (GOLM1) participates in hepatic cholesterol metabolism and is upregulated in MASH. Here, we aimed to explore the role of GOLM1 in MASH-related gallstone formation. Methods: The UK Biobank cohort was used for etiological analysis. GOLM1 knockout (GOLM1-/-) and wild-type (WT) mice were fed with a high-fat diet (HFD). Livers were excised for histology and immunohistochemistry analysis. Gallbladders were collected to calculate incidence of cholesterol gallstones (CGSs). Biles were collected for biliary lipid analysis. HepG2 cells were used to explore underlying mechanisms. Human liver samples were used for clinical validation. Results: MASH patients had a greater risk of cholelithiasis. All HFD-fed mice developed MASH, and the incidence of gallstones was 16.7% and 75.0% in GOLM1-/- and WT mice, respectively. GOLM1-/- decreased biliary cholesterol concentration and output. In vivo and in vitro assays confirmed that GOLM1 facilitated cholesterol efflux through upregulating ATP binding cassette transporter subfamily G member 5 (ABCG5). Mechanistically, GOLM1 translocated into nucleus to promote osteopontin (OPN) transcription, thus stimulating ABCG5-mediated cholesterol efflux. Moreover, GOLM1 was upregulated by interleukin-1β (IL-1β) in a dose-dependent manner. Finally, we confirmed that IL-1β, GOLM1, OPN, and ABCG5 were enhanced in livers of MASH patients with CGSs. Conclusions In MASH livers, upregulation of GOLM1 by IL-1β increases ABCG5-mediated cholesterol efflux in an OPN-dependent manner, promoting CGS formation. GOLM1 has the potential to be a molecular hub interconnecting MASH and CGSs.

Background/Aims: Metabolic dysfunction-associated steatohepatitis (MASH) is a significant risk factor for gallstone formation, but mechanisms underlying MASH-related gallstone formation remain unclear. Golgi membrane protein 1 (GOLM1) participates in hepatic cholesterol metabolism and is upregulated in MASH. Here, we aimed to explore the role of GOLM1 in MASH-related gallstone formation. Methods: The UK Biobank cohort was used for etiological analysis. GOLM1 knockout (GOLM1-/-) and wild-type (WT) mice were fed with a high-fat diet (HFD). Livers were excised for histology and immunohistochemistry analysis. Gallbladders were collected to calculate incidence of cholesterol gallstones (CGSs). Biles were collected for biliary lipid analysis. HepG2 cells were used to explore underlying mechanisms. Human liver samples were used for clinical validation. Results: MASH patients had a greater risk of cholelithiasis. All HFD-fed mice developed MASH, and the incidence of gallstones was 16.7% and 75.0% in GOLM1-/- and WT mice, respectively. GOLM1-/- decreased biliary cholesterol concentration and output. In vivo and in vitro assays confirmed that GOLM1 facilitated cholesterol efflux through upregulating ATP binding cassette transporter subfamily G member 5 (ABCG5). Mechanistically, GOLM1 translocated into nucleus to promote osteopontin (OPN) transcription, thus stimulating ABCG5-mediated cholesterol efflux. Moreover, GOLM1 was upregulated by interleukin-1β (IL-1β) in a dose-dependent manner. Finally, we confirmed that IL-1β, GOLM1, OPN, and ABCG5 were enhanced in livers of MASH patients with CGSs. Conclusions In MASH livers, upregulation of GOLM1 by IL-1β increases ABCG5-mediated cholesterol efflux in an OPN-dependent manner, promoting CGS formation. GOLM1 has the potential to be a molecular hub interconnecting MASH and CGSs.

Background/Aims: Metabolic dysfunction-associated steatohepatitis (MASH) is a significant risk factor for gallstone formation, but mechanisms underlying MASH-related gallstone formation remain unclear. Golgi membrane protein 1 (GOLM1) participates in hepatic cholesterol metabolism and is upregulated in MASH. Here, we aimed to explore the role of GOLM1 in MASH-related gallstone formation. Methods: The UK Biobank cohort was used for etiological analysis. GOLM1 knockout (GOLM1-/-) and wild-type (WT) mice were fed with a high-fat diet (HFD). Livers were excised for histology and immunohistochemistry analysis. Gallbladders were collected to calculate incidence of cholesterol gallstones (CGSs). Biles were collected for biliary lipid analysis. HepG2 cells were used to explore underlying mechanisms. Human liver samples were used for clinical validation. Results: MASH patients had a greater risk of cholelithiasis. All HFD-fed mice developed MASH, and the incidence of gallstones was 16.7% and 75.0% in GOLM1-/- and WT mice, respectively. GOLM1-/- decreased biliary cholesterol concentration and output. In vivo and in vitro assays confirmed that GOLM1 facilitated cholesterol efflux through upregulating ATP binding cassette transporter subfamily G member 5 (ABCG5). Mechanistically, GOLM1 translocated into nucleus to promote osteopontin (OPN) transcription, thus stimulating ABCG5-mediated cholesterol efflux. Moreover, GOLM1 was upregulated by interleukin-1β (IL-1β) in a dose-dependent manner. Finally, we confirmed that IL-1β, GOLM1, OPN, and ABCG5 were enhanced in livers of MASH patients with CGSs. Conclusions In MASH livers, upregulation of GOLM1 by IL-1β increases ABCG5-mediated cholesterol efflux in an OPN-dependent manner, promoting CGS formation. GOLM1 has the potential to be a molecular hub interconnecting MASH and CGSs.