Objective To investigate the gene expression and regulatory mechanisms of mouse embryonic fibroblasts (MEFs) under inflammatory conditions, aiming to elucidate the role of MEFs in inflammatory responses and provide a foundation for discovering anti-inflammatory drugs that act by modulating MEF function. Methods MEFs cultured in vitro were divided into the following groups: lipopolysaccharides (LPS)-treated group, inflammatory conditioned medium (CM)-treated group, and control group, which were treated with LPS, CM, and equal volume solvent, respectively. Transcriptome sequencing was used to analyze the effects of two stimuli on gene expression profile of MEFs. Real time fluorescence quantitative PCR (RT-qPCR) was employed to verify the transcription levels of highly expressed genes of MEFs induced by CM. ELISA was performed to determine the concentrations of cytokines in cell supernatants. Finally, the regulatory effects of CM on the activation of signaling pathways in MEFs were analyzed by immunoblotting. Results Transcriptome analysis showed that both LPS and CM induced the transcription of a large number of genes in MEFs. Compared with LPS, CM potentiated the mRNA transcription of some acute phase proteins, inflammatory cytokines, chemokines, matrix metalloproteinases (MMP), prostaglandin synthetases, and colony-stimulating factors. The transcriptome analysis was verified by RT-qPCR. The results of ELISA showed that CM treatment significantly increased the secretion of interleukin 6 (IL-6), C-C motif chemokine ligand (CCL2), and C-X-C motif chemokine ligand (CXCL1) by MEFs compared with LPS. Mechanism study showed that both LPS and CM induced the phosphorylation of nuclear factor-κB p65 (NF-κB p65), p38 mitogen-activated protein kinase (p38 MAPK), extracellular regulated protein kinases 1/2 (ERK1/2), and TANK-binding kinase (TBK) in MEFs, and CM strongly stimulated the phosphorylation of signal transducer and activator of transcription 3 (STAT3) in MEFs. Conclusion Both LPS and CM can induce transcription and protein secretion of various inflammation-related genes in MEFs. CM can partly enhance LPS-induced activation of MEFs, and the mechanism may be related to the enhancement effect of CM on the activation STAT3 signaling pathway.
Animals ; Fibroblasts/immunology* ; Mice ; Lipopolysaccharides/pharmacology* ; Inflammation/metabolism* ; Signal Transduction/drug effects* ; Gene Expression Regulation/drug effects* ; Cytokines/genetics* ; Culture Media, Conditioned/pharmacology* ; Cells, Cultured

Objective To investigate how culture duration affects the expression of immune membrane proteins in human monocyte-derived dendritic cells (DCs) and their exosomes (DEXs). Methods Human monocytes were induced with recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4) to differentiate into DCs and were subsequently matured with tumor necrosis factor α(TNF-α). Exosomes were isolated by ultracentrifugation, and DEXs were identified by transmission electron microscopy and Amnis imaging flow cytometry, which were also used to quantify the expression of immune membrane proteins on DCs and DEXs. Results On the 10th day of culture, DCs displayed high surface expression of CD11c, CD80, CD86, major histocompatibility complex class I (MHC-I), and MHC-II. Expression peaked at day 18(CD11c: 78.66%±20.33%, CD80: 76.41%±10.02%, CD86: 96.43%±0.43%, MHC-I: 84.71%±2.96%, MHC-II: 80.01%±7.03%). After day 24, the overall expression showed a declining trend, with statistically significant differences observed for all markers except CD80 and MHC-II. By day 30, 80% of the DCs still expressed CD80, CD86, and MHC-II. The expression of immune membrane proteins on DEX surfaces also reached its peak on day 18, followed by an overall decline with prolonged culture time, with statistically significant differences observed for all markers except CD80. Correlation analysis revealed a significant positive relationship between the expression levels of immune membrane proteins on DC and DEX surfaces (CD11c: r=0.98; CD80: r=0.65; CD86: r=0.82; MHC-I: r=0.86; MHC-II: r=0.93). Conclusion Human monocyte-derived DCs in vitro express high expression of immune membrane proteins and maintain stable expression over a specific period. The exosomes secreted by these cells similarly demonstrate high surface expression of immune membrane proteins, with temporal trends aligned with those of the parent DCs.
Humans ; Dendritic Cells/immunology* ; Exosomes/immunology* ; Monocytes/metabolism* ; Cells, Cultured ; Time Factors ; B7-1 Antigen/metabolism* ; Membrane Proteins/immunology* ; Cell Culture Techniques/methods* ; B7-2 Antigen/metabolism* ; Cell Differentiation ; CD11c Antigen/metabolism* ; Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology*

OBJECTIVE: Blood culture remains the gold standard for diagnosing bloodstream infections. Clinical laboratories must ensure the quality of blood culture processes from receipt to obtaining definitive results. We examined laboratory analytical indicators associated with positive blood culture results. METHODS: Blood cultures collected from Peking Union Medical College Hospital between January 1, 2020, and December 31, 2022, were retrospectively analyzed. The mode of transportation (piping logistics delivery vs. staff), source of blood cultures (outpatient/emergency department vs. inpatient department), rotation of personnel, and time of reception (8:00-19:59 vs. 20:00-07:59) were compared between blood culture-positive and -negative results. RESULTS: Between 2020 and 2022, the total positive rate of blood culture was 8.07%. The positive rate of blood cultures in the outpatient/emergency department was significantly higher than that in the inpatient department (12.46% vs. 5.83%; P < 0.0001). The time-to-detection of blood cultures was significantly affected by the delivery mode and personnel rotation. The blood culture positive rate of the total pre-analytical time within 1 h was significantly higher than that within 1-2 h or > 2 h ( P < 0.0170). CONCLUSION Laboratory analytical indicators such as patient source, transportation mode, and personnel rotation significantly impacted the positive detection rate or time of blood culture.
Blood Culture/statistics & numerical data* ; Humans ; Retrospective Studies ; Emergency Service, Hospital/statistics & numerical data*

N-dodecanoyl-l-homoserine lactone (C12-HSL) is a signaling molecule that mediates bacterial quorum sensing, regulating bacterial population behaviors. This study investigated the effects of C12-HSL on the isolation and cultivation of gut microbiota, with the goal of enriching the diversity and number of cultivable bacterial strains from the mouse gut microbiota. Using a culture medium supplemented with C12-HSL, we isolated and cultivated bacterial strains from mouse intestinal contents, obtaining a total of 235 isolates. Preliminary identification based on the 16S rRNA gene revealed 54 bacterial species, including 4 potential new species, 4 potential new genera and 1 potential new family. Compared with the previously established mouse gut microbial biobank (mGMB), this study newly identified 42 bacterial species, enhancing the diversity of the strain library. Statistical analysis showed that the proportion of Gram-negative bacteria, particularly those belonging to Proteobacteria, isolated by this method was significantly higher than that obtained by conventional isolation and cultivation methods without the addition of C12-HSL. Subsequent cultivation experiments with one of the newly discovered bacterial species indicated that exogenous C12-HSL at 20-200 μmol/L significantly promoted the growth of this species, while higher concentrations of C12-HSL significantly reduced the cell density of this bacterium. This work confirms that quorum sensing molecules, such as C12-HSL, can enhance the growth, isolation, and cultivation of Gram-negative bacteria in the gut within a specific concentration range. Although the mechanism by which C12-HSL promotes the growth of gut bacterial strains requires further investigation, the findings of this study provide new insights into the targeted isolation, cultivation, and regulation of gut microbiota using bacterial quorum sensing signal molecules.
Animals ; Mice ; Acyl-Butyrolactones/pharmacology* ; Gastrointestinal Microbiome/drug effects* ; Quorum Sensing ; Gram-Negative Bacteria/classification* ; Intestines/microbiology* ; RNA, Ribosomal, 16S/genetics* ; Culture Media

Organoids are three-dimensional (3D) cellular structures formed through the differentiation and self-organization of pluripotent stem cells or tissue-derived cells, showing considerable potential in the research on disease mechanism, personalized medicine, and developmental biology. However, the development of organoids is limited by the complex composition, batch-to-batch variations, and immunogenicity of basement-membrane matrix in the current culture system, which hinders the clinical translation and in vivo applications of organoids. Hydrogels are highly hydrated 3D polymer network materials, with modifiable mechanical and biochemical properties by engineering, representing an ideal alternative to basement-membrane matrix. This article reviews the research progress in engineered hydrogels with defined composition currently used in organoid culture. We introduce the structural characteristics and engineering design considerations of hydrogels, emphasize the latest research progress and specific application cases, and discuss the future development of these engineered hydrogels, provide valuable insights for the further advancement and optimization of engineered hydrogels for organoid.
Hydrogels/chemistry* ; Organoids/cytology* ; Tissue Engineering/methods* ; Humans ; Animals ; Pluripotent Stem Cells/cytology* ; Cell Culture Techniques, Three Dimensional/methods* ; Tissue Scaffolds

As prepubertal boys do not yet produce spermatozoa, they cannot rely on sperm cryopreservation for fertility preservation before gonadotoxic therapy, such as high-dose alkylating agents or radiotherapy in the case of childhood cancers. According to the current guidelines, cryopreservation of testicular biopsies containing spermatogonial stem cells (SSCs) may be proposed to high-risk patients for potential later therapeutic use to fulfill the patients' wish for a biological child. One promising technique for human in vitro spermatogenesis and in vitro propagation of human SSCs is microfluidic (MF) culture, in which cells or tissues are subjected to a continuous flow of medium. This provides exact control over such parameters as nutrient content and gradients, as well as the removal of waste metabolites. While MF has been shown to maintain tissues and cell populations of organs for longer than conventional in vitro culture techniques, it has not been widely used for testicular in vitro culture. MF could advance human testicular in vitro culture and is also applicable to reprotoxicity studies. This review summarizes the findings and achievements of testis-on-chip (ToC) setups to date and discusses the benefits and limitations of these for spermatogenesis in vitro and toxicity assessment.
Humans ; Male ; Spermatogenesis/physiology* ; Testis/cytology* ; Cryopreservation ; Cell Culture Techniques/methods* ; Microfluidics/methods* ; Animals

Osteosarcoma (OS), chondrosarcoma (CS), and Ewing sarcoma (ES) represent primary malignant bone tumors and pose significant challenges in oncology research and clinical management. Conventional research methods, such as two-dimensional (2D) cultured tumor cells and animal models, have limitations in recapitulating the complex tumor microenvironment (TME) and often fail to translate into effective clinical treatments. The advancement of three-dimensional (3D) culture technology has revolutionized the field by enabling the development of in vitro constructed bone tumor models that closely mimic the in vivo TME. These models provide powerful tools for investigating tumor biology, assessing therapeutic responses, and advancing personalized medicine. This comprehensive review summarizes the recent advancements in research on 3D tumor models constructed in vitro for OS, CS, and ES. We discuss the various techniques employed in model construction, their applications, and the challenges and future directions in this field. The integration of advanced technologies and the incorporation of additional cell types hold promise for the development of more sophisticated and physiologically relevant models. As research in this field continues to evolve, we anticipate that these models will play an increasingly crucial role in unraveling the complexities of malignant bone tumors and accelerating the development of novel therapeutic strategies.
Bone Neoplasms/pathology* ; Humans ; Osteosarcoma/pathology* ; Tumor Microenvironment ; Sarcoma, Ewing/pathology* ; Chondrosarcoma/pathology* ; Animals ; Cell Culture Techniques/methods* ; Cell Culture Techniques, Three Dimensional/methods* ; Cell Line, Tumor

Macrophages derived from the human THP-1 cell line have been widely used as substitutes for primary macrophages in various macrophage-related studies. However, difficulties still exist in establishing THP-1 macrophage models. This research presents techniques for generating different phenotypes of activated macrophages derived from THP-1 cells by introducing specific stimuli and provides some potential markers to confirm each type of activated macrophage. It is hoped to provide novel and useful methods for scientific research and to help researchers explore this field more intuitively and effectively.
Humans ; Macrophages/physiology* ; THP-1 Cells ; Cell Culture Techniques/methods* ; Macrophage Activation ; Cell Polarity ; Cell Differentiation ; Phenotype ; Cell Line

Xerostomia (dry mouth) is frequently experienced by patients treated with radiotherapy for head and neck cancers or with Sjögren's syndrome, with no permanent cure existing for this debilitating condition. To this end, in vitro platforms are needed to test therapies directed at salivary (fluid-secreting) cells. However, since these are highly differentiated secretory cells, the maintenance of their differentiated state while expanding in numbers is challenging. In this study, the efficiency of three reversible thermo-ionically crosslinked gels: (1) alginate-gelatin (AG), (2) collagen-containing AG (AGC), and (3) hyaluronic acid-containing AG (AGHA), to recapitulate a native-like environment for human salivary gland (SG) cell expansion and 3D spheroid formation was compared. Although all gels were of mechanical properties comparable to human SG tissue (~11 kPa) and promoted the formation of 3D spheroids, AGHA gels produced larger (>100 cells/spheroid), viable (>93%), proliferative, and well-organized 3D SG spheroids while spatially and temporally maintaining the high expression of key SG proteins (aquaporin-5, NKCC1, ZO-1, α-amylase) for 14 days in culture. Moreover, the spheroids responded to agonist-induced stimulation by increasing α-amylase secretory granules. Here, we propose alternative low-cost, reproducible, and reversible AG-based 3D hydrogels that allow the facile and rapid retrieval of intact, highly viable 3D-SG spheroids.
Humans ; Hydrogels/chemistry* ; Acinar Cells/cytology* ; Spheroids, Cellular/cytology* ; Salivary Glands/cytology* ; Gelatin/chemistry* ; Collagen/chemistry* ; Alginates/chemistry* ; Cell Culture Techniques/methods* ; Hyaluronic Acid/chemistry* ; Cell Proliferation ; Cell Survival ; Cells, Cultured

Human naïve pluripotent stem cells (PSCs) hold great promise for embryonic development studies. Existing induction and culture strategies for these cells, heavily dependent on MEK inhibitors, lead to widespread DNA hypomethylation, aberrant imprinting loss, and genomic instability during extended culture. Here, employing high-content analysis alongside a bifluorescence reporter system indicative of human naïve pluripotency, we screened over 1,600 chemicals and identified seven promising candidates. From these, we developed four optimized media-LAY, LADY, LUDY, and LKPY-that effectively induce and sustain PSCs in the naïve state. Notably, cells reset or cultured in these media, especially in the LAY system, demonstrate improved genome-wide DNA methylation status closely resembling that of pre-implantation counterparts, with partially restored imprinting and significantly enhanced genomic stability. Overall, our study contributes advancements to naïve pluripotency induction and long-term maintenance, providing insights for further applications of naïve PSCs.
Humans ; DNA Methylation/drug effects* ; Genomic Instability ; Pluripotent Stem Cells/metabolism* ; Cell Culture Techniques/methods* ; Cells, Cultured