MSCs alleviate LPS-induced acute lung injury by inhibiting the proinflammatory function of macrophages in mouse lung organoid-macrophage model

Enhance the therapeutic efficacy of human umbilical cord-derived mesenchymal stem cells in prevention of acute graft-versus-host disease through CRISPLD2 modulation

BACKGROUND

Acute graft-versus-host disease (aGVHD) remains a major life-threatening complication of allogeneic haematopoietic cell transplantation (allo-HSCT), often limiting the therapeutic efficacy of allo-HSCT. Recent studies have suggested that mesenchymal stem cells (MSCs) may be beneficial for the treatment of aGVHD. However, the therapeutic potential of MSCs is often negatively impacted by their heterogeneity.

METHODS

To investigate MSCs heterogeneity, we conducted single-cell transcriptomic analysis of human umbilical cord-derived MSCs (HUC-MSCs) and identified key feature genes that distinguish MSCs subpopulations. The function of the newly discovered biomarker CRISPLD2 was also explored. We engineered human umbilical cord-derived MSCs (HUC-MSCs) to overexpress the CRISPLD2 gene using lentiviral vectors. The downstream regulatory effects of CRISPLD2 overexpression were assessed through bulk RNA sequencing. Additionally, we evaluated its impact on cellular senescence using Western blotting and β-galactosidase (SA-β-gal) staining. The immunoregulatory capability of HUC-MSCs was tested through coculture experiments with T cells and liver organoids in vitro. Mitochondrial function was analysed via flow cytometry and electron microscopy. The in vivo therapeutic effects of HUC-MSCs on aGVHD were evaluated using an aGVHD murine model. The graft-versus-leukaemia (GVL) effect was measured via the inoculation of luciferase-positive A20 cells, and tumour growth was monitored via bioluminescence imaging.

RESULTS

Our findings indicated that the CRISPLD2 gene is heterogeneously expressed in HUC-MSCs subsets characterized by stemness and immunosuppressive properties. Transcriptomic analysis revealed that CRISPLD2 overexpression suppressed calcium ion binding and G protein-coupled receptor signalling. In vitro studies demonstrated a marked increase in IL-10 secretion, which enhanced T-cell suppression in CRISPLD2-modified HUC-MSCs. The in vivo results demonstrated that transfusion of CRISPLD2-overexpressing HUC-MSCs ameliorated aGVHD while maintaining GVL activity. Mechanistically, CRISPLD2 overexpression overcomes the mitochondrial damage mediated by extracellular ATP and LPS in HUC-MSCs by inhibiting P2Y11 receptor signalling, thereby preserving their stemness and IL-10-mediated immunosuppressive functions.

CONCLUSIONS

Our study revealed that CRISPLD2 is a novel marker for identifying HUC-MSCs subpopulation with enhanced immunosuppressive functions. CRISPLD2 overexpression enhances the immunosuppressive function of HUC-MSCs by inhibiting P2Y11 receptor signalling. Targeting CRISPLD2 is a promising strategy to improve the therapeutic efficacy of HUC-MSCs in aGVHD while maintaining GVL activity.

Baicalin inhibits LPS-induced apoptosis and inflammation in WI- 38 cells by promoting FOXA2/TRIM27 Interaction: Implications for pediatric pneumonia mechanisms

BACKGROUND

Pediatric pneumonia is lung inflammation in newborns caused by many factors, which can impair the respiratory, circulatory and nervous systems and affect their growth and development. Baicalin, a flavonoid separated from Scutellaria baicalensis Georgi, possesses anti-inflammatory effects in lung diseases. The aim of this study was to explore the molecular mechanism of baicalin in exerting a protective effect in neonatal pneumonia.

METHODS

Effect of baicalin on viability of human fibroblast cells (WI-38 cell) was detected by CCK-8 assay. Then, the WI-38 cells were treated with lipopolysaccharide (LPS). Cell apoptosis and inflammatory cytokines were assessed by flow cytometry and ELISA. Additionally, the oxidative stress and endoplasmic reticulum stress (ERS) were evaluated using specific assays. The mRNA and protein levels were assessed by qRT-PCR and western blot. Finally, the binding between FOXA2 and TRIM27 was predicted and verified by employing the Jaspar database, ChIP and dual luciferase reporter assays.

RESULTS

1-40 µM baicalin had no impact on the viability in WI-38 cells, and 40 µM baicalin increased the viability of LPS-inhibited cells. Besides, baicalin mitigated the effects of LPS on apoptosis, inflammation, oxidative stress and ERS in WI-38 cells. Moreover, TRIM27 exhibited low expression levels in pediatric pneumonia and LPS-induced cells. Furthermore, baicalin promoted TRIM27 expression and inhibited the effects of LPS induction on cell production. Mechanically, FOXA2 was positively correlated with TRIM27 expression and baicalin inhibited the adverse effects of LPS induction on WI-38 cells via FOXA2/TRIM27.

CONCLUSION

These findings suggested that baicalin miaght exert protective effects against pediatric pneumonia by modulating FOXA2/TRIM27-dependent pathways.

Organoids in disease modeling and regenerative medicine

Organoid technology has the potential to revolutionize biomedical research by providing more physiologically relevant models for studying human development, disease mechanisms, and therapeutic development. Derived from stem cells, organoids self-organize into three-dimensional tissues that replicate the structures and functions of their in vivo counterparts. Their ability to mimic organ-specific microstructures offers new tools for investigating organogenesis, modeling genetic disorders, and screening potential therapeutics using human cells. Additionally, organoids hold promise for regenerative medicine as potential transplantable tissues for repairing or replacing damaged organs. However, challenges such as batch variability, standardization, vascularization, long-term viability, and lack of immune cells remain, hindering their clinical translation and use in disease studies. Recent efforts have focused on improving reproducibility, incorporating bioengineering techniques for enhanced maturation, and optimizing differentiation methods. This collection highlights recent advances in the respiratory, renal, and retinal organoid systems. From refining cryopreservation methods to using organoid models for virus neutralization and inflammatory studies, these contributions emphasize the potential of organoids in translational research and regenerative medicine.

The impact of the inflammatory pulmonary microenvironment on the behavior and function of mesenchymal stromal cells

INTRODUCTION

Acute respiratory distress syndrome is characterized by the dysregulation and activation of several inflammatory pathways which lead to widespread inflammation in the lungs. Presently, direct therapy is unavailable and the use of mesenchymal stromal cells as a direct therapy has been proposed, as early-phase studies have shown promise.

AREAS COVERED

MSCs exert various therapeutic effects on the inflammatory microenvironment, such as anti-microbial effects, restoration of the alveolar-capillary barrier, and exuding various anti-inflammatory effects. However, to exert these effects MSCs need to be submitted to specific external stimuli which can affect their immunomodulation, survival, migration and metabolic state. This review references several articles found through targeted searches in PubMed [Accessed between November 2024 and March 2025], for key terms such as 'mesenchymal stromal cells', 'inflammatory microenvironment', anti-inflammatory', 'metabolism', and 'immunomodulation'.

EXPERT OPINION

The advancement of MSCs therapy in the treatment of ARDS has not progressed as effectively as one might have anticipated. Several clinical findings have established patient subgroups based on inflammatory cytokine profiles and severity of ARDS. This variation in patients may influence the clinical efficacy of MSCs and instead of concluding that MSCs therapy is not worth pursuing, more research is needed to develop an appropriate therapy.

Coculture of mesenchymal stem cells and macrophage: A narrative review

Stem cell transplantation is a promising treatment for repairing damaged tissues, but challenges like immune rejection and ethical concerns remain. Mesenchymal stem cells (MSCs) offer high differentiation potential and immune regulatory activity, showing promise in treating diseases such as gynecological, neurological, and kidney disorders. With scientific progress, MSC applications are overcoming traditional treatment limitations. In MSCs-macrophage coculture, MSCs transform macrophages into anti-inflammatory M2 macrophages, reducing inflammation, whereas macrophages enhance MSCs osteogenic differentiation. This coculture is vital for immune modulation and tissue repair, with models varying by contact type and dimensional arrangements. Factors such as coculture techniques and cell ratios influence outcomes. Benefits include improved heart function, wound healing, reduced lung inflammation, and accelerated bone repair. Challenges include optimizing coculture conditions. This study reviews the methodologies, factors, and mechanisms of MSC-macrophage coculture, providing a foundation for tissue engineering applications. SIGNIFICANCE STATEMENT: This review underlines the significant role of mesenchymal stem cell-macrophage coculture, providing a foundation for tissue engineering application.

Enhancing Lung Recovery: Inhaled Poly(lactic-co-glycolic) Acid Encapsulating FTY720 and Nobiletin for Lipopolysaccharide-Induced Lung Injury, with Advanced Inhalation Tower Technology

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), a rapidly progressing respiratory failure condition, results in a high mortality rate, especially in severe cases. Numerous trials have investigated various pharmacotherapy approaches, but their effectiveness remains uncertain. Here, we present an inhaled nanoformulation of fingolimod (FTY720)-nobiletin (NOB)- poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) with good biocompatibility and a sustained-release pharmacological effect. The formulation decreases the toxicity of FTY720 and increases the bioavailability of NOB since we use PLGA with a high biocompatibility to encapsulate FTY720 and NOB at the same time. In vitro, in comparison to treatment with the pure drug, we demonstrated that FTY720-NOB-PLGA NPs can reduce interleukin-6 (IL-6) and reactive oxygen species (ROS) release by macrophages after lipopolysaccharide (LPS) stimulation more efficiently. In vivo, we used an inhalation tower system that allowed the exposure of unanesthetized mice to aerosolized FTY720-NOB-PLGA NPs under controlled conditions. We demonstrated that inhaled FTY720-NOB-PLGA NPs can attenuate lung injury after LPS exposure by suppressing cytokine release, such as IL-6 and tumor necrosis factor-α (TNF-α). The trigger pathway of ALI, including nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and p38 mitogen-activated protein kinase, was also efficiently inhibited. Furthermore, the inhalation treatment provided a good safety profile, without detrimental effects on biochemical markers and lung function. We provided the feasibility of administering inhalation of NPs noninvasively with continuous monitoring of lung function. The aerosolized FTY720-NOB-PLGA NPs we developed show excellent promise for acute lung injury therapy in the future.

Chinese Medicine Combined with Adipose Tissue-Derived Mesenchymal Stem Cells: A New Promising Aspect of Integrative Medicine

Adipose tissue-derived mesenchymal stem cells (ADSCs) are crucially involved in various biological processes because of their self-renewal, multi-differentiation, and immunomodulatory activities. Some ADSC's characteristics have been associated with the basic theory of Chinese medicine (CM), especially the Meridian theory. CM can improve the biological properties of ADSCs to facilitate their use in injury treatment, restore immune homeostasis, and inhibit inflammatory responses. Therefore, the combination of CM and ADSCs may be a new promising research direction in integrative medicine of China. This review summarizes the association between CM and ADSCs to assess the potential application value of their combination against various diseases.

Enhanced itaconic acid secretion from macrophages mediates the protection of mesenchymal stem cell-derived exosomes on lipopolysaccharide-induced acute lung injury mice

BACKGROUND

Alveolar macrophages (AMs) is critical to exacerbate acute lung injury (ALI) induced by lipopolysaccharide (LPS) via inhibiting inflammation, which could by shifted by mesenchymal stem cell-derived exosomes (MSC-exos). But the underlying rationale is not fully clarified. Our study aimed to analyze the significance of itaconic acid (ITA) in mediating the protective effects of MSC-exos on LPS-induced ALI.

METHODS

MSC-exos were used to treat pulmonary microvascular endothelial cells (PMVECs) co-cultured with AMs under LPS stimulation. si-IRG1 was transfected to AMs. PMVEC permeability, apoptosis rates, and inflammatory cytokine levels were assessed. In vivo, C57BL/6 wild-type (WT) and Irg1-/- mice were employed to explore the protection of MSC-exos against LPS-induced ALI. The lung injury was determined by histological and biochemical assays. ITA levels were measured using gas chromatography-mass spectrometry. Western blot and flow cytometry analyses were performed to assess M1/M2 polarization.

RESULTS

Co-culture with AMs significantly increased PMVEC permeability, apoptosis rates, IL-6, TNF-α levels and Claudin-5 and ZO-1 expression induced by LPS treatment, which were attenuated by MSC-exos accompanied by enhanced ITA level. After si-IRG1 transfection, MSC-exos' protective efficacy was reversed, with suppressed M2 polarization. In vivo, MSC-exos alleviated alveolar structure disruption, pulmonary edema, inflammation and increased ITA concentration in WT mice but had reduced effects in Irg1-/- mice, with neglected M2 polarization.

CONCLUSIONS

ITA secretion facilitated the MSC-exos' protective benefits on LPS-induced PMVEC damage and ALI in mice by promoting AM M2 polarization, highlighting a potential therapeutic strategy for ALI and related inflammatory lung diseases.

Application of lipopolysaccharide in establishing inflammatory models

Lipopolysaccharide (LPS), a unique component of the outer membrane of Gram-negative bacteria, possesses immune-activating properties. It induces an immune response by stimulating host cells to produce a lot of inflammatory cytokines with a thermogenic effect, which may cause an inflammatory response. In the past few decades, the structure and function of LPS and its mechanism leading to inflammation have been extensively analyzed. Since LPS can cause inflammation, it is often used to establish inflammation models. These models are crucial in the study of inflammatory diseases that pose a serious threat to human health. In addition, the non-pro-inflammatory effects of LPS under certain circumstances are also being studied widely. This review summarizes the methods by which LPS has been used to establish inflammatory models at the cellular and animal levels to study related diseases. It also introduces in detail the evaluation indicators necessary for the successful establishment of these models, providing a reference for future research.

Organoids: development and applications in disease models, drug discovery, precision medicine, and regenerative medicine

Organoids are miniature, highly accurate representations of organs that capture the structure and unique functions of specific organs. Although the field of organoids has experienced exponential growth, driven by advances in artificial intelligence, gene editing, and bioinstrumentation, a comprehensive and accurate overview of organoid applications remains necessary. This review offers a detailed exploration of the historical origins and characteristics of various organoid types, their applications-including disease modeling, drug toxicity and efficacy assessments, precision medicine, and regenerative medicine-as well as the current challenges and future directions of organoid research. Organoids have proven instrumental in elucidating genetic cell fate in hereditary diseases, infectious diseases, metabolic disorders, and malignancies, as well as in the study of processes such as embryonic development, molecular mechanisms, and host-microbe interactions. Furthermore, the integration of organoid technology with artificial intelligence and microfluidics has significantly advanced large-scale, rapid, and cost-effective drug toxicity and efficacy assessments, thereby propelling progress in precision medicine. Finally, with the advent of high-performance materials, three-dimensional printing technology, and gene editing, organoids are also gaining prominence in the field of regenerative medicine. Our insights and predictions aim to provide valuable guidance to current researchers and to support the continued advancement of this rapidly developing field.

Spatial transcriptomic sequencing reveals immune microenvironment features of Mycobacterium tuberculosis granulomas in lung and omentum

Granulomas are a key pathological feature of tuberculosis (TB), characterized by cell heterogeneity, spatial composition, and cellular interactions, which play crucial roles in granuloma progression and host prognosis. This study aims to analyze the transcriptome profiles of cell populations based on their spatial location and to understand the core transcriptome characteristics of granuloma formation and development. Methods In this study, we collected four clinical biopsy samples including Mycobacterium tuberculosis (Mtb) infected lung (MTB-L) and omentum tissues (MTB-O), as well as two lung and omentum biopsies from non-TB patients. The tissues were analyzed by spatial transcriptomics to create a spatial atlas. Utilizing cell enrichment scores and intercellular communication analysis, we investigated the transcriptome signatures of cell populations in various spatial regions and identified genes that may play a decisive role in the formation of pulmonary and omental tuberculosis granulomas. To validate our major findings, an in vitro TB model based on organoid-macrophage co-culture was established. Results Spatial transcriptomics mapped the cell composition and spatial distribution characteristics of tuberculosis granulomas in lung and omental tissues infected with Mtb. The characteristics and evolutionary relationships of major cell populations in granulomas reveal a shift in the immune microenvironment: from a predominance of B cells and fibroblasts in pulmonary granulomas to a predominance of myeloid cells and fibroblasts in omental granulomas. Furthermore, our data identified key differentially expressed genes across cell clusters and regions, showing that upregulation of collagen genes is a common feature of granulomas. Using an organoid-macrophage co-culture model, we demonstrated the notable efficacy of Thrombospondin-1 (THBS1) in reducing protein expression levels related to extracellular matrix remodeling. Conclusion These results provide insights into the pathogenesis and development of tuberculosis, enhancing our understanding of the composition and interactions of tuberculosis granuloma cells from a spatial perspective, and pave the way for novel adjuvant treatments for tuberculosis.

In vitro co-culture models for studying organoids-macrophages interaction: the golden technology of cancer immunotherapy

Macrophages, as the largest immune cell group in tumour tissues, play a crucial role in influencing various malignant behaviours of tumour cells and tumour immune evasion. As the research on macrophages and cancer immunotherapy develops, the importance of appropriate research models becomes increasingly evident. The development of organoids has bridged the gap between traditional two-dimensional (2D) cultures and animal experiments. Recent studies have demonstrated that organoids exhibit similar physiological characteristics to the source tissue and closely resemble the in vivo genome and molecular markers of the source tissue or organ. However, organoids still lack an immune component. Developing a co-culture model of organoids and macrophages is crucial for studying the interaction and mechanisms between tumour cells and macrophages. This paper presents an overview of the establishment of co-culture models, the current research status of organoid macrophage interactions, and the current status of immunotherapy. In addition, the application prospects and shortcomings of the model are explained. Ultimately, it is hoped that the co-culture model will offer a preclinical testing platform for maximising a precise cancer immunotherapy strategy.

STING-deficiency in lung resident mesenchymal stromal cells contributes to the alleviation of LPS-induced lung injury

Acute respiratory distress syndrome (ARDS) is characterized by acute diffuse inflammatory lung injury with a high mortality rate. Mesenchymal stromal cells (MSC) are pluripotent adult cells that can be extracted from a variety of tissues, including the lung. Lung-resident MSC (LR-MSC) located around vascular vessels and act as important regulators of lung homeostasis, regulating the balance between lung injury and repair processes. LR-MSC support the integrity of lung tissue by modulating immune responses and releasing trophic factors. Studies have reported that the STING pathway is involved in the progression of lung injury inflammation, but the specific mechanism is unclear. In this study, we found that STING deficiency could ameliorate lipopolysaccharides (LPS)-induced acute lung injury, STING knockout (STING KO) LR-MSC had an enhanced treatment effect on acute lung injury. STING depletion protected LR-MSC from LPS-induced apoptosis. RNA-sequencing and Western blot results showed that STING KO LR-MSC expressed higher levels of MSC immunoregulatory molecules, such as Igfbp4, Icam1, Hgf and Cox2, than WT LR-MSC. This study highlights that LR-MSC have a therapeutic role in acute lung injury, and we demonstrate that STING deficiency can enhance the immunomodulatory function of LR-MSC in controlling lung inflammation. Thus, STING can be used as an intervention target to enhance the therapeutic effect of MSC.