This position paper reviews the various effects of combination therapy by photobiomodulation therapy (PBMT) and stem cells, on different parts of the body. The aim of this paper is to reach consensus on recommendations for the parameters of PBMT regarding its application on stem cells. A significant number of studies involving PBMT, and stem cells have been published. The advantages of this combination therapy on tissue regeneration, cell differentiation and proliferation, and healing have been reported in many studies. Due to the diverse nature of study designs used with respect to light parameters, as well as a lack of well designed, ethically approved clinical trials, clinicians may benefit from suggested guidelines for clinical application based on data obtained from previous studies. These guidelines would also help researchers in designing future studies. An in-depth review of literature on the effect of PBMT on stem cells at a molecular, cellular and tissue specific level was performed, using experts in each field of PBMT. Depending on the number of studies in each field, recommendations are presented which can suggest further studies on stem cells and PBMT. PBMT has diverse applications on stem cells. Both in-vivo and in-vitro studies represent the effectiveness of PBMT in conjunction with stem cell therapy in cell proliferation, differentiation, tissue regeneration, wound healing, angiogenesis, and treatment of different diseases. However, there is a considerable lack of clinical studies in all the reviewed fields. In each category, we attempted to recommend a PBMT protocol based on information from literature, experience, and expertise. Protocols for PBMT on stem cells were reviewed in each field of medicine, and recommendations were made for further clinical studies. Not surprising, the main wavelengths used in PBMT studies in relation to stem cells, were in the range of 630-660 nm, and 800-890 nm. However, other laser parameters are in a very wide range of difference, depending on the tissue that PBMT was applied or the aim of its application.

The bone marrow microenvironment (BMM) consists of different cellular and acellular components. These components synergize in regulating the process of hematopoiesis. Various extracellular matrix proteins are found amongst the acellular components. Secreted protein acidic and rich in cysteine (SPARC) is amongst the most abundant glycoproteins in bone. Sparc/osteonectin, cwcv, and Kazal-like domains proteoglycan 2 (SPOCK2) is a member of the SPARC family, and its role in bone metabolism and hematopoiesis has not been investigated. Using female mice deficient for SPOCK2, we assessed the role of SPOCK2 in influencing bone formation, the BMM and hematopoiesis. Using micro-computed tomography we found a significant decrease in trabecular bone volume, bone mineral density and thickness, but increased cortical mineral density in SPOCK2 knockout (KO) versus wildtype (WT) bones. C-terminal telopeptide of type I collagen, a measure of bone resorption, was significantly increased in bone marrow supernatants of SPOCK2 KO mice. In the hematopoietic compartment we found an increase in hematopoietic stem cells, but a decrease of mesenchymal stromal cells and adipocytes in the bone marrow of SPOCK2 KO mice compared to control mice. Megakaryocytes were increased in SPOCK2 KO mice. In summary, deficiency of SPOCK2 leads to several alterations in the BMM. The hematopoietic effects may be due to hematopoietic cell-intrinsic effects in SPOCK2-deficient cells or due to a SPOCK2-deficient niche or both.

Hydrogel dressings have emerged as promising tools for wound healing applications. However, the complex chemical synthesis and high cost of components, such as cytokines and stem cells, in most existing designs challenge their practical application. In this study, we adopted a modular design approach and natural materials to overcome these limitations, dividing the hydrogels into three distinct functional modules. The base module consisted of an interpenetrating polymer network of gelatin and chitosan. The drug release module incorporated liposomes loaded with quercetin, while the auxiliary module utilized a complex of protocatechuic aldehyde and trivalent iron. The presence of Schiff base crosslinking and hydrogen bond formation between the three modules enhanced the self-healing properties and mechanical strength of the hydrogel. Notably, the modular hydrogel exhibited excellent antioxidant, antibacterial, macrophage differentiation, and collagen promotion capabilities. This multifunctional hydrogel demonstrated the potential to provide safe and effective treatment, accelerate wound repair processes, and serve as a promising dressing for diabetic wound management. By utilizing natural components and a modular design strategy, this hydrogel offers a practical and cost-effective solution for improving wound healing outcomes, particularly in drug-resistant and diabetic wounds.

Our previous research established that treatment with IFN-γ and TNF-α (IT) significantly enhanced the paracrine activity of MSCs, resulting in a more effective wound healing response when applied to the wound surface with supernatant from IT-stimulated MSCs (S-IT MSCs). While S-IT MSCs hold promise for advancing wound healing therapy, challenges remain in developing an approach that enhances therapeutic efficacy and simplifies administration. This study proposed a scaffold composed of sericin, known for its skin regeneration properties, to load S-IT MSCs, designated as Se + S-IT MSCs, for the protection of bioactive factors. Additionally, whether Se + S-IT MSCs exhibit a superior effect on wound healing was investigated using a rat total skin excision model. Results indicated that Se + S-IT MSCs outperformed silk sericin loaded with MSC supernatant (Se + S-MSCs) in promoting migration, proliferation, and activation of HUVECs, HaCaTs, macrophages, and HDFs. Furthermore, Se + S-IT MSCs significantly promoted macrophage polarization toward the M2 phenotype, potentiated vascularization and re-epithelialization, and enhanced collagen deposition. These effects collectively accelerated wound healing in vivo in rats. This study highlights the potential of Se + S-IT MSCs to facilitate rapid and effective wound healing, with silk sericin scaffolds serving as efficient carriers to expedite the process.

Identifying additional immune checkpoints hindering antitumor T cell responses is key to the development of next-generation cancer immunotherapies. Here, we report the induction of serotonin transporter (SERT), a regulator of serotonin levels and physiological functions in the brain and peripheral tissues, in tumor-infiltrating CD8 T cells. Inhibition of SERT using selective serotonin reuptake inhibitors (SSRIs), the most widely prescribed antidepressants, significantly suppressed tumor growth and enhanced T cell antitumor immunity in various mouse syngeneic and human xenograft tumor models. Importantly, SSRI treatment exhibited significant therapeutic synergy with programmed cell death protein 1 (PD-1) blockade, and clinical data correlation studies negatively associated intratumoral SERT expression with patient survival in a range of cancers. Mechanistically, SERT functions as a negative-feedback regulator inhibiting CD8 T cell reactivities by depleting intratumoral T cell-autocrine serotonin. These findings highlight the significance of the intratumoral serotonin axis and identify SERT as an immune checkpoint, positioning SSRIs as promising candidates for cancer immunotherapy.

Glioblastoma (GBM) is the most aggressive primary intracranial tumor, with glioblastoma stem cells (GSCs) enforcing the intratumoral hierarchy. The inflammatory microenvironment influences tumor development at varying stages, while the underlying mechanism of GSCs facing pro-inflammatory stress remains unclear. Here, we show that, in human GBM, pro-inflammatory stress from pro-inflammatory macrophages (pTAMs) maintains GSC proliferation and self-renewal. Tumor necrosis factor alpha-induced protein 6 (TNFAIP6), as a responder in patient-derived GSCs to pro-inflammatory stress tumor necrosis factor alpha (TNF-α) from human pTAMs, promotes tumor growth through binding epidermal growth factor (EGF) and prolonging EGF receptor (EGFR)-phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT) signaling activation. Meanwhile, pro-inflammatory stress-induced patient-derived GSCs secrete TNFAIP6 to transform macrophage phenotype from pTAMs to inflammatory-suppressive macrophages (sTAMs). Collectively, pharmacological or genetic disruption of TNFAIP6 autocrine and paracrine communication between patient-derived GSCs and TAMs inhibited GSC proliferation and self-renewal in vitro and in patient-derived xenograft tumor-bearing mice, suggesting that TNFAIP6 is an effective target for GBM therapy.

Hepatocytes can reprogram into biliary epithelial cells (BECs) during liver injury, but the underlying epigenetic mechanisms remain poorly understood. Here, we define the chromatin dynamics of this process using single-cell ATAC-seq and identify YAP/TEAD activation as a key driver of chromatin remodeling. An in vivo CRISPR screen highlights the histone acetyltransferase HBO1 as a critical barrier to reprogramming. HBO1 is recruited by YAP to target loci, where it promotes histone H3 lysine 14 acetylation (H3K14ac) and engages the chromatin reader zinc-finger MYND-type containing 8 (ZMYND8) to suppress YAP/TEAD-driven transcription. Loss of HBO1 accelerates chromatin remodeling, enhances YAP binding, and enables a more complete hepatocyte-to-BEC transition. Our findings position HBO1 as an epigenetic brake that restrains YAP-mediated reprogramming, suggesting that targeting HBO1 may enhance hepatocyte plasticity for liver regeneration.

Inhalation of nitrogen dioxide (NO2), a representative irritant gas, can trigger acute lung injury (ALI), typically characterized by increased permeability and dysfunction of the blood-air barrier. However, the exact mechanisms underlying NO2 inhalation-induced ALI (NO2-ALI) remain poorly understood. Using single-cell RNA sequencing (scRNA-seq), we identified significant alterations in endothelial and epithelial cells during NO2-ALI. Notably, leucine-rich alpha-2-glycoprotein 1 (Lrg1) and uncoupling protein 2 (Ucp2), which have been implicated in ALI progression, were significantly upregulated in endothelial cells following NO2 exposure (P < 0.05 compared to control). General capillaries (GCs) potentially function as stem cells, facilitating endothelial cell repair and recruiting neutrophils to amplify inflammatory responses. Furthermore, a novel subpopulation of epithelial cells, identified as lymphocyte antigen 6 A+ (Ly6a) alveolar cells, showed a significant increase in abundance (P < 0.05 compared to control) and played a pivotal role in alveolar epithelial cell differentiation after NO2 inhalation. Overall, these findings shed insights into the pathogenic roles of endothelial and epithelial cells in NO2-ALI.

Tyrosine kinase inhibitors (TKIs) are commonly used in cancer treatment, but their off-target effects can lead to serious cardiotoxicity. Our previous studies have revealed that upregulation of phosphoinositide 3-kinase (PI3K) confers considerable protection against calcium (Ca2+) disorders and cardiac dysfunction induced by sunitinib. However, the involvement of PI3K inhibition in the prevention of cardiomyocyte contraction induced by other TKIs remains unclear.

Neurodegenerative disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), Amyotrophic Lateral Sclerosis (ALS), Multiple Sclerosis (MS) and Frontotemporal Dementia (FTD) share key pathological features, including neuroinflammation, oxidative stress, mitochondrial dysfunction, autophagic dysfunction, and DNA damage. By identifying cytosolic DNA and triggering the type I interferon response, the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway regulates neuroinflammation. Dysregulated cGAS-STING signaling has been linked to neuroinflammation and neuronal degeneration across multiple neurodegenerative conditions. In many neurodegenerative disorders, neuroinflammation is mediated by the cGAS-STING pathway. Mitochondrial malfunction and impaired autophagy cause cytosolic DNA buildup in Huntington's, Parkinson's, and Alzheimer's diseases, which activates cGAS-STING and drives chronic inflammation. This pathway is triggered by TDP-43 pathology and nucleic acid dysregulation in ALS and FTD, which leads to neuronal destruction. Both central demyelination and peripheral immunological responses are linked to cGAS-STING activation in multiple sclerosis. Various inhibitors, such as RU.521, H-151, and naturally occurring compounds like metformin, potentially attenuate cGAS-STING-mediated neuroinflammation and associated pathologies. H-151 significantly decreased the expression of pro-inflammatory markers in murine macrophage J774 cells activated with cGAMP: TNF-α by 68 %, IFN-β by 84 %, and CXCL10 by 96 %. cGAS-STING inhibitors target neuroinflammation, offering a disease-modifying approach unlike current symptomatic treatments. However, challenges like blood-brain barrier penetration, off-target effects, and immune suppression hinder clinical translation, necessitating optimized drug delivery and immune modulation. With a focus on its potential for future clinical applications, this review explores the role of the cGAS-STING pathway in neurodegeneration and new treatment approaches.

Cordycepin, also known as 3'-deoxyadenosine, is a bioactive natural antibiotic with numerous pharmacological properties including anticancer activity. Unfortunately, cordycepin is rapidly deaminated by adenosine deaminase (ADA) in vivo, which leads to the inactivation of this potent natural compound. In the present study, an ADA-resistant cordycepin prodrug (2) with the 6-NH2 masked by a glutamate-based protecting group was developed. Additionally, this cordycepin prodrug exhibited stability in serum-containing media. The prodrug is non-toxic in its standalone form, and the release of cordycepin occurs in the presence of Pseudomonas carboxypeptidase G2 (CPG2), rendering it appropriate for directed enzyme prodrug therapy. The concurrent application of CPG2 and prodrug significantly reduced the proliferation of 4T1 and U251 cancer cells, promoted apoptosis, and impeded the colony formation of 4T1 cells. Subsequent assessments utilizing the patient-derived breast cancer organoid model have demonstrated notable anticancer efficacy. The development of this prodrug presents a promising strategy to mitigate the inactivation of cordycepin in cancer therapy and minimizing toxicity to healthy cells.

RP33 is a form of autosomal dominant retinitis pigmentosa (adRP), which is caused by heterozygous variants in the SNRNP200 gene. Peripheral blood mononuclear cells (PBMCs) were isolated from a 31-year-old Chinese patient with a heterozygous c.2359G > A variant in the SNRNP200 gene. PBMCs were reprogrammed into an induced pluripotent stem cell (iPSC) line BIOi004-A. The established iPSC line had normal karyotype, expressed undifferentiated stem cell markers, and was capable to differentiate into the three germ layers in vivo.

The autoimmune response driving hematopoietic stem and progenitor cell (HSPC) destruction in immune-mediated aplastic anemia (AA) remains incompletely understood. We previously identified a disease-specific immune cell network involving T-, B-, and myeloid cells. However, the interactions within this network, the interaction with the microenvironment and the chronological events in AA development, remain unclear. In this study, we aimed to characterize the changes occurring during disease development and to define the interactions between potential autoreactive cells and their target. Using imaging mass cytometry, we analyzed bone marrow (BM) biopsies from AA patients at diagnosis and after treatment with horse-derived anti-thymocyte globulin (hATG), and six controls. Within the hypocellular BM architecture, we identified lymphoid-dominant 'immune hotspots' with high densities of pro-inflammatory lymphocytes, and macrophage-enriched hotspots that additionally contained activated macrophages in proximity to progenitors. These immune hotspots potentially represent sites where the active immune response resulting in HSPC destruction takes place. In BM regions depleted of progenitors, effector cells with a differentiated phenotype remain. Our data indicate that HSPC destruction in AA is mediated by coordinated interactions among specific immune cell subpopulations. As the immune response progresses and HSPCs are depleted, the immune composition shifts, with activated T- and B-cells differentiating into terminally differentiated T-cells and plasma cells. In patients with normalizing BM post-hATG treatment, most immune hotspots were depleted, underscoring their potential pathogenic role. Collectively, our study visualizes the complex interactions among immune cell subpopulations and, for the first time, reveals the order of events in the immune-mediated pathogenesis of AA.

Spinal cord injury (SCI) is a central nervous system (CNS) disease with a high disability rate, and reconstructing motor function after SCI remains a global challenge. Recent advancements in rehabilitation and regenerative medicine offer new approaches to SCI repair. Electrical stimulation has been shown to alter cell membrane charge distribution, generating action potentials, and affecting cell behavior. This method aids axon regeneration and neurotrophic factor upregulation, crucial for nerve repair. Biomaterials, used as scaffolds or coatings in cell culture and tissue engineering, enhance cell proliferation, migration, differentiation, and tissue regeneration. Electroactive biomaterials combined with electrical stimulation show promise in regenerating nerve, heart, and bone tissues. In this paper, different types of electrical stimulation and biomaterials applied to SCI are described, and the current application and research progress of electrical stimulation combined with biomaterials in the treatment of SCI are described, as well as the future prospects and challenges.

Heart failure is the final outcome of most cardiovascular diseases and shares risk factors with other cardiovascular pathologies. Among these, inflammation plays a central role in disease progression and myocardial remodeling. Over the past 2 decades, numerous studies have explored immune-related mechanisms in cardiovascular disease, highlighting the importance of immune cross-talk between the heart and extra-cardiac organs, including bone marrow, spleen, liver, gut, and adipose tissue. This review examines how immune interactions among these organs contribute to heart failure pathogenesis, with a focus on clonal hematopoiesis, an age-related alteration of hematopoietic stem cells that fosters pathological bone marrow-heart communication. Additionally, we explore recent advances in the understanding of clonal hematopoiesis and its role in heart failure, emphasizing its implications for prognosis and potential therapeutic interventions. By integrating insights from immunology, metabolism, and aging, we provide a comprehensive perspective on the immunologic determinants of heart failure, paving the way for precision medicine approaches aimed at mitigating cardiovascular risk.

Liver fibrosis (LF) results from various causes, which require finding conserved mechanisms to help treat related diseases. Although adipose-derived stem cells (ADSCs) transplantation can alleviate hepatic fibrosis, their mechanism remains unclear. Accordingly, we explored the efficacy and mechanisms behind ADSCs transplantation in two LF models.

Repair of the tendon-bone interface (TBI) remains a significant clinical challenge due to its complex biomechanical environment and hierarchical structure. Conventional surgical approaches often fail to fully reestablish native tissue architecture and function. In recent years, tissue engineering strategies have increasingly emphasized the application of mesenchymal stem cells (MSCs) and platelet-derived products to promote regeneration. MSCs possess multilineage differentiation potential and immunomodulatory capabilities, making them attractive candidates for TBI repair. Platelets, through their rich secretome, orchestrate essential regenerative processes such as cell recruitment, angiogenesis, and immune modulation. This review explores the molecular crosstalk between MSCs and platelets, critically examines current approaches utilizing platelet-rich plasma (PRP)-MSC combinations and platelet-derived exosome therapies and underscores the urgent need for standardization to optimize therapeutic outcomes in PRP-MSC-based regenerative strategies.

Here, we present a protocol to generate key pancreatic cell types in vitro using human pluripotent stem cell (hPSC)-based Matrigel-overlay organoid differentiation. These include multipotent and bipotent progenitors, endocrine progenitors, and hormone-producing endocrine cells. We describe steps for culturing hPSCs as a 2D monolayer, applying a Matrigel overlay to create a 3D epithelial niche, and guiding stepwise differentiation. This system supports live-cell imaging and real-time tracking of morphogenesis and fate decisions, providing a platform for studying organ development and disease. For complete details on the use and execution of this protocol, please refer to Ulf et al.1.

Extraembryonic endoderm stem cells (XENs) resemble the primitive endoderm of blastocyst and provide valuable alternatives for understanding hypoblast development and building stem cell-based embryo models. Here, we report that a chemical cocktail (FGF4, BMP4, IL-6, XAV939, and A83-01) enables the de novo derivation and long-term culture of bovine XENs (bXENs) from blastocysts. Transcriptomic and epigenomic analyses confirm the identity of bXENs and reveal that bXENs resemble the hypoblast lineages of early bovine peri-implantation embryos. Furthermore, we show that bXENs maintain the stemness of expanded embryonic stem cells (EPSCs) and prevent them from undergoing differentiation. The chemical cocktail sustaining bXENs also facilitates the growth of epiblasts in developing pre-implantation embryos. Finally, 3D assembly of bXENs with bovine EPSCs and trophoblast stem cells enables efficient generation of blastoids that resemble blastocysts. bXENs and blastoids established here represent accessible in vitro models for understanding embryogenesis and improving reproductive efficiency in domestic livestock.

Auricular avulsion injuries present complex reconstructive challenges due to the intricate three-dimensional (3D) structure and vascular supply of the ear. This review examines traditional and emerging techniques in auricular trauma repair, including microsurgical advancements, digital planning, tissue engineering, and 3D bioprinting, highlighting their impact on reconstructive outcomes.