Protein Secretion Research Articles

Quercetin protects against sepsis-associated encephalopathy by inhibiting microglia-neuron crosstalk via the CXCL2/CXCR2 signaling pathway

BackgroundSepsis-associated encephalopathy (SAE) is a common brain lesion associated with severe sepsis, for which ferroptosis is a key driving factor. Thus, suppressing ferroptosis may be an effective strategy for treating SAE. Quercetin (QUE) is a natural flavonoid with antioxidant and anti-inflammatory properties. However, its role on ferroptosis in SAE remains unclear. PurposeThis study aimed to investigate the mechanism underlying the therapeutic effect of QUE on cecal ligation perforation (CLP)-induced SAE. MethodsIn vivo and in vitro SAE models were established using CLP and lipopolysaccharide (LPS), respectively. Both models underwent pre-treatment with QUE. ResultsQUE attenuated CLP-induced symptoms, including temperature changes, neurological severity scores, learning and memory dysfunction, inflammatory cytokine release, and microglia activation in SAE mice, and inhibited LPS-induced microglia recruitment and chemotaxis. Bioinformatics analysis revealed that the C-X-C motif chemokine ligand 2 (CXCL2)/C-X-C motif chemokine receptor 2 (CXCR2) axis may play a key role in QUE-mediated protection against SAE. Moreover, QUE significantly inhibited LPS-induced CXCL2 up-regulation and protein secretion from microglia. Recombinant mouse-derived CXCL2 (rmCXCL2) promoted inflammatory cytokine secretion, NF-κB/NLRP3 signaling activation, and microglia recruitment and chemotaxis. Furthermore, rmCXCL2 induced ferroptosis in mouse hippocampal neurons, as evidenced by elevated malondialdehyde levels, decreased glutathione levels, excessive iron uptake, and altered ferroptosis-related protein expression. The CXCR2 antagonist SB225002 effectively reversed the effects of rmCXCL2. Importantly, in vivo experiments further demonstrated that the therapeutic effect of QUE on SAE was inhibited by rmCXCL2. ConclusionThis study demonstrates that CXCL2 secreted by activated microglia mediates microglia self-activation and induces hippocampal neuronal ferroptosis via CXCR2 and that QUE exerts neuroprotective effects on SAE by blocking interactions between microglia and neurons via CXCL2/CXCR2 pathway inhibition.

Effects and Mechanisms of the Xianhecao-Huanglian Drug Pair on Autophagy-Mediated Intervention in Acute Inflammatory Bowel Disease via the JAK2/STAT3 Pathway

To explore the effects and mechanisms of the Xianhecao-Huanglian drug pair on autophagy-mediated intervention in acute inflammatory bowel disease (IBD) via the JAK2/STAT3 pathway. The study examined the underlying mechanisms of action of Xianhecao (APL) and Huanglian (CR) using a mouse model of dextran sodium sulfate (DSS)-induced acute inflammatory bowel disease (IBD) and in an in vitro model of IBD induced by lipopolysaccharide (LPS). The assessment of the therapeutic efficacy of the Xianhecao-Huanglian drug combination in a mouse model of IBD caused by DSS included the following parameters: Assessment of weight loss or gain. Measurement of the disease activity index (DAI). Assessment of histological damage. Determination of organ index. Measurement of colon length. Ascertain the levels of inflammatory cytokines in the intestinal tissues and serum of mice. Immunohistochemistry (IHC) for the measurement of tight junction protein concentrations in the colon mucosa, including ZO-1, claudin-1, and occludin. Measurement of mucin levels, specifically Mucin 2 (Muc2). Hematoxylin and eosin (HE) staining for the observation of histopathological alterations in colonic tissues. Examining the effect on goblet cells using periodic acid-Schiff (PAS) labeling. Application of Western blot and immunofluorescence techniques for the detection of autophagy-related markers in colonic tissues and proteins associated with the JAK2/STAT3 pathway. A cell inflammation model of IBD was induced through LPS stimulation, and a serum containing the Xianhecao-Huanglian drug pair (referred to as ACHP-DS) was formulated. Cell viability, anti-proinflammatory cytokines, tight junction proteins, mucins, autophagy-related markers, and the JAK2/STAT3 signaling pathway were assessed. The Xianhecao-Huanglian drug pair significantly ameliorated the symptoms and survival quality of acute IBD mice, reducing the disease activity index score, raising MUC2 secretion and tight junction protein expression to improve the integrity of the intestinal barrier, and preserving goblet cell function; thus, protecting the intestines. It effectively restrained triggering the signaling pathway that involves JAK2 and STAT3, leading to the suppression of inflammation and amelioration of colonic inflammation damage. Additionally, it induced autophagy in mouse colonic tissues.The in vitro experiments demonstrated that the Xianhecao-Huanglian drug combination enhanced the viability of LOVO and NCM460 cells when exposed to LPS stimulation. Furthermore, it suppressed the production of inflammatory cytokines such as IL-6, IL-1β, as well as TNF-α, whilst increasing the production of IL-10, ZO-1, along with MUC2. These effects collectively led to the alleviation of inflammation and the restoration of mucosal integrity. The results were consistent with what was shown in the in vivo trial. Moreover, the medication demonstrated effectiveness in reducing JAK2 along with STAT3 phosphorylation levels in the LPS-induced inflammatory model of IBD cells. The intervention with either the Xianhecao-Huanglian drug combination-containing serum or the JAK2/STAT3 pathway inhibitor AG490 reversed the pro-inflammatory effects and increased autophagy levels in the LPS-stimulated cells. The Xianhecao-Huanglian drug combination modulates the JAK2/STAT3 pathway, leading to the induction of autophagy, which serves as an intervention for IBD.

Mechanisms of adaptive resistance in Phytobacter sp. X4 to antimony stress under anaerobic conditions

Sb(III) oxidation by microorganisms plays a key role in the geochemical cycling of antimony and is effective for bioremediation. A previously discovered novel Sb(III)-oxidizing bacteria, Phytobacter sp. X4, was used to elucidate the response patterns of extracellular polypeptides (EPS), antioxidant system, electron transfer and functional genes to Sb(III) under anaerobic conditions. The toxicity of Sb(III) was mitigated by increasing Sb(III) oxidation capacity, and the EPS regulated the content of each component by sensing the concentration of Sb(III). High Sb(III) concentrations induced significant secretion of proteins and polysaccharides of EPS, and polysaccharides were more important. Functional groups including hydroxyl, carboxyl and amino groups on the cell surface adsorbed Sb(III) to block its entry. Hydroxyl radicals and hydrogen peroxide were involved in anaerobic Sb(III) oxidation, as revealed by changes in the antioxidant system and electron spin resonance (EPR) techniques. qPCR confirmed that proteins concerning nitrate and antimony transfer, antimony resistance and antioxidant system were regulated by Sb(III) concentration, and the synergistic cooperation of multiple proteins conferred high antimony resistance to X4. The adaptive antimony resistance mechanism of Phytobacter sp. X4 under anaerobic conditions was revealed, which also provides a reference value for bioremediation method of antimony contamination in anaerobic environment.

Diagnostic value of serum Clara cell secretory protein level in an experimental blunt chest trauma model

Objective: Blunt chest trauma is a significant clinical problem leading to injury of the lungs that may be fatal. Experimental blunt chest trauma is well established in animal models. This study aimed to investigate whether Clara cell secretory protein (CC16) can be a biomarker in an experimentally created blunt chest trauma model. Material and Methods: A total of 30 rabbits were used in our study. A modified bilateral blunt thoracic trauma model was used to produce different levels of lung contusion. We divided the rabbits into four groups according to the energy level at which blunt thoracic trauma was applied. Blood samples were taken from the control and trauma groups to evaluate CC16 levels at 0, 12, and 24 hours. Results: The CC16 levels measured at the start of the experiment were significantly lower in the control and low-energy groups compared to the medium- and high-energy groups (p =.002). While there was a significant difference in CC16 levels measured at the 12th hour (p =.004), no significant difference was found among the groups at the 24th hour. Upon analyzing the change in CC16 levels over time within the groups, we observed that CC16 levels decreased from 0–12 hours and subsequently increased after the 12th hour. Histopathologically, we observed that the level of contusion increased in proportion to the severity of trauma across the different groups. Conclusion: With the designed platform, we created a reproducible experimental model of pulmonary contusion from blunt thoracic trauma in rabbits. Increased levels of CC16 following a lung contusion could serve as a foundation for clinical decision-making. Thus, CC16 has the potential to serve as a rapid and simple biochemical indicator for acute traumatic lung injury.

Cobalt exposure and pulmonary function reduction in chronic obstructive pulmonary disease patients: the mediating role of club cell secretory protein

BackgroundCobalt (Co) is a metal which is widely used in the industrial production. The previous studies found the toxic effects of environmental Co exposure on multiple organs. However, the correlation of blood Co concentration with lung function was inconsistent in patients with chronic obstructive pulmonary disease (COPD).MethodsAll 771 stable COPD patients were recruited. Peripheral blood and clinical information were collected. The levels of blood Co and serum CC16 were measured.ResultsCross-sectional study suggested that the level of blood Co was inversely and dose-dependently related to lung function parameters. Each 1 ppm elevation of blood Co was related to 0.598 L decline in FVC, 0.465 L decline in FEV1, 6.540% decline in FEV1/FVC%, and 14.013% decline in FEV1%, respectively. Moreover, higher age, enrolled in winter, current-smoking, higher smoking amount, and inhaled corticosteroids prominently exacerbated the negative correlation between blood Co and lung function. Besides, serum CC16 content was gradually reduced with blood Co elevation in COPD patients. Besides, serum CC16 was positively correlated with lung function, and inversely related to blood Co. Additionally, decreased CC16 substantially mediated 11.45% and 6.37% Co-triggered downregulations in FEV1 and FEV1%, respectively.ConclusionBlood Co elevation is closely related to the reductions of pulmonary function and serum CC16. CC16 exerts a significantly mediating role of Co-related to pulmonary function decrease among COPD patients.

Lipid synthesis, triggered by PPARγ T166 dephosphorylation, sustains reparative function of macrophages during tissue repair

Macrophages may acquire a reparative phenotype that supports tissue repair and remodeling in response to tissue injury. However, the metabolic requirements underpinning this process are incompletely understood. Here, we show that posttranslational modification (PTM) of PPARγ regulates lipid synthesis in response to wound microenvironmental cues and that metabolic rewiring orchestrates function of reparative macrophages. In injured tissues, repair signaling leads to decreased macrophage PPARγ threonine 166 (T166) phosphorylation, which results in a partially active PPARγ transcriptional program comprised of increased binding activity to the regulator regions of lipid synthesis-associated genes, thereby increased lipogenesis. The accumulated lipids serve as signaling molecules, triggering STAT3-mediated growth factor expression, and supporting the synthesis of phospholipids for the expansion of the endoplasmic reticulum (ER), which is required for protein secretion. Genetic or pharmacological inhibition of PPARγ T166 phosphorylation promotes the reparative function of macrophages and facilitates tissue regeneration. In summary, our work identifies PPARγ T166-regulated lipid biosynthesis as an essential pathway for meeting the anabolic demands of the activation and function of macrophages and provides a rationale for potential therapeutic targeting of tissue repair.

Emergence of antibiotic-specific Mycobacterium tuberculosis phenotypes during prolonged treatment of mice.

A major challenge in tuberculosis (TB) therapeutics is that antibiotic exposure leads to changes in the physiologic state of M. tuberculosis (Mtb) which may enable the pathogen to withstand treatment. While antibiotic-treated Mtb have been evaluated in short-term in vitro experiments, it is unclear if and how long-term in vivo treatment with diverse antibiotics with varying treatment-shortening activity (sterilizing activity) affect Mtb physiologic states differently. Here, we used SEARCH-TB, a pathogen-targeted RNA-sequencing platform, to characterize the Mtb transcriptome in the BALB/c high-dose aerosol infection mouse model following 4-week treatment with three sterilizing and three non-sterilizing antibiotics. Certain transcriptional changes were concordant among most antibiotics, including decreased expression of genes associated with protein synthesis and metabolism, and the induction of certain genes associated with stress responses. However, the magnitude of this concordant response differed between antibiotics. Sterilizing antibiotics rifampin, pyrazinamide, and bedaquiline generated a more quiescent Mtb state than did non-sterilizing antibiotics isoniazid, ethambutol, and streptomycin, as indicated by decreased expression of genes associated with translation, transcription, secretion of immunogenic proteins, metabolism, and cell wall synthesis. Additionally, we identified distinguishing transcriptional effects specific to each antibiotic, indicating that different mechanisms of action induce distinct patterns of cellular injury. In addition to elucidating Mtb physiologic changes associated with antibiotic stress, this study demonstrates the value of SEARCH-TB as a highly granular pharmacodynamic assay that reveals antibiotic effects that are not apparent based on culture alone.

A sex-specific homologue of waprin is essential for embryonic development in the red flour beetle, Tribolium castaneum.

Waprin, a WAP (Whey acidic protein) domain-containing extracellular secretory protein, is widely known for its antibacterial properties. In this study, a waprin homologue (Tc_wapF) expressing in a female-specific manner was identified in Tribolium castaneum, through the analysis of sex-specific transcriptomes. Developmental- and tissue-specific profiling revealed the widespread expression of Tc_wapF in adult female tissues, particularly in the ovary, gut and fatbody. This female-specific expression of Tc_wapF is not regulated by the classical sex-determination cascade of T. castaneum, as we fail to get any attenuation in Tc_wapF transcript levels in Tcdsx and Tctra (key players of sex determination cascade of T. castaneum) knockdown females. RNA interference-mediated knockdown of Tc_wapF in females led to the non-hatching of eggs laid by these females, suggesting the crucial role of Tc_wapF in the embryonic development in T. castaneum. This is the first report on the identification of a sex-specific waprin homologue in an insect and its involvement in embryonic development. Future investigations on the functional conservation of insect waprins and their mechanistic role in embryonic development can be exploited for improving pest management strategies.

SCYL2-related autosomal recessive neurodevelopmental disorders: Arthrogryposis multiplex congenita-4 and beyond?

SCY1-like protein 2 (SCYL2) is a member of the SCY1-like pseudokinase family which regulates secretory protein trafficking. It plays a crucial role in the nervous system by suppressing excitotoxicity in the developing brain. Scyl2 knockout mice have excess prenatal mortality and survivors show severe neurological dysfunction. Bi-allelic loss-of-function (LOF) variants in SCYL2 were recently associated with arthrogryposis multiplex congenita-4 (AMC4) following the report of 6 individuals from two consanguineous unrelated families. The AMC4 phenotype described included severe arthrogryposis, corpus callosum agenesis, epilepsy and frequently, early death. We describe here two additional similarly affected individuals with AMC4, including one diagnosed in the prenatal period, with bi-allelic LOF variants in SCYL2, and two individuals homozygous for missense variants in the protein kinase domain of SCYL2 and presenting with developmental delay only. Our study confirms the association of SCYL2 with AMC4 and suggests a milder phenotype can occur, extending the phenotypic spectrum of autosomal recessive SCYL2-related disorders.

Protein disulfide isomerase PDI8 is indispensable for parasite growth and associated with secretory protein processing in Toxoplasma gondii.

Apicomplexans, a phylum of intracellular parasites, encompass various zoonotic pathogens, including Plasmodium, Cryptosporidium, Toxoplasma, and Babesia, causing a significant economic burden on human populations. These parasites exhibit hypersensitivity to disruptions in endoplasmic reticulum (ER) redox homeostasis, necessitating the presence of ER-localized thioredoxin (Trx) superfamily proteins, particularly protein disulfide isomerase (PDI), for proper oxidative folding. However, the functional characteristics of ER-localized PDI proteins in Toxoplasma gondii remain largely unexplored. In this study, we identified two ER-localized proteins, namely, TgPDI8 and TgPDI6, and demonstrated the indispensable role of TgPDI8 in parasite survival. Through a comprehensive multi-omics analysis, we elucidated the crucial role of TgPDI8 in the processing of secretory proteins in T. gondii. Additionally, we introduced a novel ER-anchored TurboID method to label and identify canonical secretory proteins in T. gondii. This research opens up new avenues for understanding oxidative folding and the secretory pathway in apicomplexan parasites, laying the groundwork for future advancements in antiparasitic drug development.

Calcium-binding protein TgpCaBP regulates calcium storage of the zoonotic parasite Toxoplasma gondii.

Toxoplasma gondii, the causative parasite of toxoplasmosis, is an apicomplexan parasite that infects warm-blooded mammals. The ability of the calcium-binding proteins (CBPs) to transport large amounts of Ca2+ appears to be critical for the biological activity of T. gondii. However, the functions of some members of the CBP family have not yet been deciphered. Here, we characterized a putative CBP of T. gondii, TgpCaBP (TGME49_229480), which is composed of four EF-hand motifs with Ca2+-binding capability. TgpCaBP was localized in the cytosol and ER of T. gondii, and parasites lacking the TgpCaBP gene exhibited diminished abilities in cell invasion, intracellular growth, egress, and motility. These phenomena were due to the abnormalities in intracellular Ca2+ efflux and ER Ca2+ storage, and the reduction in motility was associated with a decrease in the discharge of secretory proteins. Therefore, we propose that TgpCaBP is a Ca2+ transporter and signaling molecule involved in Ca2+ regulation and parasitization in the hosts.IMPORTANCECa2+ signaling is essential in the development of T. gondii. In this study, we identified a calcium-binding protein in T. gondii, named TgpCaBP, which actively regulates intracellular Ca2+ levels in the parasite. Deletion of the gene coding for TgpCaBP caused serious deficits in the parasite's ability to maintain a stable intracellular calcium environment, which also impaired the secretory protein discharged from the parasite, and its capacity of gliding motility, cell invasion, intracellular growth, and egress from host cells. In summary, we have identified a novel calcium-binding protein, TgpCaBP, in the zoonotic parasite T. gondii, which is a potential therapeutic target for toxoplasmosis.

Use of proteomics to elucidate characteristics of Cronobacter sakazakii under mild heat stress

Cronobacter sakazakii is an opportunistic pathogen known for causing severe diseases. Mild heat treatment is commonly used in food processing, however, the pathogenic characteristics and underlying mechanisms of Cronobacter sakazakii strains remain poorly understood. In this study, we found that mild heat stress (MHS) at 52 °C can induce several deleterious effects in Cronobacter sakazakii, including damage to the cell wall, genomic DNA breakage, and misfolding of cytoplasmic proteins. These conditions lead to a decreased survival ability under acid, desiccation, and osmotic stress; a reduction in biofilm formation; and diminished motility. Notably, surviving C. sakazakii cells retain their pathogenicity, causing significant intestinal damage in newborn mice. This damage is characterized by epithelial sloughing and disruption of the intestinal structure. Tandem mass tag (TMT)-based proteomics identified 736 proteins with differential abundance across C. sakazakii strains subjected to mild heat stress, highlighting adaptations in biofilm formation, motility, and stress tolerance. Key regulatory changes were observed in phospholipid metabolism and protein synthesis, which underpin this complex stress response. This data illustrates a sophisticated balance between environmental adaptability and pathogenic potential. The metabolic and pathogenic responses of C. sakazakii to mild heat stress are closely linked to its phospholipid metabolism and the production of secretory proteins, both crucial for its virulence and reliant on membrane transport. This complex interplay emphasizes the need to understand these mechanisms to develop effective control strategies.

Genetic Code Expansion in Shewanella oneidensis MR-1 Allows Site-Specific Incorporation of Bioorthogonal Functional Groups into a c-Type Cytochrome.

Genetic code expansion has enabled cellular synthesis of proteins containing unique chemical functional groups to allow the understanding and modulation of biological systems and engineer new biotechnology. Here, we report the development of efficient methods for site-specific incorporation of structurally diverse noncanonical amino acids (ncAAs) into proteins expressed in the electroactive bacterium Shewanella oneidensis MR-1. We demonstrate that the biosynthetic machinery for ncAA incorporation is compatible and orthogonal to the endogenous pathways of S. oneidensis MR-1 for protein synthesis, maturation of c-type cytochromes, and protein secretion. This allowed the efficient synthesis of a c-type cytochrome, MtrC, containing site-specifically incorporated ncAA in S. oneidensis MR-1 cells. We demonstrate that site-specific replacement of surface residues in MtrC with ncAAs does not influence its three-dimensional structure and redox properties. We also demonstrate that site-specifically incorporated bioorthogonal functional groups could be used for efficient site-selective labeling of MtrC with fluorophores. These synthetic biology developments pave the way to expand the chemical repertoire of designer proteins expressed in S. oneidensis MR-1.

Removal of signal peptide variants by cation exchange chromatography: A case study

Signal peptide (SP) is required for secretion of recombinant proteins and typically cleaved by signal peptidase at its C-region to generate the mature proteins. Miscleavage of the SP is reported occasionally, resulting in a truncated- or elongated-terminal sequence. In the present work, we demonstrated that cation exchange (CEX) chromatography is an effective means for removing SP variants with a case study. With the selected resin/conditions, the chromatographic performance is comparable between runs performed at the low end and high end of load density and elution range. The procedure described in this work can be used as a general approach for resin selection and optimization of chromatographic conditions to remove byproducts that bind more strongly than the product to the selected resin.

Uncovering key steps in FGF12 cellular release reveals a common mechanism for unconventional FGF protein secretion

FGF12 belongs to a subfamily of FGF proteins called FGF homologous factors (FHFs), which until recently were thought to be non-signaling intracellular proteins. Our recent studies have shown that although they lack a conventional signal peptide for secretion, they can reach the extracellular space, especially under stress conditions. Here, we unraveled that the long “a” isoform of FGF12 is secreted in a pathway involving the A1 subunit of Na(+)/K(+) ATPase (ATP1A1), Tec kinase and lipids such as phosphatidylinositol and phosphatidylserine. Further, we showed that the short “b” isoform of FGF12, which binds ATP1A1 and phosphatidylserine less efficiently, is not secreted from cells. We also indicated regions in the FGF12a protein sequence that are crucial for its secretion, including N-terminal fragment and specific residues, and proposed that liquid-liquid phase separation may be important in this process. Our results strongly suggest that the mechanism of this process is very similar for all unconventionally secreted FGF proteins.

Generation of Insulin-Producing Cells from Canine Bone Marrow-Derived Mesenchymal Stem Cells: A Preliminary Study.

Cell-based therapy using insulin-producing cells (IPCs) is anticipated as an alternative treatment option to insulin injection or pancreatic islet transplantation for the treatment of diabetes mellitus in both human and veterinary medicine. Several protocols were reported for the differentiation of mesenchymal stem cells (MSCs) into IPCs; to date, glucose-responsive IPCs have only been obtained from canine adipose tissue-derived MSCs (cAD-MSCs), but not from canine bone marrow-derived MSCs (cBM-MSCs). Therefore, this study aims to generate in vitro glucose-responsive IPCs from cBM-MSCs using two differentiation protocols: a two-step protocol using trichostatin (TSA) and a three-step protocol using mercaptoethanol to induce pancreatic and duodenal homeobox gene 1 (PDX-1) expression. A single experiment was carried out for each protocol. BM-MSCs from one dog were successfully cultured and expanded. Cells exposed to the two-step protocol appeared rarely grouped to form small clusters; gene expression analysis showed a slight increase in PDX-1 and insulin expression, but no insulin protein production nor secretion in the culture medium was detected either under basal conditions or following glucose stimulation. Conversely, cells exposed to the three-step protocol under a 3D culture system formed colony-like structures; insulin gene expression was upregulated compared to undifferentiated control and IPCs colonies secreted insulin in the culture medium, although insulin secretion was not enhanced by high-glucose culture conditions. The single experiment results suggest that the three-step differentiation protocol could generate IPCs from cBM-MSCs; however, further experiments are needed to confirm these data. The ability of IPCs from cBM- MSCs to produce insulin, described here for the first time, is a preliminary interesting result. Nevertheless, the IPCs' unresponsiveness to glucose, if confirmed, would affect its clinical application. Further studies are necessary to establish a differentiation protocol in this perspective.

Extracellular production of azurin by reusable magnetic Fe3O4 nanoparticle-immobilized Pseudomonas aeruginosa

Azurin, found in the periplasm of Pseudomonas aeruginosa, has garnered significant attention as a potential anticancer agent in recent years. High-level secretion of proteins into the culture medium, offers a significant advantage over periplasmic or cytoplasmic expression. In this study, for the first time, P. aeruginosa cells were immobilized with magnetic nanoparticles (MNPs) to ensure effective, simple and quick separation of the cells and secretion of periplasmic azurin protein to the culture medium. For this purpose, polyethyleneimine-coated iron oxide (Fe3O4@PEI) MNPs were synthesized and MNPs containing Fe up to 600 ppm were found to be non-toxic to the bacteria. The highest extracellular azurin level was observed in LB medium compared to peptone water. The cells immobilized with 400 ppm Fe-containing MNPs secreted the highest protein. Lastly, the immobilized cells were found suitable for azurin secretion until the sixth use. Thus, the magnetic nanoparticle immobilization method facilitated the release of azurin as well as the simple and rapid separation of cells. This approach, by facilitating protein purification and enabling the reuse of immobilized cells, offers a cost-effective means of protein production, reducing waste cell formation, and thus presents an advantageous method.

Prognostic significance of HS2ST1 expression in patients with hepatocellular carcinoma

BackgroundHeparan sulfate 2-O-sulfotransferase 1 (HS2ST1) catalyzes the sulfation of glucuronic acid residues in heparan sulfate proteoglycans, enabling these proteoglycans to interact with numerous ligands within tumor microenvironments. However, the prognostic role of HS2ST1 expression in cancer remains unclear.ObjectiveThis investigated HS2ST1 expression levels and their prognostic significance in various cancer types, demonstrated the prognostic value of HS2ST1 expression in hepatocellular carcinoma (HCC) patients, and identified molecular signatures associated with HS2ST1 expression.MethodsHS2ST1 expression and patient survival data from The Cancer Genome Atlas (TCGA) datasets were analyzed using the Gene Expression Profiling Interactive Analysis (GEPIA) portal. We obtained gene expression and clinicopathological information on HCC patients from the TCGA and the Japan and France International Cancer Genome Consortium (ICGC) databases and performed survival analyses. We also examined relevant protein networks, differentially expressed genes, gene set enrichments, and tumor immune microenvironment features associated with HS2ST1 expression.ResultsHS2ST1 exhibited higher expression in eight tumor types compared with normal tissues and was associated with poor prognoses in five tumors, including HCC. HS2ST1 status correlated with poor prognosis in two ICGC HCC cohorts. Elevated HS2ST1 expression in HCC tumors was associated with signaling pathways involved in cell cycle progression, protein secretion, and mTORC1 signaling. Moreover, HS2ST1 expression levels were inversely correlated with immune cell infiltration in the tumor microenvironment.ConclusionOur study elucidates the prognostic significance of HS2ST1 expression in HCC patients and provides insights into the potential roles of HS2ST1 in signaling pathways and the tumor microenvironment.

UBL3 overexpression enhances EV-mediated Achilles protein secretion in conditioned media of MDA-MB-231 cells

Cancer cells communicate within the tumor microenvironment (TME) through extracellular vesicles (EVs), which act as crucial messengers in intercellular communication, transporting biomolecules to facilitate cancer progression. Ubiquitin-like 3 (UBL3) facilitates protein sorting into small EVs as a post-translational modifier. However, the effect of UBL3 overexpression in EV-mediated protein secretion has not been investigated yet. This study aimed to investigate the effect of UBL3 overexpression in enhancing EV-mediated Achilles protein secretion in MDA-MB-231 (MM) cells by a dual-reporter system integrating Akaluc and Achilles tagged with Ubiquitin where self-cleaving P2A linker connects Akaluc and Achilles. MM cells stably expressing Ubiquitin-Akaluc-P2A-Achilles (Ubi-Aka/Achi) were generated. In our study, both the bioluminescence of Ubiquitin-Akaluc (Ubi-Aka) and the fluorescence of Achilles secretion were observed. The intensity of Ubi-Aka was thirty times lower, while the Achilles was four times lower than the intensity of corresponding cells. The ratio of Ubi-Aka and Achilles in conditioned media (CM) was 7.5. They were also detected within EVs using an EV uptake luciferase assay and fluorescence imaging. To investigate the effect of the UBL3 overexpression in CM, Ubi-Aka/Achi was transiently transfected into MM-UBL3-KO, MM, and MM-Flag-UBL3 cells. We found that the relative fluorescence expression of Achilles in CM of MM-UBL3-KO, MM, and MM-Flag-UBL3 cells was 30 %, 28 %, and 45 %, respectively. These findings demonstrated that UBL3 overexpression enhances EV-mediated Achilles protein secretion in CM of MM cells. Targeting UBL3 could lead to novel therapies for cancer metastasis by reducing the secretion of pro-metastatic proteins, thereby inhibiting disease progression.

Perfused In Vitro Intestine Tissue Model to Evaluate the Role of Stromal and Immune Cells in Epithelial Response to Inflammatory Cues and Drug Therapies.

We establish an in vitro perfusion intestinal tissue bioreactor system tailored to study drug responses related to inflammatory bowel disease (IBD). The system includes key components including multiple human intestinal cell types (colonoids, myofibroblasts, and macrophages), a three-dimensional (3D) intestinal architecture, and fluid flow. Inclusion of myofibroblasts resulted in increased secretion of cytokines such as glypican-1 (GCP-1), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin 1-α (IL-1α), whereas inclusion of macrophages resulted in increased secretion of monocyte chemoattractant proteins (MCPs) demonstrating a significant role of both stromal and immune cell types in intestinal inflammation. The system is responsive to drug treatments, as reflected in the reduction of pro-inflammatory cytokine production in tissue in some treatment scenarios. While future studies are needed to evaluate more nuanced responses in an IBD context, the present study demonstrates the ability to establish a 3D intestinal model with multiple relevant cell types and flow that is responsive to both inflammatory cues and various drug treatment options.