Co-culture System Research Articles

Co-culture system of breast cancer and normal cells to investigate inflammation: using doxorubicin encapsulated in adipose-derived exosomes.

Doxorubicin (DOX) chemotherapy for breast cancer is an effective treatment option, but it also has disadvantages. Exosomes (EXOs) have safely and successfully transported DOX and reduced its adverse effects; however, its use is still being explored. In this study, a co-culture system of malignant and non-malignant breast cells was used to generate an in vitro model reflecting the in vivo cellular microenvironment, and the effects of this treatment were investigated by examining inflammatory genes. Extracellular matrices (EXOs) were extracted from mesenchymal stem cells derived from human adipose tissue by ultracentrifugation. Later, Western blotting, dynamic light scattering (DLS) and transmission electron microscopy methods were used to examine the properties of the EXO. DOX was encapsulated in the EXOs by sonication and the loading rate was measured by spectrophotometry. In the current study, a co-culture system was used to investigate the cytotoxic effects of free DOX and DOX encapsulated in EXOs (EXO-DOX) on various breast cell lines, including MCF-7, MCF-10A, MDA-MB-231, and A-MSC. Additionally, the expression levels of inflammatory cytokines (IL-1β, IL-6, IL-10, and TNF-α) were examined. Methylthiazolyldiphenyl-tetrazolium bromide assay demonstrated that free DOX showed the highest cytotoxicity against MCF-10A cells, followed by MCF-7 cells. Conversely, EXO-DOX indicated a greater effect on MCF-7 cells and had a lower IC50 compared to MDA-MB-231 cells. Free DOX significantly downregulated the expression of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α), particularly in MCF-7 and MCF-10A cells, while concurrently upregulating IL-10 expression. EXO-DOX induced a more significant alteration in cytokine expression than the control and free DOX treatment groups. The co-culture system revealed a synergistic effect of free DOX on cancer cells while simultaneously mitigating the toxic effects of DOX on normal cells. This study suggests that EXO-DOX has promising potential as a targeted drug delivery system that could potentially improve therapeutic efficacy and minimize off-target toxicity.

Depletion of Tregs from CD4+ CAR-Tcells enhances the tumoricidal effect of CD8+ CAR-Tcells in anti-CD19 CAR-T therapy.

Chimeric antigen receptor T (CAR-T) cell therapy, which targets CD19 for hematological malignancies, represents a breakthrough in cancer immunotherapy. However, some patients may develop resistance to CAR-T treatment, underscoring the importance of optimizing CAR-T design to enhance responsiveness. Here, we investigated the impact of different subpopulations in anti-CD19 CAR-T cells on the tumoricidal effect. Different populations of anti-CD19 CAR-T cells were isolated by magnetic-activated cell sorting (MACS). Their lytic activities on the acute lymphocytic leukemia cell line SUP-B15 and diffuse large B-cell lymphoma EB-3 cell line were examined in a co-culture system. The anti-tumorigenic outcome of different CAR-T cell compositions was evaluated in a xenograft mouse model of EB-3 cells. CD8+CAR-T cells exhibited the most potent tumoricidal activity against SUP-B15 and EB-3 cells. Additionally, CD4+ T helper cells enhanced the lytic effects of CD8+ CAR-T cells by increasing the availability of interleukin-2 (IL-2). Depleting CD25+Treg (T regulatory) cells from CD4+CAR-T population further augmented the tumoricidal activity of CD8+CAR-T cells by preventing IL-2 deprivation. Consistently, in vivo experiments demonstrated that the CD4+CD25+ Treg population dampened the antitumor activity of CD8+CAR-T cells, while depletion of Tregs from CD4+CAR-T cells enhanced the tumoricidal effect. These findings emphasize the potential role of CAR Treg cells in therapeutic resistance, suggesting that the depletion of Tregs in the anti-CD19 CAR-T population may serve as a strategy to augment the anticancer effect of CD8+CAR-T cells.

FRK exerts oncogenic effects by targeting NQO2 via exosomal miR-9-3p to regulate mitochondrial function.

The role of Fyn-related kinase (FRK) in promoting tumor progression and metabolism in non-small cell lung cancer (NSCLC) has been demonstrated in our earlier study, and here we further explored whether exosome could serve as a key player in the relevant regulatory mechanism. Exosomes were isolated from the culture medium of FRK-knockout (KO) cells and co-cultured with NSCLC cells, showing negative effects on cell proliferation, metastasis, metabolism, and mitochondrial function. Exosomal miR-9-3p was selected as an intermediate messenger through microRNA (miRNA) sequencing. The miR-9-3p inhibitor and exosome inhibitor GW4869 were then applied in the co-culture system to verify the contribution of exosomal miR-9-3p to cell malignant phenotype and mitochondrial function. Moreover, NQO2, a potential target of exosomal miR-9-3p, was also suggested to be involved in the regulation of mitochondrial functional status. In brief, this study revealed a novel molecular mechanism by which FRK promotes the malignant progression of NSCLC by targeting NQO2 via exosomal miR-9-3p to strengthen mitochondrial function.

A synergistic fermentation system of probiotics with low-cost and high butyric acid production: Lactiplantibacillus plantarum and Clostridium tyrobutyricum

Butyric acid plays a significant role in maintaining body health, and thus the research on cost-effective and efficient biological conversion strategies for butyric acid production holds great importance. This study utilized the mutual interactions between prebiotics and multiple probiotic strains to target increasing the butyric acid yield in a co-fermentation system. Briefly, xylan, an inexpensive biomass material, was used as a prebiotic to screen lactic acid bacteria that capable of being promoted for proliferation and metabolism in its presence. Subsequently, the interaction between the screened lactic acid bacteria and a butyric acid-producing strain (Clostridium tyrobutyricum) was utilized to enhance butyric acid production. The results showed that xylan significantly improved the proliferation and lactic acid metabolizing ability of Lactiplantibacillus plantarum C0502. Whole-genome analysis revealed that L. plantarum carries at least four distinct enzyme genes related to the hydrolysis and utilization of xylan. Co-cultivation of L. plantarum with C. tyrobutyricum demonstrated that the C. tyrobutyricum was able to effectively convert lactic and acetic acids into butyric acid. Furthermore, the addition of xylan into this co-culture system yielded a remarkable butyric acid production of up to 5.01 ± 0.04 g/L, which is 4.58 times higher than the yield obtained from the monoculture of C. tyrobutyricum in reinforced Clostridium medium. The results of this study suggested that the co-culture system of xylan, L. plantarum, and C. tyrobutyricum has the potential to significantly enhance butyric acid production while markedly reduce the production cost. This has immense prospects for practical applications.

Mincle Maintains M1 Polarization of Macrophages and Contributes to Renal Aging Through the Syk/NF-κB Pathway.

Kidney is a classic organ undergoing senescence, and chronic inflammation has an important effect in cellular senescence. Mincle has been shown to be vital for maintaining the M1 phenotype of macrophages, but its role in regulating renal aging has yet to be explored. Young (2 months of age) and old (24 months of age) mice were used to analyze the changes of kidney damage during natural aging. Mice were subcutaneously injected with D-galactose (D-gal) to establish a renal aging model, and miR-6948-3p mimic and Mincle siRNA were administered via the tail vein every 3 days. Aged kidney and experimental aging kidney were characterized by decreased renal function and structural damage, and upregulated expression of senescence-related proteins and SPAP components. The ratio of M1 macrophages was increased in the aged kidney, and Mincle accumulated in the aged kidney macrophages. Administration of miR-6948-3p mimic or Mincle siRNA alleviated D-gal-induced renal senescence. LPS was used to induce M1 polarization of bone marrow-derived macrophages, and a coculture system of M1 macrophages and mouse renal tubular epithelial cells (TCMK-1) was established. Mincle was upregulated in LPS-induced M1 macrophages in vitro, and silencing Mincle in M1 macrophages attenuated M1 macrophage-induced TCMK-1 cell senescence. Mechanistically, Mincle was regulated by miR-6948-3p and maintained the M1 phenotype of macrophages through the Syk/NF-κB pathway. In conclusion, Mincle, posttranscriptionally suppressed by miR-6948-3p, modulated renal senescence by maintaining the phenotype of M1 macrophages through the Syk/NF-κB pathway.

Major diet of common carp (Cyprinus carpio L.) over different developmental stages in rice-field: agroecological interactions between fishes and rice in Sichuan, China, based on DNA metabarcoding approach

The rice-fish co-culture system (RFS) is a traditional cooperative farming model employed in southern China that can achieve doubling the harvest of rice (Oryza sp.) and fish. Most studies on RFS have focused on ecological mechanisms, benefits, ecosystem services, and agroecosystem functions; however, little is known about the baseline dietary composition in common carp of RFS, particularly across different developmental stages. In this study, we applied DNA metabarcoding of invertebrates (COI) and plants (Rbcl) to investigate the natural diets of common carp (Cyprinus carpio) across three developmental stages: juvenile (May), sub-adult (July), and adult (September). The animal-derived diets of common carp were dominated by prey from the orders Diptera, Lepidoptera, and Hemiptera, and the main plant-derived food items belonged to the families Poaceae, Araceae, and Hydrocharitaceae. We examined variations in the dietary compositions of common carp across three developmental stages to capture adaptations to seasonal changes in food resource availability. Additionally, we detected insect pests (species from the genera Macrosteles and Mythimna) and weeds (Eleusine indica, Alternanthera philoxeroides, Mazus japonicus, and Poa annua) in the diets of common carp, confirming the ecological benefits of common carp in rice fields by reducing insect pests and weeds. Characterizing the dietary composition and variation of common carp over developmental stages contributes to our understanding of its foraging ecology, dietary niche, and dynamics of trophic interactions, and provides critical information for evaluating the ecological benefits of common carp in RFS.

Deciphering potential molecular mechanisms in clear cell renal cell carcinoma based on the ubiquitin-conjugating enzyme E2 related genes: Identifying UBE2C correlates to infiltration of regulatory T cells.

Renal clear cell carcinoma (ccRCC) is a highly aggressive and common form of kidney cancer, with limited treatment options for advanced stages. Recent studies have highlighted the importance of the ubiquitin-proteasome system in tumor progression, particularly the role of ubiquitin-conjugating enzyme E2 (UBE2) family members. However, the prognostic significance of UBE2-related genes (UBE2RGs) in ccRCC remains unclear. In this study, bulk RNA-sequencing and single-cell RNA-sequencing data from ccRCC patients were retrieved from the Cancer Genome Atlas and Gene Expression Omnibus databases. Differential expression analysis was performed to identify UBE2RGs associated with ccRCC. A combination of 10 machine learning methods was applied to develop an optimal prognostic model, and its predictive performance was evaluated using area under the curve (AUC) values for 1-, 3-, and 5-year overall survival (OS) in both training and validation cohorts. Functional enrichment analyses of gene ontology and Kyoto Encyclopedia of Genes and Genomes were conducted to explore the biological pathways involved. Correlation analysis was conducted to investigate the association between the risk score and tumor mutational burden (TMB) and immune cell infiltration. Immunotherapy and chemotherapy sensitivity were assessed by immunophenoscore and tumor immune, dysfunction, and exclusion scores to identify potential predictive significance. In vitro, knockdown of the key gene UBE2C in 786-O cells by specific small interfering RNA to validate its impact on apoptosis, migration, cell cycle, migration, invasion of tumor cells, and induction of regulatory T cells (Tregs). Analysis of sc-RNA revealed that UBE2 activity was significantly upregulated in malignant cells, suggesting its role in tumor progression. A three-gene prognostic model comprising UBE2C, UBE2D3, and UBE2T was constructed by Lasoo Cox regression and demonstrated robust predictive accuracy, with AUC values of 0.745, 0.766, and 0.771 for 1-, 3-, and 5-year survival, respectively. The model was validated as an independent prognostic factor in ccRCC. Patients in the high-risk group had a worse prognosis, higher TMB scores, and low responsiveness to immunotherapy. Additionally, immune infiltration and chemotherapy sensitivity analyses revealed that UBE2RGs are associated with various immune cells and drugs, suggesting that UBE2RGs could be a potential therapeutic target for ccRCC. In vitro experiments confirmed that the reduction of UBE2C led to an increase in apoptosis rate, as well as a decrease in tumor cell invasion and metastasis abilities. Additionally, si-UBE2C cells reduced the release of the cytokine Transforming Growth Factor-beta 1 (TGF-β1), leading to a decreased ratio of Tregs in the co-culture system. This study presents a novel three-gene prognostic model based on UBE2RGs that demonstrates significant predictive value for OS, immunotherapy, and chemotherapy in ccRCC patients. The findings underscore the potential of UBE2 family members as biomarkers and therapeutic targets in ccRCC, warranting further investigation in prospective clinical trials.

SMURF1 leads to the β-catenin signaling-mediated progression of esophageal squamous carcinoma by losing PATZ1-induced CCNG2 transcription

Cyclin G2 (CCNG2), a known inhibitor of cell cycle progression, has been identified as a suppressor for the canonical β-catenin pathway. This study explores the impact of CCNG2 on β-catenin activity and malignant characteristics of esophageal squamous cell carcinoma (ESCC) cells, and the mechanism behind CCNG2 dysregulation. In ESCC tissues and cells, CCNG2 was under-expressed and associated with poor clinical outcomes, whereas β-catenin showed an opposite trend. Inducing CCNG2 overexpression in ESCC cells led to a reduction in β-catenin levels, which in turn suppressed proliferation, cell cycle progression, migration, invasion, stemness, and tumorigenesis. Additionally, it enhanced the cytotoxicity and proliferation of T cells in co-culture systems. However, these beneficial effects were negated by the Wnt signaling agonist BML-284. Furthermore, PATZ1 was found as a transcription factor promoting CCNG2 transcription. However, the PATZ1 protein in ESCC cells was degraded by SMURF1. Silencing of SMURF1 restored CCNG2 expression and inhibited β-catenin, thereby suppressing the malignant phenotype of ESCC cells and reducing T cell exhaustion. Yet, these effects were blocked by further silencing of PATZ1. In summary, this research demonstrates that SMURF1 activates β-catenin signaling by suppressing the PATZ1/CCNG2 axis, thereby promoting the progression of ESCC.

M2 macrophage-derived exosomes promote cell proliferation, migration and EMT of non-small cell lung cancer by secreting miR-155-5p.

Tumor-associated macrophages (TAMs) are a type of highly plastic immune cells in the tumor microenvironment (TME), which can be classified into two main phenotypes: classical activated M1 macrophages and alternatively activated M2 macrophages. As previously reported, M2-polarized TAMs play critical role in promoting the progression of non-small cell lung cancer (NSCLC) via secreting exosomes, but the detailed mechanisms are still largely unknown. In the present study, the THP-1 monocytes were sequentially induced into M0 and M2-polarized macrophages, and the exosomes were obtained from M0 (M0-exos) and M2 (M2-exos) polarized macrophages, respectively, and co-cultured with NSCLC cells (H1299 and A549) to establish the exosomes-cell co-culture system in vitro. As it was determined by MTT assay, RT-qPCR and Transwell assay, in contrast with the M0-exos, M2-exos significantly promoted cell proliferation, migration and epithelial-mesenchymal transition (EMT) process in NSCLC cells. Next, through screening the contents in the exosomes, it was verified that miR-155-5p was especially enriched in the M2-exos, and M2-exos enhanced cancer aggressiveness and tumorigenesis in in vitro NSCLC cells and in vivo xenograft tumor-bearing mice models via delivering miR-155-5p. The detailed molecular mechanisms were subsequently elucidated, and it was found that miR-155-5p bound with HuR to increase the stability and expression levels of VEGFR2, which further activated the tumor-promoting PI3K/Akt/mTOR signal pathway, and M2-exos-enhanced cancer progression in NSCLC cells were apparently suppressed by downregulating VEGFR2 and PI3K inhibitor LY294002 co-treatment. Taken together, M2-polarized TAMs secreted miR-155-5p-containing exosomes to enhanced cancer aggressiveness of NSCLC by activating the VEGFR2/PI3K/Akt/mTOR pathway in a HuR-dependent manner.

TGF-β3 Restrains Osteoclastic Resorption Through Autophagy

While TGF-β3 promoted defect healing in a primate baboon skull defect model and patients, it remains unclear whether TGF-β3 affects the formation of osteoclasts and bone resorption between osteogenesis and osteolysis. Analysis of the full transcriptome of hPDLSCs (human periodontal ligament stem cells) revealed that the expression of RANKL was significantly up-regulated after TGF-β3 treatment during osteogenesis, which suggests its involvement in clock-controlled autophagy in bone metabolism. TRAP staining and bone resorption lacunae were used to assess the osteoclasts formed from RANKL-induced differentiated BMMs. During osteoclast differentiation, the characteristics of autophagy regulated by TGF-β3 were observed in BMMs through MDC staining, transmission electron microscopy, and LC3 immunofluorescence. The expression of related genes and proteins were detected on the sixth day in mCherry-EGFP-LC3B lentivirus-transfected BMMs using RT-qPCR and WB. Finally, a trans-well co-culture system was used to evaluate the effects of osteogenic differentiated hPDLSCs treated with TGF-β3 on the osteoclastic differentiation of BMMs. The results showed 10 ng/mL of TGF-β3 significantly suppressed osteoclastic differentiation and bone resorption in BMMs (p < 0.05 vs. RANKL). In particular, TGF-β3 augments the expression of LC3-II to stimulate autophagy, consequently restraining osteoclastic resorption. These findings provide a molecular basis and are beneficial to illustrate the potential druggability of TGF-β3 in osteoporotic diseases.

Macrophage subtypes inhibit breast cancer proliferation in culture.

Macrophages are a highly plastic cell type that adopt distinct subtypes and functional states depending on environmental cues. These functional states can vary widely, with distinct macrophages capable of displaying opposing functions. We sought to understand how macrophage subtypes that exist on two ends of a spectrum influence the function of other cells. We used a co-culture system with primary human macrophages to probe the effects of macrophage subtypes on breast cancer cell proliferation. Our studies revealed a surprising phenotype in which both macrophage subtypes inhibited cancer cell proliferation compared to cancer cells alone. Of particular interest, using two different proliferation assays with two different breast cancer cell lines, we showed that differentiating macrophages into a "pro-tumor" subtype inhibited breast cancer cell proliferation. These findings are inconsistent with the prevailing interpretation that "pro-tumor" macrophages promote cancer cell proliferation and suggest a re-evaluation of how these interpretations are made. [Media: see text].

Effects of a Vegetable Eel Co-Culture System on the Soil Ammonia-Oxidizing Microbial Community

(1) Background: A vegetable eel co-culture system is an economically efficient way of agricultural cultivation, which can have an impact on the soil microbial environment and play a pivotal role in the soil nutrient cycle, but there is little research on its impact on soil ammonia-oxidizing microorganisms. (2) Methods: NovaSeq platform sequencing was employed to investigate the richness, structure, and diversity of soil ammonia-oxidizing microbial communities, exploring the effects of a vegetable eel co-culture system on soil nitrogen cycling. Four different planting treatments were set up: unfertilized without vegetable eel (CCK), fertilized without vegetable eel (CRT), unfertilized with vegetable eel (ICK), and fertilized with vegetable eel (IRT). (3) Results: A vegetable eel co-culture system significantly increased soil pH and decreased bulk density under fertilization conditions. The soil nitrification potential rate was enhanced by a vegetable eel co-culture system to an average of 26.3%. A vegetable eel co-culture system significantly altered the community structure of all ammonia-oxidizing microorganisms, with a significant increase in the richness and diversity of ammonia-oxidizing bacteria (AOB) and comammox clade-A, while fertilization significantly increased the diversity of all ammonia-oxidizing microbial communities. Structural equation modeling (SEM) analysis showed that the main environmental factors affecting the structure of the ammonia-oxidizing microbial community were nitrate and total nitrogen. The number of amoA genes in AOB and comammox clade-B was significantly positively correlated with the soil potential N nitrification rate (PNR), which played a leading role in the nitrification of alkaline vegetable soil. The network analysis revealed that a vegetable eel co-culture system improved the modularity of AOB and comammox clade-B by 13.14% and 5.66%. (4) Conclusions: This study showed that the vegetable eel co-culture system stimulated the evolution of ammonia-oxidizing microbial communities by changing the physicochemical properties, which in turn promoted the soil nitrification reaction.

Enhanced anti-inflammatory effects and metabolic profiles of cyanidin-3-glucoside via nanoliposomal encapsulation in Caco-2 and RAW 264.7 co-culture system

Cyanidin-3-glucoside (C3G) has been found to prevent/treat intestinal disease and maintain gut homeostasis. Numerous studies have proved that nanoliposomes can improve the absorption and utilization of food nutrients. However, the impacts of C3G nanoliposomes (C3G-NL) are still unkown. This study investigated the effects of cyanidin-3-glucoside nanoliposomes (C3G-NL) on intestinal inflammation and permeability using a Caco-2/RAW264.7 co-culture model. ELISA and qPCR results showed that C3G-NL reduced pro-inflammatory markers, including TNF-α, IL-6, IL-8, cyclooxygenase-2, and inducible nitric oxide synthase, while inhibiting the NF-κB/MAPK pathway. C3G-NL also improved intestinal barrier integrity by increasing transepithelial electrical resistance and upregulating tight junction proteins (zonula occludens-1, occludin, claudin-1). Additionally, C3G-NL enhanced C3G metabolism, leading to the formation of intermediary metabolites like chalcone and dihydroflavonols, which contributed to the synthesis of other anthocyanins (delphinidin, peonidin, petunidin, malvidin, and pelargonidin). Overall, C3G-NL helps mitigate inflammation and restore tight junction integrity via metabolic regulation.

Directional and Strain-Specific Interaction Between Lactobacillus plantarum and Staphylococcus aureus

The interaction between Lactobacillus plantarum and Staphylococcus aureus strains FRI-1169 and MN8, two original isolated strains from menstrual toxic shock syndrome (mTSS) cases, is a key focus for developing non-antibiotic strategies to control S. aureus-related infections. While the antagonistic effects of Lactobacilli species on S. aureus through mechanisms like organic acid and bacteriocin production are known, the molecular dynamics of these interactions remain underexplored. This study employs a proteomic approach to analyze the interactions between L. plantarum WCFS1 and S. aureus strains, FRI-1169 and MN8, during co-culture. We profiled differentially expressed proteins (DEPs) found in the spent media and cytosols of both bacteria, revealing distinct directional and strain-specific responses. The findings demonstrate that L. plantarum exerts a more pronounced effect on S. aureus, with more DEPs and upregulated proteins, while S. aureus showed fewer DEPs and more downregulated proteins. These strain-specific interactions highlight the complex metabolic and regulatory adjustments between these bacterial species. This research provides valuable insights into the molecular mechanisms of Lactobacillus-S. aureus antagonism and underscores the potential of proteomic analysis as a powerful tool for studying bacterial dynamics in co-culture systems.

The effect of c-Myc on regulating the immune-related ligands in Y subtype small cell lung cancer through histone deacetylase 1

Objective: To explore the effect and mechanism of c-Myc on regulating the expression of immune-related ligands in Y subtype small-cell lung cancer (SCLC) characterized by high expression of immune-related molecules. Methods: The Y subtype SCLC cell line H196 was randomly divided into the control group, c-Myc inhibitor 10058-F4 group, histone deacetylase 1 (HDAC1) inhibitor pyroxamide group, and 10058-F4 plus pyroxamide group. The co-culture system with NK-92MI cells was used to determine the effect of H196 cells on the function of natural killer (NK) cells. Western Blotting and co-immunoprecipitation assays were used to detect the effect of c-Myc on class Ⅰ HDAC, and flow cytometry was used to detect the regulatory effect of c-Mycon CD47, programmed cell death ligand 1 (PD-L1), and CD155, which are highly expressed immune checkpoints in Y subtype SCLC, and major histocompatibility complex classⅠ-related chains A and (MICA/B), which is a poorly expressed immune-activating ligand in SCLC, and the role of HDAC. Chromatin immunoprecipitation (ChIP) assay and real-time quantitative polymerase chain reaction (RT-qPCR) were used to determine the regulatory mechanism of c-Myc-HDAC1 on MICA/B expression. Results: Inhibition of c-Myc decreased the mortality of H196 cells in the co-culture system and down-regulated the expression of MICA/B. Compared with the NK+H196 group [(42.54±2.47)%], the proportion of cells killed by NK-92MI cells in the NK+H196+10058-F4 group was lower [(28.48±3.38)%, P＜0.001]. The mean fluorescence intensity (MFI) of MICA/B on the cells in the 10058-F4 group (36.40±0.82) was lower than that in the control group (91.23±8.60, P＜0.001). And c-Myc could bind to HDAC1, whose protein level was up-regulated by 10058-F4 while the mRNA level was not. Compared with the cells in the control group (90.10±4.91), the MFI of MICA/B on the cells in the pyroxamide group was significantly increased (145.70±5.86, P＜0.001), and the MFI of MICA/B on the cells in the 10058-F4+pyroxamide group (54.60±2.88) was significantly increased compared with the cells in the 10058-F4 group (35.97±1.60, P＜0.001). The percentage of MICA promoter gene fragments in the c-Myc antibody precipitation group (0.125±0.037) was significantly higher than that in the IgG group (0.000 8±0.000 3, P=0.004). MICB had a similar trend, suggesting that the c-Myc-HDAC1 complex could bind to the promoter region of MICA/B. The MFI of CD47 on the cells in the 10058-F4 group (60.07±0.21) was significantly lower than cells in the control group (70.27±1.37, P＜0.001), but the MFIs of PD-L1 (13.50±0.61) and CD155 (829.70±41.19) were significantly higher than those on the cells in the control group (9.23±0.94, P＜0.01; 496.00±4.36, P＜0.001, respectively). Conclusions: c-Myc may promote the expression of MICA/B and CD47 in Y subtype SCLC cells by binding and inhibiting HDAC1, while it may also be involved in inhibiting the expression of PD-L1 and CD155 in SCLC cells.

Mouse Small Intestinal Organoid Cultures.

The intestinal epithelium is a highly dynamic and self-renewing tissue that is crucial for maintaining gut homeostasis. It can be cultured in vitro from isolated crypts to form three-dimensional (3D) intestinal organoids. These organoids have the ability to proliferate and differentiate into various epithelial cell lineages, offering a more physiologically relevant model compared to traditional two-dimensional (2D) culture systems. Mesenchymal cells, located near epithelial cells, regulate epithelial behavior through paracrine signaling and provide structural support. Building on recent advances in the biology of epithelial and mesenchymal cells, we have developed a coculture system that integrates intestinal organoids with mesenchymal cells. In this system, intestinal organoids are cultured in direct or indirect contact with mesenchymal cells, allowing for the simulation of signal exchange and interactions within the in vivo-like microenvironment. This coculture system not only preserves the 3D architecture of the organoids but also enhances their physiological relevance by introducing cellular complexity. The system is capable of long-term maintenance and is adaptable to a wide range of experimental manipulations. As such, this coculture model serves as a powerful tool for studying the interactions between the intestinal epithelium and its surrounding stroma, providing new insights into stem cell biology, tissue regeneration, and disease mechanisms. Here, we introduce the methods of mouse crypt isolation, intestinal organoid culture, and its coculture with mesenchymal cell.

LTβR deficiency causes lymph node aplasia and impaired B cell differentiation.

Secondary lymphoid organs (SLOs) provide the confined microenvironment required for stromal cells to interact with immune cells to initiate adaptive immune responses resulting in B cell differentiation. Here, we studied three patients from two families with functional hyposplenism, absence of tonsils, and complete lymph node aplasia, leading to recurrent bacterial and viral infections. We identified biallelic loss-of-function mutations in LTBR, encoding the lymphotoxin beta receptor (LTβR), primarily expressed on stromal cells. Patients with LTβR deficiency had hypogammaglobulinemia, diminished memory B cells, regulatory and follicular T helper cells, and dysregulated expression of several tumor necrosis factor family members. B cell differentiation in an ex vivo coculture system was intact, implying that the observed B cell defects were not intrinsic in nature and instead resulted from LTβR-dependent stromal cell interaction signaling critical for SLO formation. Collectively, we define a human inborn error of immunity caused primarily by a stromal defect affecting the development and function of SLOs.

Selective Pyk2 inhibition enhances bone restoration through SCARA5-mediated bone marrow remodeling in ovariectomized mice

Understanding the intricate cellular interactions involved in bone restoration is crucial for developing effective strategies to promote bone healing and mitigate conditions such as osteoporosis and fractures. Here, we provide compelling evidence supporting the anabolic effects of a pharmacological Pyk2 inhibitor (Pyk2-Inh) in promoting bone restoration. In vitro, Pyk2 signaling inhibition markedly enhances alkaline phosphatase (ALP) activity, a hallmark of osteoblast differentiation, through activation of canonical Wnt/β-catenin signaling. Notably, analysis of human mesenchymal stem cells through RNA-seq revealed a novel candidate, SCARA5, identified through Pyk2-Inh treatment. We demonstrate that Scara5 plays a crucial role in suppressing the differentiation from stromal cells into adipocytes, and accelerates lineage commitment to osteoblasts, establishing Scara5 as a negative regulator of bone formation. Additionally, Pyk2 inhibition significantly impedes osteoclast differentiation and bone resorption. In a co-culture system comprising osteoblasts and osteoclasts, Pyk2-Inh effectively suppressed osteoclast differentiation, accompanied by a substantial increase in the transcriptional expression of Tnfrsf11b and Csf1 in osteoblasts, highlighting a dual regulatory role in osteoblast-osteoclast crosstalk. In an ovariectomized mouse model of osteoporosis, oral administration of Pyk2-Inh significantly increased bone mass by simultaneously reducing bone resorption, promoting bone formation and decreasing bone marrow fat. These results suggest Pyk2 as a potential therapeutic target for both adipogenesis and osteogenesis in bone marrow. Our findings underscore the importance of Pyk2 signaling inhibition as a key regulator of bone remodeling, offering promising prospects for the development of novel osteoporosis therapies.

E2 signaling in myofibers promots macrophage efferocytosis in mouse skeletal muscles with cardiotoxin-induced acute injury

To investigate the effect of E2 signaling in myofibers on muscular macrophage efferocytosis in mice with cardiotoxin-induced acute skeletal muscle injury. Female wild-type C57BL/6 mice with and without ovariectomy and male C57BL/6 mice were given a CTX injection into the anterior tibial muscle to induce acute muscle injury, followed by intramuscular injection of β-estradiol (E2) or 4-hydroxytamoxifen (4-OHT). The changes in serum E2 of the mice were detected using ELISA, and the number, phenotypes, and efferocytosis of the macrophages in the inflammatory exudates and myofiber regeneration and repair were evaluated using immunofluorescence staining and flow cytometry. C2C12 cells were induced to differentiate into mature myotubes, which were treated with IFN- γ for 24 before treatment with β -Estradiol or 4-OHT. The treated myotubes were co-cultured with mouse peritoneal macrophages in a 1:2 ratio, followed by addition of PKH67-labeled apoptotic mouse mononuclear spleen cells induced by UV irradiation, and macrophage efferocytosis was observed using immunofluorescence staining and flow cytometry. Compared with the control mice, the female mice with ovariectomy showed significantly increased mononuclear macrophages in the inflammatory exudates, with increased M1 cell percentage, reduced M2 cell percentage and macrophage efferocytosis in the injured muscle, and obviously delayed myofiber regeneration and repair. In the cell co-culture systems, treatment of the myotubes with β-estradiol significantly increased the number and proportion of M2 macrophages and macrophage efferocytosis, while 4-OHT treatment resulted in the opposite changes. In injured mouse skeletal muscles, myofiber E2 signaling promotes M1 to M2 transition to increase macrophage efferocytosis, thereby relieving inflammation and promoting muscle regeneration and repair.

Endothelial cell-derived exosomes trigger a positive feedback loop in osteogenesis-angiogenesis coupling via up-regulating zinc finger and BTB domain containing 16 in bone marrow mesenchymal stem cell

The close spatial and temporal connection between osteogenesis and angiogenesis around type H vasculature is referred as “osteogenesis-angiogenesis coupling”, which is one of the basic mechanisms of osteogenesis. Endothelial cells (ECs), bone marrow mesenchymal stem cells (BMSCs), and their specific lineage constitute important cluster that participate in the regulation of osteogenesis and angiogenesis in bone microenvironment. However, the regulatory mechanism of osteogenesis-angiogenesis coupling under the condition of bone healing has not been unveiled. In this study, we demonstrated that the exosome derived from ECs (EC-exo) is an initiator of type H blood vessels formation, and EC-exo acts as a mediator in orchestrating osteogenesis-angiogenesis coupling by enhancing BMSC osteogenic differentiation and EC angiogenesis both in monolayer and stereoscopic co-culture system of primary human cells. The transcriptome array indicated that zinc finger and BTB domain containing 16 (ZBTB16) is a key gene in EC-exo-mediated osteogenesis, and ZBTB16 is indispensable in EC-exo-initiated osteogenesis-angiogenesis coupling. Mechanistically, EC-exo up-regulated the expression of ZBTB16 in BMSCs, thereby promoting osteoprogenitor phenotype transformation; the osteoprogenitors further promote ECs which constitute type H vessel (H-ECs) generation by activating HIF-1α pathway; and the H-ECs conversely promotes osteogenic differentiation of BMSCs. The crosstalk between BMSCs and ECs triggered by EC-exo constitutes a positive feedback loop that enhances osteogenesis-angiogenesis coupling. This study demonstrates that EC-exo can become an effective therapeutic tool to promote bone regeneration and repair.Graphical