Dynamic evolution of bone marrow adipocyte in B cell acute lymphoblastic leukemia: insights from diagnosis to post-chemotherapy

Adipocyte is a unique and versatile component of bone marrow microenvironment (BMM). However, the dynamic evolution of Bone Marrow (BM) adipocytes from the diagnosis of B cell Acute Lymphoblastic Leukemia (B-ALL) to the post-treatment state, and how they affect the progression of leukemia, remains inadequately explicated. Primary patient-derived xenograft models (PDXs) and stromal cell co-culture system are employed in this study. We show that the dynamic evolution of BM adipocytes from initial diagnosis of B-ALL to the post-chemotherapy phase, transitioning from cellular depletion in the initial leukemia niche to a fully restored state upon remission. Increased BM adipocytes retards engraftment of B-ALL cells in PDX models and inhibits cells growth of B-ALL in vitro. Mechanistically, the proliferation arrest of B-ALL cells in the context of adipocytes-enrichment niche, might attribute to the presence of adiponectin secreted by adipocytes themselves and the absence of cytokines secreted by mesenchymal stem cell (MSCs). In summary, our findings offer a novel perspective for further in-depth understanding of the dynamic balance between BMM and B-ALL.

Dysregulation of CD4+ and CD8+ resident memory T, myeloid, and stromal cells in steroid-experienced, checkpoint inhibitor colitis

BACKGROUND

Colitis caused by checkpoint inhibitors (CPI) is frequent and is treated with empiric steroids, but CPI colitis mechanisms in steroid-experienced or refractory disease are unclear.

METHODS

Using colon biopsies and blood from predominantly steroid-experienced CPI colitis patients, we performed multiplexed single-cell transcriptomics and proteomics to nominate contributing populations.

RESULTS

CPI colitis biopsies showed enrichment of CD4+resident memory (RM) T cells in addition to CD8+ RM and cytotoxic CD8+ T cells. Matching T cell receptor (TCR) clonotypes suggested that both RMs are progenitors that yield cytotoxic effectors. Activated, CD38+ HLA-DR+ CD4+ RM and cytotoxic CD8+ T cells were enriched in steroid-experienced and a validation data set of steroid-naïve CPI colitis, underscoring their pathogenic potential across steroid exposure. Distinct from ulcerative colitis, CPI colitis exhibited perturbed stromal metabolism (NAD+, tryptophan) impacting epithelial survival and inflammation. Endothelial cells in CPI colitis after anti-TNF and anti-cytotoxic T-lymphocyte-associated antigen 4 (anti-CTLA-4) upregulated the integrin α4β7 ligand molecular vascular addressin cell adhesion molecule 1 (MAdCAM-1), which may preferentially respond to vedolizumab (anti-α4β7).

CONCLUSIONS

These findings nominate CD4+ RM and MAdCAM-1+ endothelial cells for targeting in specific subsets of CPI colitis patients.

Placenta-Derived Decidua Stromal Cells: A New Frontier in the Therapy of Acute Graft-Versus-Host Disease

Acute graft-versus-host disease (GVHD) is a frequent and potentially life-threatening complication following allogeneic hematopoietic cell transplantation (HCT). Mesenchymal stromal cells (MSCs), rare precursors found in all body tissues, possess immunosuppressive properties and can inhibit alloreactivity both in vitro and in vivo. Two decades ago, we introduced bone marrow-derived (BM) MSCs as a novel therapy for acute GVHD. While some patients responded to BM-MSCs, the response was not universal. Commercially available BM-MSCs are now used for acute GVHD treatment in Canada, Japan, and New Zealand. The fetus is protected from the mother's immune system by the placenta, and our research found that placenta-derived decidua stromal cells (DSCs) offer a stronger immunosuppressive effect than other sources of stromal cells. Safety studies in rabbits, rats, mice, and humans have shown negligible or no side effects from BM-MSCs or DSCs. In a phase I/II trial for severe acute GVHD, we treated 21 patients (median age, 49 years; range 1.6-72 years) with severe biopsy-proven gastrointestinal acute GVHD. The median cell dose of DSCs was 1.2 × 106 (range 0.9-2.9) cells/kg body weight, with a median of 2 (range 1-6) infusions given 1 week apart. The cell viability of DSCs was 93% (range, 69%-100%), and the median cell passage number was 4 (range, 2-4). All patients responded, with a complete response of acute GVHD in 11 patients and partial response in 10 and 1-year survival of 81%. Randomized trials are needed to prove the superiority of DSCs compared to ruxolitinib and/or other novel immunosuppressive therapies.

Umbilical cord mesenchymal stem cell-derived exosomes inhibits fibrosis in human endometrial stromal cells via miR-140-3p/FOXP1/Smad axis

Endometrial fibrosis is the histologic appearance of intrauterine adhesion (IUA). Emerging evidences demonstrated umbilical cord mesenchymal stem cell-derived exosomes (UCMSC-exo) could alleviate endometrial fibrosis. But the specific mechanism is not clear. In this study, we explored the effect of UCMSC-exo on endometrial fibrosis, and investigated the possible role of miR-140-3p/FOXP1/Smad axis in anti-fibrotic properties of UCMSC-exo. UCMSC-exo were isolated and identified. Transforming growth factor-β (TGF-β) was used to induce human endometrial stromal cell (HESC) fibrosis. Dual luciferase assay was performed to verify the relationship between miR-140-3p and FOXP1. The expressions of fibrotic markers, SIP1, and p-Smad2/p-Smad3 in HESCs stimulated with UCMSC-exo were detected by western blot. In addition, the effects of miR-140-3p mimic, miR-140-3p inhibitor and FOXP1 over-expression on endometrial fibrosis were assessed. The isolated UCMSC-exo had a typical cup-shaped morphology and could be internalized into HESCs. The expressions of fibrotic markers were significantly increased by TGF-β, which was reversed by UCMSC-exo. MiR-140-3p in UCMSC-exo ameliorated TGf-β-induced HESCs fibrosis. FOXP1 was identified as the direct target of miR-140-3p, which could inversely regulate miR-140-3p's function on HESCs fibrosis. Furthermore, we demonstrated that miR-140-3p in UCMSC-exo regulated Smad signal pathway to exert the anti-fibrotic effect in HESCs. The anti-fibrotic effect of UCMSC-derived exosomes against HESC fibrosis was at least partially achieved by miR-140-3p/FOXP1/Smad axis.

3D bioprinting of stromal cells-laden artificial cornea based on visible light-crosslinkable bioinks forming multilength networks

3D bioprinting has the potential for the rapid and precise engineering of hydrogel constructs that can mimic the structural and optical complexity of a healthy cornea. However, the use of existing light-activated bioinks for corneal printing is limited by their poor cytocompatibility, use of cytotoxic photoinitiators (PIs), low photo-crosslinking efficiency, and opaque/colored surface of the printed material. Herein, we report a fast-curable, non-cytotoxic, optically transparent bioprinting system using a new water-soluble benzoyl phosphinate-based PI and photocrosslinkable methacrylated hyaluronic acid (HAMA). Compared with commercially available PIs, the newly developed PI, lithium benzoyl (phenyl) phosphinate (BP), demonstrated increased photoinitiation efficiency under visible light and low cytotoxicity. Using a catalytic amount of BP, the HA-based bioinks quickly formed 3D hydrogel constructs under low-energy visible-light irradiation (405 nm, <1 J cm-2). The mechanical properties and printability of photocurable bioinks were further improved by blending low (10 kDa) and high (100 kDa) molecular weight (MW) HAMA by forming multilength networks. For potential applications as corneal scaffolds, stromal cell-laden dome-shaped constructs were fabricated using MW-blended HAMA/BP bioink and a digital light processing printer. The HA-based photocurable bioinks exhibited good cytocompatibility (80%-95%), fast curing kinetics (<5 s), and excellent optical transparency (>90% in the visible range), potentially making them suitable for corneal tissue engineering.

Bone formation by human paediatric marrow stromal cells in a functional allogeneic immune system

Allogeneic stem-cell based regenerative medicine is a promising approach for bone defect repair. The use of chondrogenically differentiated human marrow stromal cells (MSCs) has been shown to lead to bone formation by endochondral ossification in immunodeficient pre-clinical models. However, an insight into the interactions between the allogeneic immune system and the human MSC-derived bone grafts has not been fully achieved yet. The choice of a potent source of MSCs isolated from pediatric donors with consistent differentiation and high proliferation abilities, as well as low immunogenicity, could increase the chance of success for bone allografts. In this study, we employed an immunodeficient animal model humanised with allogeneic immune cells to study the immune responses towards chondrogenically differentiated human pediatric MSCs (ch-pMSCs). We show that ch-differentiated pMSCs remained non-immunogenic to allogeneic CD4 and CD8 T cells in an in vitro co-culture model. After subcutaneous implantation in mice, ch-pMSC-derived grafts were able to initiate bone mineralisation in the presence of an allogeneic immune system for 3 weeks without the onset of immune responses. Re-exposing the splenocytes of the humanised animals to pMSCs did not trigger further T cell proliferation, suggesting an absence of secondary immune responses. Moreover, ch-pMSCs generated mature bone after 8 weeks of implantation that persisted for up to 6 more weeks in the presence of an allogeneic immune system. These data collectively show that human allogeneic chondrogenically differentiated pediatric MSCs might be a safe and potent option for bone defect repair in the tissue engineering and regenerative medicine setting.

Mesenchymal stem/stromal cells armored by FGF21 ameliorate alcohol-induced liver injury through modulating polarization of macrophages

BACKGROUND

Alcohol-associated liver disease (ALD) is a major health care challenge worldwide with limited therapeutic options. Although mesenchymal stem/stromal cells (MSCs) represent a newly emerging therapeutic approach to treat ALD, thus far, there have been extensive efforts to try and enhance their efficacy, including genetically engineering MSCs. FGF21, an endocrine stress-responsive hormone, has been shown to regulate energy balance, glucose, and lipid metabolism and to enhance the homing of MSCs toward injured sites. Therefore, the purpose of this study was to investigate whether MSCs that overexpress FGF21 (FGF21-MSCs) improve the therapeutic effect of MSCs in treating ALD.

METHODS

Human umbilical cord-derived MSCs served as the gene delivery vehicle for the FGF21 gene. Human umbilical cord-derived MSCs were transduced with the FGF21 gene using lentiviral vectors to mediate FGF21 overexpression. We utilized both chronic Lieber-DeCarli and Gao-binge models of ethanol-induced liver injury to observe the therapeutic effect of FGF21-MSCs. Liver injury was phenotypically evaluated by performing biochemical methods, histology, and inflammatory cytokine levels.

RESULTS

Compared with MSCs alone, administration of MSCs overexpressing FGF21(FGF21-MSCs) treatment significantly enhanced the therapeutic effect of ALD in mice, as indicated by the alleviation of liver injury with reduced steatosis, inflammatory infiltration, oxidative stress, and hepatic apoptosis, and the promotion of liver regeneration. Mechanistically, FGF21 could facilitate the immunomodulatory function of MSCs on macrophages by setting metabolic commitment for oxidative phosphorylation, which enables macrophages to exhibit anti-inflammatory inclination.

CONCLUSIONS

Our data elucidate that MSC modification by FGF21 could enhance their therapeutic effect in ALD and may help in the exploration of effective MSCs-based cell therapies for the treatment of ALD.

Ex vivo expansion of hematopoietic stem cells in two/ three-dimensional co-cultures with various source of stromal cells

The ex vivo expansion of hematopoietic stem cells, with both high quantities and quality, is considered a paramount issue in cell and gene therapy for hematological diseases. Complex interactions between the bone marrow microenvironment and hematopoietic stem cells reveal the importance of using 2D and 3D coculture as a physiological system simulator in the proliferation, differentiation, and homeostasis of HSCs. Herein, the capacity of mesenchymal stem cells derived from different sources to support the expansion and maintenance of HSPC was compared with each other. We evaluated the fold increase of HSPC, CD34 marker expression, cytokine secretion profile of different MSCs, and the frequency of hematopoietic colony-forming unit parameters. Our results show that there was no significant difference between adipose tissue-MSC, Wharton jelly-MSC, and Endometrial-MSCs in HSPC expansion (fold increase: 34.74±4.38 in Wj-MSC, 32.22±5.07 in AD-MSC, 25.9±1.27 in En-MSCs); However, there were significantly more than the expansion media alone (4.4±0.69). The results obtained from the cytokine secretion analysis also confirm these results. Also, there were significant differences in the clonogenicity of Wj-MSC, En-MSCs, and expansion media (CFU-GEMM: 7±1.73, 2.3±1.15, and 2.3±1.52), which indicated that Wj-MSC could significantly maintain the primitive state. As a result, using Wj-mesenchymal stem cells on a 3D coculture system effectively increases the HSPC expansion and maintains the colonization potential of hematopoietic stem cells.

Generation of 3D melanoma models using an assembloid-based approach

While 3D tumor models have greatly evolved over the past years, there is still a strong requirement for more biosimilar models which are capable of recapitulating cellular crosstalk within the tumor microenvironment while equally displaying representative levels of tumor aggressiveness and invasion. Herein, we disclose an assembloid melanoma model based on the fusion of individual stromal multicellular spheroids (MCSs). In contrast to more traditional tumor models, we show that it is possible to develop self-organizing, heterotypic melanoma models where tumor cells present stem-cell like features like up-regulated pluripotency master regulators SOX2, POU5F1 and NANOG. Additionally, these assembloids display high levels of invasiveness while embedded in 3D matrices as evidenced by stromal cell promotion of melanoma cell invasion via metalloproteinase production. Furthermore, sensitivity to anticancer drug doxorubicin was demonstrated for the melanoma assembloid model. These findings suggest that melanoma assembloids may play a significant role in the field of 3D cancer models as they more closely mimic the tumor microenvironment when compared to more traditional MCSs, opening the doors to a better understanding of the role of tumor microenvironment in supporting tumor progression. STATEMENT OF SIGNIFICANCE: The development of complex 3D tumor models that better recapitulate the tumor microenvironment is crucial for both an improved comprehension of intercellular crosstalk and for more efficient drug screening. We have herein developed a self-organizing heterotypic assembloid-based melanoma model capable of closely mimicking the tumor microenvironment. Key features recapitulated were the preservation of cancer cell stemness, sensitivity to anti-cancer agents and tumor cell invasion promoted by stromal cells. The approach of pre-establishing distinct stromal domains for subsequent combination into more complex tumor constructs provides a route for developing superior tumor models with a higher degree of similarity to native cancer tissues.

Elevated levels of plasma inactive stromal cell derived factor-1α predict poor long-term outcomes in diabetic patients following percutaneous coronary intervention

BACKGROUND

Since the complication of diabetes mellitus (DM) is a risk for adverse cardiovascular outcomes in patients with coronary artery disease (CAD), appropriate risk estimation is needed in diabetic patients following percutaneous coronary intervention (PCI). However, there is no useful biomarker to predict outcomes in this population. Although stromal cell derived factor-1α (SDF-1α), a circulating chemokine, was shown to have cardioprotective roles, the prognostic impact of SDF-1α in diabetic patients with CAD is yet to be fully elucidated. Moreover, roles of SDF-1α isoforms in outcome prediction remain unclear. Therefore, this study aimed to assess the prognostic implication of three forms of SDF-1α including total, active, and inactive forms of SDF-1α in patients with DM and after PCI.

METHODS

This single-center retrospective analysis involved consecutive patients with diabetes who underwent PCI for the first time between 2008 and 2018 (n = 849). Primary and secondary outcome measures were all-cause death and the composite of cardiovascular death, non-fatal myocardial infarction, and ischemic stroke (3P-MACE), respectively. For determining plasma levels of SDF-1α, we measured not only total, but also the active type of SDF-1α by ELISA. Inactive isoform of the SDF-1α was calculated by subtracting the active isoform from total SDF-1α.

RESULTS

Unadjusted Kaplan-Meier analyses revealed increased risk of both all-cause death and 3P-MACE in patients with elevated levels of inactive SDF-1α. However, plasma levels of total and active SDF-1α were not associated with cumulative incidences of outcome measures. Multivariate Cox hazard analyses repeatedly indicated the 1 higher log-transformed inactive SDF-1α was significantly associated with increased risk of all-cause death (hazard ratio (HR): 2.64, 95% confidence interval (CI): 1.28-5.34, p = 0.008) and 3P-MACE (HR: 2.51, 95% CI: 1.12-5.46, p = 0.02). Moreover, the predictive performance of inactive SDF-1α was higher than that of total SDF-1α (C-statistics of inactive and total SDF-1α for all-cause death: 0.631 vs 0.554, for 3P-MACE: 0.623 vs 0.524, respectively).

CONCLUSION

The study results indicate that elevated levels of plasma inactive SDF-1α might be a useful indicator of poor long-term outcomes in diabetic patients following PCI.

TRIAL REGISTRATION

This study describes a retrospective analysis of a prospective registry database of patients who underwent PCI at Juntendo University Hospital, Tokyo, Japan (Juntendo Physicians' Alliance for Clinical Trials, J-PACT), which is publicly registered (University Medical Information Network Japan-Clinical Trials Registry, UMIN-CTR 000035587).

Development of a Mouse Experimental System for the In Vivo Characterization of Bioengineered Adipose-Derived Stromal Cells

Human adipose-derived stromal cells (ADSCs) are an important resource for cell-based therapies. However, the dynamics of ADSCs after transplantation and their mechanisms of action in recipients remain unclear. Herein, we generated genetically engineered mouse ADSCs to clarify their biodistribution and post-transplantation status and to analyze their role in recipient mesenchymal tissue modeling. Immortalized ADSCs (iADSCs) retained ADSC characteristics such as stromal marker gene expression and differentiation potential. iADSCs expressing a fluorescent reporter gene were seeded into biocompatible nonwoven fabric sheets and transplanted into the dorsal subcutaneous region of neonatal mice. Transplanted donor ADSCs were distributed as CD90-positive stromal cells on the sheets and survived 1 month after transplantation. Although accumulation of T lymphocytes or macrophages inside the sheet was not observed with or without donor cells, earlier migration and accumulation of recipient blood vascular endothelial cells (ECs) inside the sheet was observed in the presence of donor cells. Thus, our mouse model can help in studying the interplay between donor ADSCs and recipient cells over a 1-month period. This system may be of value for assessing and screening bioengineered ADSCs in vivo for optimal cell-based therapies.

Chronic arsenic exposure affects stromal cells and signaling in the small intestine in a sex-specific manner

Arsenic is a toxicant that is ingested through drinking water and food, exposing nearly 140 million people to levels above the 10 ppb guideline concentration. Studies have shown that arsenic affects intestinal stem cells (ISCs), but the mechanisms by which arsenic alters the formation of adult cells in the small intestine are not well understood. Signals derived from intestinal stromal cells initiate and maintain differentiation. The goal of this study is to evaluate arsenic's effect on intestinal stromal cells, including PdgfrαLo trophocytes, located proximal to the ISCs, and PdgfrαHi telocytes, located proximal to the transit-amplifying region and up the villi. Adult Sox9tm2Crm-EGFP mice were exposed to 0, 33, and 100 ppb sodium arsenite in their drinking water for 13 weeks, and sections of duodenum were examined. Flow cytometry indicated that arsenic exposure dose-responsively reduced Sox9+ epithelial cells and trended toward increased Pdgfrα+ cells. The trophocyte marker, CD81, was reduced by 10-fold and 9.0-fold in the 100 ppb exposure group in male and female mice, respectively. Additionally, a significant 2.2- to 3.1-fold increase in PdgfrαLo expression was found in male mice in trophocytes and Igfbp5+ cells. PdgfrαHi protein expression, a telocyte marker, was more prevalent along the villus/crypt structure in females, whereas Gli1 expression (telocytes) was reduced in male mice exposed to arsenic. Principle coordinate analysis confirmed the sex-dependent response to arsenic exposure, with an increase in trophocyte and decrease in telocyte marker expression observed in male mice. These results imply that arsenic alters intestinal mesenchymal cells in a sex-dependent manner.

A division-of-labor mode contributes to the cardioprotective potential of mesenchymal stem/stromal cells in heart failure post myocardial infarction

Background

Treatment of heart failure post myocardial infarction (post-MI HF) with mesenchymal stem/stromal cells (MSCs) holds great promise. Nevertheless, 2-dimensional (2D) GMP-grade MSCs from different labs and donor sources have different therapeutic efficacy and still in a low yield. Therefore, it is crucial to increase the production and find novel ways to assess the therapeutic efficacy of MSCs.

Materials and methods

hUC-MSCs were cultured in 3-dimensional (3D) expansion system for obtaining enough cells for clinical use, named as 3D MSCs. A post-MI HF mouse model was employed to conduct in vivo and in vitro experiments. Single-cell and bulk RNA-seq analyses were performed on 3D MSCs. A total of 125 combination algorithms were leveraged to screen for core ligand genes. Shinyapp and shinycell workflows were used for deploying web-server.

Result

3D GMP-grade MSCs can significantly and stably reduce the extent of post-MI HF. To understand the stable potential cardioprotective mechanism, scRNA-seq revealed the heterogeneity and division-of-labor mode of 3D MSCs at the cellular level. Specifically, scissor phenotypic analysis identified a reported wound-healing CD142+ MSCs subpopulation that is also associated with cardiac protection ability and CD142- MSCs that is in proliferative state, contributing to the cardioprotective function and self-renewal, respectively. Differential expression analysis was conducted on CD142+ MSCs and CD142- MSCs and the differentially expressed ligand-related model was achieved by employing 125 combination algorithms. The present study developed a machine learning predictive model based on 13 ligands. Further analysis using CellChat demonstrated that CD142+ MSCs have a stronger secretion capacity compared to CD142- MSCs and Flow cytometry sorting of the CD142+ MSCs and qRT-PCR validation confirmed the significant upregulation of these 13 ligand factors in CD142+ MSCs.

Conclusion

Clinical GMP-grade 3D MSCs could serve as a stable cardioprotective cell product. Using scissor analysis on scRNA-seq data, we have clarified the potential functional and proliferative subpopulation, which cooperatively contributed to self-renewal and functional maintenance for 3D MSCs, named as "division of labor" mode of MSCs. Moreover, a ligand model was robustly developed for predicting the secretory efficacy of MSCs. A user-friendly web-server and a predictive model were constructed and available (https://wangxc.shinyapps.io/3D_MSCs/).

Synaptic endocytosis in adult adipose stromal cell-derived neurons

Synapses are essential for facilitating the transmission of information between neurons and for executing neurophysiological processes. Following the exocytosis of neurotransmitters, the synaptic vesicle may quickly undergo endocytosis to preserve the structural integrity of the synapse. When converting adipose-derived stromal cells (ADSCs) into neurons, the ADSCs have already demonstrated comparable morphology, structure, and electrophysiological characteristics to neurons. Nevertheless, there is currently no published study on the endocytotic function of neurons that are produced from ADSCs. This study aimed to examine synaptic endocytosis in neurons derived from ADSCs by qualitatively and quantitatively analyzing the presence of Ap-2, Clathrin, Endophilin, Dynamin, and Hsc70, which are the key proteins involved in clathrin-mediated endocytosis (CME), as well as by using FM1-43 and cadmium selenide quantum dots (CdSe QDs). Additionally, single-cell RNA sequencing (scRNA-seq) was used to look at the levels of both neuronal markers and markers related to CME at the same time. The results of this study provide evidence that synapses in neurons produced from ADSCs have a role in endocytosis, mainly through the CME route.

Protocol for the establishment and characterization of an endometrial-derived epithelial organoid and stromal cell co-culture system

Postnatal development of the uterus involves the specification of undifferentiated epithelium into uterine-type epithelium. That specification is regulated by stromal-epithelial interactions as well as intrinsic cell-specific transcription factors and gene regulatory networks. Here, we present a co-culture system to study the effects of stromal-derived factors on epithelial cell growth and differentiation into organoids. First, we describe epithelial cell isolation and organoid growth characterization. Second, we detail a co-culture system that allows the study of stromal-derived paracrine factors on epithelial development. For complete details on the use and execution of this protocol, please refer to Rizo et al.1.

Cellular interactions in tumor microenvironment during breast cancer progression: new frontiers and implications for novel therapeutics

The breast cancer tumor microenvironment (TME) is dynamic, with various immune and non-immune cells interacting to regulate tumor progression and anti-tumor immunity. It is now evident that the cells within the TME significantly contribute to breast cancer progression and resistance to various conventional and newly developed anti-tumor therapies. Both immune and non-immune cells in the TME play critical roles in tumor onset, uncontrolled proliferation, metastasis, immune evasion, and resistance to anti-tumor therapies. Consequently, molecular and cellular components of breast TME have emerged as promising therapeutic targets for developing novel treatments. The breast TME primarily comprises cancer cells, stromal cells, vasculature, and infiltrating immune cells. Currently, numerous clinical trials targeting specific TME components of breast cancer are underway. However, the complexity of the TME and its impact on the evasion of anti-tumor immunity necessitate further research to develop novel and improved breast cancer therapies. The multifaceted nature of breast TME cells arises from their phenotypic and functional plasticity, which endows them with both pro and anti-tumor roles during tumor progression. In this review, we discuss current understanding and recent advances in the pro and anti-tumoral functions of TME cells and their implications for developing safe and effective therapies to control breast cancer progress.

Mesenchymal stem/stromal cells from human pluripotent stem cell-derived brain organoid enhance the ex vivo expansion and maintenance of hematopoietic stem/progenitor cells

BACKGROUND

Mesenchymal stem/stromal cells (MSCs) are of great therapeutic value due to their role in maintaining the function of hematopoietic stem/progenitor cells (HSPCs). MSCs derived from human pluripotent stem cells represent an ideal alternative because of their unlimited supply. However, the role of MSCs with neural crest origin derived from HPSCs on the maintenance of HSPCs has not been reported.

METHODS

Flow cytometric analysis, RNA sequencing and differentiation ability were applied to detect the characteristics of stromal cells from 3D human brain organoids. Human umbilical cord blood CD34+ (UCB-CD34+) cells were cultured in different coculture conditions composed of stromal cells and umbilical cord MSCs (UC-MSCs) with or without a cytokine cocktail. The hematopoietic stroma capacity of stromal cells was tested in vitro with the LTC-IC assay and in vivo by cotransplantation of cord blood nucleated cells and stroma cells into immunodeficient mice. RNA and proteomic sequencing were used to detect the role of MSCs on HSPCs.

RESULTS

The stromal cells, derived from both H1-hESCs and human induced pluripotent stem cells forebrain organoids, were capable of differentiating into the classical mesenchymal-derived cells (osteoblasts, chondrocytes, and adipocytes). These cells expressed MSC markers, thus named pluripotent stem cell-derived MSCs (pMSCs). The pMSCs showed neural crest origin with CD271 expression in the early stage. When human UCB-CD34+ HSPCs were cocultured on UC-MSCs or pMSCs, the latter resulted in robust expansion of UCB-CD34+ HSPCs in long-term culture and efficient maintenance of their transplantability. Comparison by RNA sequencing indicated that coculture of human UCB-CD34+ HSPCs with pMSCs provided an improved microenvironment for HSC maintenance. The pMSCs highly expressed the Wnt signaling inhibitors SFRP1 and SFRP2, indicating that they may help to modulate the cell cycle to promote the maintenance of UCB-CD34+ HSPCs by antagonizing Wnt activation.

CONCLUSIONS

A novel method for harvesting MSCs with neural crest origin from 3D human brain organoids under serum-free culture conditions was reported. We demonstrate that the pMSCs support human UCB-HSPC expansion in vitro in a long-term culture and the maintenance of their transplantable ability. RNA and proteomic sequencing indicated that pMSCs provided an improved microenvironment for HSC maintenance via mechanisms involving cell-cell contact and secreted factors and suppression of Wnt signaling. This represents a novel method for large-scale production of MSCs of neural crest origin and provides a potential approach for development of human hematopoietic stromal cell therapy for treatment of dyshematopoiesis.

Adipose Stromal Cell-Derived Cancer-Associated Fibroblasts Suppress FGFR Inhibitor Efficacy

Cancer aggressiveness has been linked with obesity, and studies have shown that adipose tissue can enhance cancer progression. In this issue of Cancer Research, Hosni and colleagues discover a paracrine mechanism mediated by adipocyte precursor cells through which urothelial carcinomas become resistant to erdafitinib, a recently approved therapy inhibiting fibroblast growth factor receptors (FGFR). They identified neuregulin 1 (NRG1) secreted by adipocyte precursor cells as an activator of HER3 signaling that enables resistance. The NRG1-mediated FGFR inhibitor resistance was amenable to intervention with pertuzumab, an antibody blocking the NRG1/HER3 axis. To investigate the nature of the resistance-associated NRG1-expressing cells in human patients, the authors analyzed published single-cell RNA sequencing data and observed that such cells appear in a cluster assigned as inflammatory cancer-associated fibroblasts (iCAF). Notably, the gene signature corresponding to these CAFs is highly similar to that shared by adipose stromal cells (ASC) in fat tissue and fibro-adipogenic progenitors (FAP) in skeletal muscle of cancer-free individuals. Because fibroblasts with the ASC/FAP signature are enriched in various carcinomas, it is possible that the paracrine signaling conferred by NRG1 is a pan-cancer mechanism of FGFR inhibitor resistance and tumor aggressiveness. See related article by Hosni et al., p. 725.

Imaging in gynecological disease (27): clinical and ultrasound characteristics of recurrent ovarian stromal cell tumors

OBJECTIVE

To describe the clinical and ultrasound characteristics of recurrent granulosa cell and Sertoli-Leydig cell tumors.

METHODS

This was a retrospective observational study performed at Fondazione Policlinico Universitario A. Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico, IRCCS, Rome (Gemelli center), Italy. Patients with a histological diagnosis of recurrent granulosa cell tumor or Sertoli-Leydig cell tumor were identified from the database of the Department of Gynecological Oncology. Those who had undergone a preoperative ultrasound examination at the Gemelli center between 2012 and 2020 were included, and the data retrieved from the original ultrasound reports. In all of these reports, the recurrent tumors were described using International Ovarian Tumor Analysis (IOTA) terminology. If a patient had more than one episode of relapse, information from all episodes was collected. If there was more than one recurrent tumor at the same ultrasound examination, all tumors were included. One expert sonographer also reviewed all available ultrasound images to identify typical ultrasound patterns using pattern recognition.

RESULTS

We identified 30 patients with a histological diagnosis of recurrent granulosa cell tumor (25 patients, 55 tumors) or Sertoli-Leydig cell tumor (five patients, seven tumors). All 30 had undergone at least one preoperative ultrasound examination at the Gemelli center and were included. These women had a total of 66 episodes of relapse, of which a preoperative ultrasound examination had been performed at the Gemelli center in 34, revealing 62 recurrent lesions: one in 22/34 (64.7%) episodes of relapse, two in 4/34 (11.8%) episodes and three or more in 8/34 (23.5%) episodes. Most recurrent granulosa cell tumors (38/55, 69.1%) and recurrent Sertoli-Leydig tumors (6/7, 85.7%) were classified as solid or multilocular-solid tumors, while 8/55 (14.5%) recurrent granulosa cell tumors and 1/7 (14.3%) recurrent Sertoli-Leydig cell tumors were unilocular cysts and 9/55 (16.4%) recurrent granulosa cell tumors were multilocular cysts. The nine unilocular cysts had contents that were anechoic (n = 2) or had low-level echogenicity (n = 7), had either smooth (n = 4) or irregular (n = 5) internal cyst walls, and ranged in largest diameter from 8 to 38 mm, with three being < 20 mm and five being 20-30 mm. On retrospective review of the images, two typical ultrasound patterns were described: small solid tumor measuring < 2 cm (15/62, 24.2%) and tumor with vascularized echogenic ground-glass-like content (12/62, 19.4%).

CONCLUSIONS

Some granulosa cell and Sertoli-Leydig cell recurrences manifest one of two typical ultrasound patterns, while some appear as unilocular cysts. These are usually classified as benign, but in patients being followed up for a granulosa cell tumor or Sertoli-Leydig cell tumor, a unilocular cyst should be considered suspicious of recurrence. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

The Effect of Lanthanum (III) Nitrate on the Osteogenic Differentiation of Mice Bone Marrow Stromal Cells

To study the species of lanthanum (III) nitrate (La[NO3]3) dispersed in cell media and the effect on the osteoblast differentiation of bone marrow stroma cells (BMSCs). Different La-containing precipitations were obtained by adding various concentrations of La(NO3)3 solutions to Dulbecco's modified Eagle medium (DMEM) or DMEM with fetal bovine serum (FBS). A series of characterisation methods, including dynamic light scattering, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and protein quantification were employed to clarify the species of the different La-containing precipitations. The primary BMSCs were isolated, and the cell viability, alkaline phosphatase activity, and the formation of a mineralised nodule of BMSCs were tested when treated with different La-containing precipitations. The La(NO3)3 solutions in DMEM could form LaPO4, which exits in the particle formation, while the La(NO3)3 solutions in DMEM with FBS could form a La-PO4-protein compound. When treated with La(NO3)3 solutions in DMEM, the cell viability of the BMSCs was inhibited at the concentrations of 1, 10, and 100 μM at 1 day and 3 days. Meanwhile, the supernatant derived from the La(NO3)3 solutions in DMEM did not affect the cell viability of the BMSCs. In addition, the precipitate derived from the La(NO3)3 solutions in DMEM added to the complete medium inhibited the cell viability of the BMSCs at concentrations of 10 μM and 100 μM. When treated with La(NO3)3 solutions in DMEM with FBS, the derived precipitate and supernatant did not affect the cell viability of the BMSCs, except for the concentration of 100 μM La(NO3)3. The La-PO4-protein formed from the La(NO3)3 solutions in DMEM with FBS inhibited the osteoblast differentiation of BMSCs at the concentration of 1 μM La(NO3)3 (P < 0.05) but had no effect on either the osteoblast differentiation at the concentrations of 0.001 and 0.1 μM or on the formation of a mineralised nodule at all tested concentrations of La(NO3)3. Overall, La(NO3)3 solutions in different cell culture media could form different La-containing compounds: La-PO4 particles (in DMEM) and a La-PO4-protein compound (in DMEM with FBS). The different La-containing compounds caused different effects on the cell viability, osteoblast differentiation, and the formation of a mineralised nodule of the BMSCs. The La-containing precipitation inhibited the osteoblast differentiation by inhibiting the expression of osteoblast-related genes and proteins, providing a theoretical basis for clinical doctors to apply phosphorus-lowering drugs such as lanthanum carbon.

Processing methods for human amniotic membrane as scaffold for tissue engineering with mesenchymal stromal human cells

Tissue engineering is an interdisciplinary field that applies the principles of engineering and life sciences toward the development of biological substitutes that restore, maintain, or improve tissue function. The aims of this work were to compare chemically and physically processed human Amniotic Membranes (hAM) and analyze the cytocompatibility and proliferation rate (PR) of two primary human mesenchymal stromal cell lines, from different sources and donor conditions seeded over these scaffolds. The evaluated hAM processes were: cold shock to obtain a frozen amniotic membrane (FEAM) with remaining dead epithelial cells, denudation of hAM with trypsin for 20/10 min (DEAM20/10) or treatment with sodium dodecyl sulfate to decellularized hAM (DAM). All samples were sterilized with gamma radiation. The selection of the treated hAM to then generate composites was performed by scanning and transmission electron microscopy and characterization by X-ray diffraction, selecting DEAM10 and FEAM as scaffolds for cell seeding. Two sources of primary human stromal cells were used, both developed by our researchers, human Dental Pulp Stem Cells (hDPSC) from living donors and human Mesenchymal Stromal Cells (hMSC) from bone marrow isolated from brain dead donors. This last line of cells conveys a novel source of human cells that, to our knowledge, have not been tested as part of this type of construct. We developed four in vitro constructs without cytotoxicity signs and with different PR depending on the scaffolds and cells. hDPSC and hMSC grew over both FEAM and DEAM10, but DEAM10 allowed higher PR.

MarShie: a clearing protocol for 3D analysis of single cells throughout the bone marrow at subcellular resolution

Analyzing immune cell interactions in the bone marrow is vital for understanding hematopoiesis and bone homeostasis. Three-dimensional analysis of the complete, intact bone marrow within the cortex of whole long bones remains a challenge, especially at subcellular resolution. We present a method that stabilizes the marrow and provides subcellular resolution of fluorescent signals throughout the murine femur, enabling identification and spatial characterization of hematopoietic and stromal cell subsets. By combining a pre-processing algorithm for stripe artifact removal with a machine-learning approach, we demonstrate reliable cell segmentation down to the deepest bone marrow regions. This reveals age-related changes in the marrow. It highlights the interaction between CX3CR1+ cells and the vascular system in homeostasis, in contrast to other myeloid cell types, and reveals their spatial characteristics after injury. The broad applicability of this method will contribute to a better understanding of bone marrow biology.

Temporal dynamics of immune-stromal cell interactions in fracture healing

Bone fracture repair is a complex, multi-step process that involves communication between immune and stromal cells to coordinate the repair and regeneration of damaged tissue. In the US, 10% of all bone fractures do not heal properly without intervention, resulting in non-union. Complications from non-union fractures are physically and financially debilitating. We now appreciate the important role that immune cells play in tissue repair, and the necessity of the inflammatory response in initiating healing after skeletal trauma. The temporal dynamics of immune and stromal cell populations have been well characterized across the stages of fracture healing. Recent studies have begun to untangle the intricate mechanisms driving the immune response during normal or atypical, delayed healing. Various in vivo models of fracture healing, including genetic knockouts, as well as in vitro models of the fracture callus, have been implemented to enable experimental manipulation of the heterogeneous cellular environment. The goals of this review are to (1): summarize our current understanding of immune cell involvement in fracture healing (2); describe state-of-the art approaches to study inflammatory cells in fracture healing, including computational and in vitro models; and (3) identify gaps in our knowledge concerning immune-stromal crosstalk during bone healing.

Sfrp1 as a Pivotal Paracrine Factor in the Trained Pericardial Stem Cells that Foster Reparative Activity

Tissue damage often induces local inflammation that in turn dictates a series of subsequential responses, such as stem cell activation and growth, to maintain tissue homeostasis. The aim of the study is to testify the possibility of using inflammation-trained stem cells as optimal donor cells to augment the efficacy of cell therapy. The pericardial stem/stromal cells derived from the animals after myocardial infarction (MI-pSC) showed an enhanced myogenic potential and augmented reparative activity after transplantation in the injured hearts, as compared to the Sham-pSC. Bulk RNA-Seq analysis revealed significant upregulation of a panel of myogenic and trophic genes in the MI-pSC and, notably, Sfrp1 as an important anti-apoptotic factor induced robustly in the MI-pSC. Injection of the MI-pSC yielded measurable numbers of surviving cardiomyocytes (Tunel and Casp-3 negative) within the infarct area, but the effects were significantly diminished by siRNA-based silence of Sfrp1 gene in the pSC. Primed Sham-pSC with pericardial fluid from MI rats mimicked the upregulation of Sfrp1 and enhanced myogenic potential and reparative activity of pSC. Taken together, our results illustrated the inflammation-trained pSC favor a reparative activity through upregulation of Sfrp1 gene that confers anti-apoptotic activity in the injured cardiomyocytes. Therefore, the active form of stem cells may be used as a cardiac protective agent to boost therapeutical potential of stem cells.

Highly Concentrated Stabilized Hybrid Complexes of Hyaluronic Acid: Rheological and Biological Assessment of Compatibility with Adipose Tissue and Derived Stromal Cells towards Regenerative Medicine

Cells and extracts derived from adipose tissue are gaining increasing attention not only in plastic surgery and for aesthetic purposes but also in regenerative medicine. The ability of hyaluronan (HA) to support human adipose stromal cell (hASC) viability and differentiation has been investigated. However, the compatibility of adipose tissue with HA-based formulation in terms of biophysical and rheological properties has not been fully addressed, although it is a key feature for tissue integration and in vivo performance. In this study, the biophysical and biochemical properties of highly concentrated (45 mg/mL) high/low-molecular-weight HA hybrid cooperative complex were assessed with a further focus on the potential application in adipose tissue augmentation/regeneration. Specifically, HA hybrid complex rheological behavior was observed in combination with different adipose tissue ratios, and hyaluronidase-catalyzed degradation was compared to that of a high-molecular-weight HA (HHA). Moreover, the HA hybrid complex's ability to induce in vitro hASCs differentiation towards adipose phenotype was evaluated in comparison to HHA, performing Oil Red O staining and analyzing gene/protein expression of PPAR-γ, adiponectin, and leptin. Both treatments supported hASCs differentiation, with the HA hybrid complex showing better results. These outcomes may open new frontiers in regenerative medicine, supporting the injection of highly concentrated hybrid formulations in fat compartments, eventually enhancing residing staminal cell differentiation and improving cell/growth factor persistence towards tissue regeneration districts.

Rethinking the Roles of Cancer-Associated Fibroblasts in Pancreatic Cancer

Bearing a dismal 5-year survival rate, pancreatic ductal adenocarcinoma (PDAC) is a challenging disease that features a unique fibroinflammatory tumor microenvironment. As major components of the PDAC tumor microenvironment, cancer-associated fibroblasts are still poorly understood and their contribution to the several hallmarks of PDAC, such as resistance to therapies, immunosuppression, and high incidence of metastasis, is likely underestimated. There have been encouraging advances in the understanding of these fascinating cells, but many controversies remain, leaving the field still actively exploring the full scope of their contributions in PDAC progression. Here we pose several important considerations regarding PDAC cancer-associated fibroblast functions. We posit that transcriptomic analyses be interpreted with caution, when aiming to uncover the functional contributions of these cells. Moreover, we propose that normalizing these functions, rather than eliminating them, will provide the opportunity to enhance therapeutic response. Finally, we propose that cancer-associated fibroblasts should not be studied in isolation, but in conjunction with its extracellular matrix, because their respective functions are coordinated and concordant.

The comparison of adipose-derived stromal cells (ADSCs) delivery method in a murine model of hindlimb ischemia

BACKGROUND

Adipose-derived stromal cells (ADSCs) demonstrate ability to promote tissue healing and down-regulate excessive inflammation. ADSCs have been used to treat critical limb ischemia in preclinical and clinical trials, but still, there is little known about their optimal delivery strategy. To date, no direct analysis of different methods of ADSCs delivery has been performed in the hindlimb ischemia model. Therefore, in this study we focused on the therapeutic efficacy of different ADSCs delivery methods in a murine model of hindlimb ischemia.

METHODS

For the hADSCs isolation, we used the subcutaneous adipose tissue collected during the surgery. The murine hindlimb ischemia was used as a model. The unilateral femoral artery ligation was performed on 10-12-week-old male C57BL/6. ADSCs were delivered directly into ischemic muscle, into the contralateral muscle or intravenously. 7 and 14 days after the surgery, the gastrocnemius and quadriceps muscles were collected for the immunohistochemical analysis. The results were analyzed with relevant tests using the Statistica software.

RESULTS

Our research revealed that muscle regeneration, angiogenesis, arteriogenesis and macrophage infiltration in murine model of hindlimb ischemia differ depending on ADSCs delivery method. We have demonstrated that intramuscular method (directly into ischemic limb) of ADSCs delivery is more efficient in functional recovery after critical limb ischemia than intravenous or contralateral route.

CONCLUSIONS

We have noticed that injection of ADSCs directly into ischemic limb is the optimal delivery strategy because it increases: (1) muscle fiber regeneration, (2) the number of capillaries and (3) the influx of macrophages F4/80+/CD206+.

A method for isolating and culturing ectopic epithelial and stromal cells to study human adenomyosis

PURPOSE

Although adenomyosis is a common and benign gynecological disease, the specific pathogenesis of this condition is yet to be fully elucidated. It is difficult to culture primary cells of the ectopic endometrial epithelia and stroma from human adenomyosis lesions. Most of the previous of studies on adenomyosis were based on primary eutopic endometrium cells. However, as yet, no efficient protocols have been developed for the isolation, culture or purification of primary ectopic epithelial and stromal cells from human adenomyosis lesions. Therefore, the present study aimed to develop an efficient protocol for the isolation and culture of primary ectopic epithelial and stromal cells from human adenomyosis lesions.

METHODS

In the present study, we aimed to obtain ectopic endometrium tissue from human adenomyosis foci and use a simple and operable type I collagenase digestion method for primary culture. Cells were isolated by sterile cell strainer filtration and flow cytometry was performed to identify, purify, and evaluate the viability of isolated ectopic endometrial cells.

RESULTS

Using our method, we successfully isolated and cultured highly purified and active ectopic endometrial epithelial and stromal cells from human adenomyosis foci. Ep-CAM was expressed in ectopic epithelial cells of human adenomyosis with a purity of 93.74% and a viability of 80.58%. In addition, CD10 were robustly expressed by ectopic stromal cells in human adenomyosis. Cellular purity and viability were determined to be 96.37 and 93.49%, respectively.

CONCLUSION

Our method provides a new experimental model for studying the molecular pathogenesis of human adenomyosis.

Margin status impact on recurrence of phyllodes tumors in high-risk groups: a retrospective observational study

BACKGROUND

Phyllodes tumor (PT) is an fibroepithelial tumor with potential for local recurrence. The optimal margin for surgical resection of PT is still debated, particularly in cases of positive margins. This study aimed to identify the risk factors for phyllodes tumor recurrence and the effect of a free margin on tumor recurrence by considering these risk factors.

MATERIALS AND METHODS

This is a retrospective observational study of patients diagnosed with PT who had undergone surgical management. The data were collected from medical records from 2001 to 2020 in the breast clinic of Shahid Motahhari Clinic of Shiraz. Patients were followed up for at least 3 years after the operation to be checked for local recurrence or distant metastasis at regular intervals.

RESULTS

This retrospective study included 319 patients with PT who underwent surgical management. Of these patients, 83.9% (n = 267), 7.6% (n = 24), and 8.5% (n = 27) were classified as benign, borderline, and malignant, respectively. 8.8% of all patients and 7.6% of non-malignant cases experienced local recurrence, and risk factors for recurrence included oral contraceptive use, smoking, size > 4 cm, stromal overgrowth, and stromal cell atypia. A negative surgical margin decreased the prevalence of recurrence in tumors > 4 cm and with stromal overgrowth significantly.

CONCLUSION

The study found that a negative margin in all patients did not reduce the recurrence rate in benign and borderline phyllodes tumors, suggesting close follow up as a reasonable alternative. However, a negative margin may be effective in reducing recurrence in certain high-risk groups.

Adipose Stromal Cell-Derived Secretome Attenuates Cisplatin-Induced Injury In Vitro Surpassing the Intricate Interplay between Proximal Tubular Epithelial Cells and Macrophages

(1) Background: The chemotherapeutic drug cisplatin exerts toxic side effects causing acute kidney injury. Mesenchymal stromal cells can ameliorate cisplatin-induced kidney injury. We hypothesize that the MSC secretome orchestrates the vicious cycle of injury and inflammation by acting on proximal tubule epithelial cells (PTECs) and macrophages individually, but further by counteracting their cellular crosstalk. (2) Methods: Conditioned medium (CM) from adipose stromal cells was used, first assessing its effect on cisplatin injury in PTECs. Second, the effects of cisplatin and the CM on macrophages were measured. Lastly, in an indirect co-culture system, the interplay between the two cell types was assessed. (3) Results: First, the CM rescued PTECs from cisplatin-induced apoptosis by reducing oxidative stress and expression of nephrotoxicity genes. Second, while cisplatin exerted only minor effects on macrophages, the CM skewed macrophage phenotypes to the anti-inflammatory M2-like phenotype and increased phagocytosis. Finally, in the co-culture system, the CM suppressed PTEC death by inhibiting apoptosis and nuclei fragmentation. The CM lowered TNF-α release, while cisplatin inhibited macrophage phagocytosis, PTECs, and the CM to a greater extent, thus enhancing it. The CM strongly dampened the inflammatory macrophage cytokine secretion triggered by PTECs. (4) Conclusions: ASC-CM surpasses the PTEC-macrophage crosstalk in cisplatin injury. The positive effects on reducing cisplatin cytotoxicity, on polarizing macrophages, and on fine-tuning cytokine secretion underscore MSCs' CM benefit to prevent kidney injury progression.

Distinct mesenchymal cell states mediate prostate cancer progression

In the complex tumor microenvironment (TME), mesenchymal cells are key players, yet their specific roles in prostate cancer (PCa) progression remain to be fully deciphered. This study employs single-cell RNA sequencing to delineate molecular changes in tumor stroma that influence PCa progression and metastasis. Analyzing mesenchymal cells from four genetically engineered mouse models (GEMMs) and correlating these findings with human tumors, we identify eight stromal cell populations with distinct transcriptional identities consistent across both species. Notably, stromal signatures in advanced mouse disease reflect those in human bone metastases, highlighting periostin's role in invasion and differentiation. From these insights, we derive a gene signature that predicts metastatic progression in localized disease beyond traditional Gleason scores. Our results illuminate the critical influence of stromal dynamics on PCa progression, suggesting new prognostic tools and therapeutic targets.

Analyzing the impact of metabolism on immune cells in tumor microenvironment to promote the development of immunotherapy

Tumor metabolism and tumor immunity are inextricably linked. Targeting the metabolism of tumors is a point worth studying in tumor immunotherapy. Recently, the influence of the metabolism of tumors and immune cells on the occurrence, proliferation, metastasis, and prognosis of tumors has attracted more attention. Tumor tissue forms a specific tumor microenvironment (TME). In addition to tumor cells, there are also immune cells, stromal cells, and other cells in TME. To adapt to the environment, tumor cells go through the metabolism reprogramming of various substances. The metabolism reprogramming of tumor cells may further affect the formation of the tumor microenvironment and the function of a variety of cells, especially immune cells, eventually promoting tumor development. Therefore, it is necessary to study the metabolism of tumor cells and its effects on immune cells to guide tumor immunotherapy. Inhibiting tumor metabolism may restore immune balance and promote the immune response in tumors. This article will describe glucose metabolism, lipid metabolism, amino acid metabolism, and immune cells in tumors. Besides, the impact of metabolism on the immune cells in TME is also discussed for analyzing and exploring tumor immunotherapy.

Targeting tumor-stromal interactions in triple-negative breast cancer using a human vascularized micro-tumor model

Triple-negative breast cancer (TNBC) is highly aggressive with limited available treatments. Stromal cells in the tumor microenvironment (TME) are crucial in TNBC progression; however, understanding the molecular basis of stromal cell activation and tumor-stromal crosstalk in TNBC is limited. To investigate therapeutic targets in the TNBC stromal niche, we used an advanced human in vitro microphysiological system called the vascularized micro-tumor (VMT). Using single-cell RNA sequencing, we revealed that normal breast tissue stromal cells activate neoplastic signaling pathways in the TNBC TME. By comparing interactions in VMTs with clinical data, we identified therapeutic targets at the tumor-stromal interface with potential clinical significance. Combining treatments targeting Tie2 signaling with paclitaxel resulted in vessel normalization and increased efficacy of paclitaxel in the TNBC VMT. Dual inhibition of HER3 and Akt also showed efficacy against TNBC. These data demonstrate the potential of inducing a favorable TME as a targeted therapeutic approach in TNBC.

Serial Passaging Affects Stromal Cell Mechanosensitivity on Hyaluronic Acid Hydrogels

There is a tremendous interest in developing hydrogels as tunable in vitro cell culture platforms to study cell response to mechanical cues in a controlled manner. However, little is known about how common cell culture techniques, such as serial expansion on tissue culture plastic, affect subsequent cell behavior when cultured on hydrogels. In this work, a methacrylated hyaluronic acid hydrogel platform is leveraged to study stromal cell mechanotransduction. Hydrogels are first formed through thiol-Michael addition to model normal soft tissue (e.g., lung) stiffness (E ≈ 1 kPa). Secondary cross-linking via radical photopolymerization of unconsumed methacrylates allows matching of early- (E ≈ 6 kPa) and late-stage fibrotic tissue (E ≈ 50 kPa). Early passage (P1) human bone marrow mesenchymal stromal cells (hMSCs) display increased spreading, myocardin-related transcription factor-A (MRTF-A) nuclear localization, and focal adhesion size with increasing hydrogel stiffness. However, late passage (P5) hMSCs show reduced sensitivity to substrate mechanics with lower MRTF-A nuclear translocation and smaller focal adhesions on stiffer hydrogels compared to early passage hMSCs. Similar trends are observed in an immortalized human lung fibroblast line. Overall, this work highlights the implications of standard cell culture practices on investigating cell response to mechanical signals using in vitro hydrogel models.

Cep120 is essential for kidney stromal progenitor cell growth and differentiation

Mutations in genes that disrupt centrosome structure or function can cause congenital kidney developmental defects and lead to fibrocystic pathologies. Yet, it is unclear how defective centrosome biogenesis impacts renal progenitor cell physiology. Here, we examined the consequences of impaired centrosome duplication on kidney stromal progenitor cell growth, differentiation, and fate. Conditional deletion of the ciliopathy gene Cep120, which is essential for centrosome duplication, in the stromal mesenchyme resulted in reduced abundance of interstitial lineages including pericytes, fibroblasts and mesangial cells. These phenotypes were caused by a combination of delayed mitosis, activation of the mitotic surveillance pathway leading to apoptosis, and changes in both Wnt and Hedgehog signaling that are key for differentiation of stromal cells. Cep120 ablation resulted in small hypoplastic kidneys with medullary atrophy and delayed nephron maturation. Finally, Cep120 and centrosome loss in the interstitium sensitized kidneys of adult mice, causing rapid fibrosis after renal injury via enhanced TGF-β/Smad3-Gli2 signaling. Our study defines the cellular and developmental defects caused by loss of Cep120 and aberrant centrosome biogenesis in the embryonic kidney stroma.

The mitochondrial-endoplasmic reticulum co-transfer in dental pulp stromal cell promotes pulp injury repair

Dental pulp injury remains a clinical challenge with limited therapeutic approaches. In the present study, we sought to prove that dental pulp stromal cells (DPSCs) mitochondrial transfer could promote dental pulp injury repair and endoplasmic reticulum (ER)-mitochondrial contacts have a significant regulatory effect on mitochondrial transfer. Healthy DPSCs were co-cultured directly or indirectly with injured DPSCs in the first molar of 1-2 month SD rats or in vitro. Mitochondrial transfer was observed after 24 h of co-culture using fluorescence microscopy and live cell workstation. After co-culture for 1W, 8-OhdG immunofluorescence, mitochondrial membrane potential and total oxidant status/total antioxidant status were used to detect the mitochondrial function of injured DPSCs before and after mitochondrial transfer. Subsequently, mitochondria-ER co-transfer was regulated by modulating mitochondria-ER binding in healthy DPSCs, and the results of GRP78 and CHOP in DPSCs, and PDI immunofluorescence and haematoxylin and eosin staining of pulp tissue were analysed to clarify the effects of modulating mitochondria-ER co-transfer on endoplasmic reticulum stress (ERS), and on pulp injury repair. Fluorescence microscopy and live cell workstation results showed significant mitochondrial transfer between DPSCs. Meanwhile, mitochondrial transfer significantly restored mitochondrial function in injured DPSCs. By modulating mitochondrial-ER binding, the efficiency of mitochondrial transfer between DPSCs was significantly affected and had an impact on ERS in injured cells. Mitochondrial transfer of DPSCs significantly promotes pulpal injury repair and functional recovery of damaged DPSCs, and mitochondrial transfer of DPSCs is regulated by mitochondria-ER binding.

Correlations of Serum Retinol-Binding Protein and Stromal Cell-Derived Factor-1 with Renal Function in Patients with Diabetic Kidney Disease

BACKGROUND

The aim is to investigate the correlations of serum retinol-binding protein (RBP) and stromal cell-derived factor-1 (SDF-1) with renal function in patients with diabetic kidney disease (DKD).

METHODS

A total of 438 patients with type 2 diabetes mellitus (T2DM) treated from October 2017 to October 2020 were enrolled in this prospective study and divided into simple T2DM and DKD groups. According to urinary albumin-to-creatinine ratio (UACR), DKD patients were divided into moderate, severe, and nephrotic groups. They were assigned to one of the following categories of estimated glomerular filtration rate (eGFR): G1, G2, G3a, G3b, G4, and G5 stages. The correlations of RBP and SDF-1 with renal function were analyzed.

RESULTS

The DKD group had a longer T2DM course and higher RBP, uric acid (UA), blood urea nitrogen (BUN), β2-microglobulin (β2-MG), serum creatinine (Scr) levels and UACR, and lower SDF-1 level and eGFR than those of simple T2DM group (p < 0.05). The areas under the receiver operating characteristic curves of RBP and SDF-1 for identifying DKD were 0.903 and 0.868, and the optimal cutoff values were 70.71 mg/L and 5.69 ng/mL, respectively. With increasing urinary albumin and clinical stage, RBP, UA, BUN, β2-MG and Scr levels and UACR significantly rose, while SDF-1 level and eGFR declined (p < 0.05). In patients with DKD, RBP was correlated positively with UACR, UA, BUN, β2-MG, and Scr (r = 0.764/0.787/0.693/0.577/0.801, p < 0.0001), and negatively with eGFR (r = -0.782, p < 0.0001). SDF-1 was correlated negatively with UACR, UA, BUN, β2-MG and Scr (r = -0.744/-0.794/-0.666/-0.605/-0.820, p < 0.0001), and positively with eGFR (r = 0.767, p < 0.0001). The multiple linear regression equation was RBP = 29.852 + 0.007 x UACR + 0.101 x UA + 0.497 x BUN + 0.034 x Scr-0.083 x eGFR (p < 0.001).

CONCLUSIONS

RBP and SDF-1 can identify DKD in patients with T2DM, and the degree of renal function damage is correlated positively with RBP and negatively with SDF-1. Elevated levels of UA, BUN, Scr and UACR as well as reduced eGFR are risk factors for evaluating RBP.

Factors Defining Human Adipose Stem/Stromal Cell Immunomodulation in Vitro

Human adipose tissue-derived stem/stromal cells (hASCs) are adult multipotent mesenchymal stem/stromal cells with immunomodulatory capacities. Here, we present up-to-date knowledge on the impact of different experimental and donor-related factors on hASC immunoregulatory functions in vitro. The experimental determinants include the immunological status of hASCs relative to target immune cells, contact vs. contactless interaction, and oxygen tension. Factors such as the ratio of hASCs to immune cells, the cellular context, the immune cell activation status, and coculture duration are also discussed. Conditioning of hASCs with different approaches before interaction with immune cells, hASC culture in xenogenic or xenofree culture medium, hASC culture in two-dimension vs. three-dimension with biomaterials, and the hASC passage number are among the experimental parameters that greatly may impact the hASC immunosuppressive potential in vitro, thus, they are also considered. Moreover, the influence of donor-related characteristics such as age, sex, and health status on hASC immunomodulation in vitro is reviewed. By analysis of the literature studies, most of the indicated determinants have been investigated in broad non-standardized ranges, so the results are not univocal. Clear conclusions cannot be drawn for the fine-tuned scenarios of many important factors to set a standard hASC immunopotency assay. Such variability needs to be carefully considered in further standardized research. Importantly, field experts' opinions may help to make it clearer.

Stromal bone marrow fibroblasts and mesenchymal stem cells support acute myeloid leukaemia cells and promote therapy resistance

The bone marrow (BM) is the primary site of adult haematopoiesis, where stromal elements (e.g. fibroblasts and mesenchymal stem cells [MSCs]) work in concert to support blood cell development. However, the establishment of an abnormal clone can lead to a blood malignancy, such as acute myeloid leukaemia (AML). Despite our increased understanding of the pathophysiology of the disease, patient survival remains suboptimal, mainly driven by the development of therapy resistance. In this review, we highlight the importance of bone marrow fibroblasts and MSCs in health and acute myeloid leukaemia and their impact on patient prognosis. We discuss how stromal elements reduce the killing effects of therapies via a combination of contact-dependent (e.g. integrins) and contact-independent (i.e. secreted factors) mechanisms, accompanied by the establishment of an immunosuppressive microenvironment. Importantly, we underline the challenges of therapeutically targeting the bone marrow stroma to improve acute myeloid leukaemia patient outcomes, due to the inherent heterogeneity of stromal cell populations. LINKED ARTICLES: This article is part of a themed issue on Cancer Microenvironment and Pharmacological Interventions. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.2/issuetoc.

Endometrial Assembloids to Model Human Embryo Implantation In Vitro

Understanding the process of human embryo implantation is impeded by the inability to study this phenomenon in vivo, thus limiting opportunities to gain knowledge to in vitro modeling. Previous models have relied on monolayer co-cultures, which do not replicate the complexity of endometrial tissue. Here, we detail the establishment of three-dimensional endometrial assembloids, comprising gland-like epithelial organoids in a stromal matrix. Endometrial assembloids mimic endometrial tissue structure more faithfully and can be used to study human embryo-endometrial interactions. Co-cultures of human embryos and endometrial assembloids will enhance our fundamental understanding of these processes as well as allowing us to study the mechanisms of persistent reproductive failure.

Cosmetic Breast Augmentation with Autologous Ex Vivo-Expanded Adipose-Derived Mesenchymal Stem/Stromal Cell (Stemform®)-Enriched Fat Grafts: A Study of the First Twenty-Two Real-World Patients

BACKGROUND

Fat grafting is commonly utilized in breast surgery, and since it was first described, clinicians and researchers have stridden towards improvement of graft retention. Current advancements include adding adipose-derived mesenchymal stem/stromal cells (MSC(AT)s), which have demonstrated promise for improved graft retention.

OBJECTIVES

This study reports outcomes for the first twenty-two patients undergoing breast augmentation (Stemform BA) or artificial implant replacement (Stemform AIR) with MSC(AT)-enriched fat in a real-world setting.

METHODS

Autologous MSC(AT)s were isolated and expanded ex vivo, then mixed with lipoaspirate and injected as enriched fat for Stemform BA and AIR. The breast volume was measured preoperatively and at 3 and 12 months postoperative using a 3D Infinity Dual-Lens Camera and LifeVizApp software. Additionally, independent plastic surgeons evaluated clinical images, and patient satisfaction was obtained at equal time points.

RESULTS

Twenty-two patients were included. All completed 3 and 12 months clinical follow-up and 3 months volume measurements. Nineteen patients completed 12 months volume measurements. The median fat graft retention at 12 months was 95.7% (IQR = 82.44-103.12%) for Stemform BA patients and 113.0% (IQR = 94.8-131.2%) for Stemform AIR patients. The Stemform BA patients had a median breast enlargement of 172.0% (IQR = 156.7-241.0%). The implant replacement volume of Stemform AIR patients was 102% (IQR = 85.1-130.3%). The patient reported 92.8% and 100% would elect to repeat treatment if they had the opportunity for Stemform BA and Stemform AIR, respectively.

CONCLUSION

Breast augmentation and breast implant replacement patients receiving ex vivo-expanded MSC(AT)-enriched fat grafts had high graft retention and patient satisfaction scores. The paper confirms the clinical efficacy of using ex vivo-expanded MSC(AT)s. Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Spider silk enhanced tissue engineering of cartilage tissue: Approach of a novel bioreactor model using adipose derived stromal cells

Human cartilage tissue remains a challenge for the development of therapeutic options due to its poor vascularization and reduced regenerative capacities. There are a variety of research approaches dealing with cartilage tissue engineering. In addition to different biomaterials, numerous cell populations have been investigated in bioreactor-supported experimental setups to improve cartilage tissue engineering. The concept of the present study was to investigate spider silk cocoons as scaffold seeded with adipose-derived stromal cells (ASC) in a custom-made bioreactor model using cyclic axial compression to engineer cartilage-like tissue. For chemical induction of differentiation, BMP-7 and TGF-β2 were added and changes in cell morphology and de-novo tissue formation were investigated using histological staining to verify chondrogenic differentiation. By seeding spider silk cocoons with ASC, a high colonization density and cell proliferation could be achieved. Mechanical induction of differentiation using a newly established bioreactor model led to a more roundish cell phenotype and new extracellular matrix formation, indicating a chondrogenic differentiation. The addition of BMP-7 and TGF-β2 enhanced the expression of cartilage specific markers in immunohistochemical staining. Overall, the present study can be seen as pilot study and valuable complementation to the published literature.

Lymph node stromal cell responses to perinatal T cell waves, a temporal atlas

The perinatal period is a critical time window in establishing T cell tolerance. Regulatory T cells (Tregs) made during the first 2 wk of life are key drivers of perinatal tolerance induction, but how these cells are generated and operate has not been established. To elucidate the unique environment murine perinatal Tregs encounter within the lymph nodes (LNs) as they first emerge from the thymus, and how it evolves over the succeeding days, we employed single-cell RNA sequencing to generate an atlas of the early LN niche. A highly dynamic picture emerged, the stromal cell compartment showing the most striking changes and putative interactions with other LN cell compartments. In particular, LN stromal cells showed increasing potential for lymphocyte interactions with age. Analogous studies on mice lacking α:β T cells or enriched for autoreactive α:β T cells revealed an acute stromal cell response to α:β T cell dysfunction, largely reflecting dysregulation of Tregs. Punctual ablation of perinatal Tregs induced stromal cell activation that was dependent on both interferon-gamma signaling and activation of conventional CD4+ T cells. These findings elucidate some of the earliest cellular and molecular events in perinatal induction of T cell tolerance, providing a framework for future explorations.

Hematopoietic and stromal DMP1-Cre labeled cells form a unique niche in the bone marrow

Skeletogenesis and hematopoiesis are interdependent. Niches form between cells of both lineages where microenvironmental cues support specific lineage commitment. Because of the complex topography of bone marrow (BM), the identity and function of cells within specialized niches has not been fully elucidated. Dentin Matrix Protein 1 (DMP1)-Cre mice have been utilized in bone studies as mature osteoblasts and osteocytes express DMP1. DMP1 has been identified in CXCL12+ cells and an undefined CD45+ population. We crossed DMP1-Cre with Ai9 reporter mice and analyzed the tdTomato+ (tdT+) population in BM and secondary hematopoietic organs. CD45+tdT+ express myeloid markers including CD11b and are established early in ontogeny. CD45+tdT+ cells phagocytose, respond to LPS and are radioresistant. Depletion of macrophages caused a significant decrease in tdT+CD11b+ myeloid populations. A subset of CD45+tdT+ cells may be erythroid island macrophages (EIM) which are depleted after G-CSF treatment. tdT+CXCL12+ cells are in direct contact with F4/80 macrophages, express RANKL and form a niche with B220+ B cells. A population of resident cells within the thymus are tdT+ and express myeloid markers and RANKL. In conclusion, in addition to targeting osteoblast/osteocytes, DMP1-Cre labels unique cell populations of macrophage and stromal cells within BM and thymus niches and expresses key microenvironmental factors.

The Complex Role of the Microbiome in Non-Small Cell Lung Cancer Development and Progression

In recent years, there has been a growing interest in the relationship between microorganisms in the surrounding environment and cancer cells. While the tumor microenvironment predominantly comprises cancer cells, stromal cells, and immune cells, emerging research highlights the significant contributions of microbial cells to tumor development and progression. Although the impact of the gut microbiome on treatment response in lung cancer is well established, recent investigations indicate complex roles of lung microbiota in lung cancer. This article focuses on recent findings on the human lung microbiome and its impacts in cancer development and progression. We delve into the characteristics of the lung microbiome and its influence on lung cancer development. Additionally, we explore the characteristics of the intratumoral microbiome, the metabolic interactions between lung tumor cells, and how microorganism-produced metabolites can contribute to cancer progression. Furthermore, we provide a comprehensive review of the current literature on the lung microbiome and its implications for the metastatic potential of tumor cells. Additionally, this review discusses the potential for therapeutic modulation of the microbiome to establish lung cancer prevention strategies and optimize lung cancer treatment.

Exploring therapeutic avenues: mesenchymal stem/stromal cells and exosomes in confronting enigmatic biofilm-producing fungi

Fungal infections concomitant with biofilms can demonstrate an elevated capacity to withstand substantially higher concentrations of antifungal agents, contrasted with infectious diseases caused by planktonic cells. This inherent resilience intrinsic to biofilm-associated infections engenders a formidable impediment to effective therapeutic interventions. The different mechanisms that are associated with the intrinsic resistance of Candida species encompass drug sequestration by the matrix, drug efflux pumps, stress response cell density, and the presence of persister cells. These persisters, a subset of fungi capable of surviving hostile conditions, pose a remarkable challenge in clinical settings in virtue of their resistance to conventional antifungal therapies. Hence, an exigent imperative has arisen for the development of novel antifungal therapeutics with specific targeting capabilities focused on these pathogenic persisters. On a global scale, fungal persistence and their resistance within biofilms generate an urgent clinical need for investigating recently introduced therapeutic strategies. This review delves into the unique characteristics of Mesenchymal stem/stromal cells (MSCs) and their secreted exosomes, which notably exhibit immunomodulatory and regenerative properties. By comprehensively assessing the current literature and ongoing research in this field, this review sheds light on the plausible mechanisms by which MSCs and their exosomes can be harnessed to selectively target fungal persisters. Additionally, prospective approaches in the use of cell-based therapeutic modalities are examined, emphasizing the importance of further research to overcome the enigmatic fungal persistence.

Ligustrazine inhibits inflammatory response of human endometrial stromal cells through the STAT3/IGF2BP1/RELA axis

CONTEXT

Endometriosis (EMs) is a gynecological disorder. Ligustrazine has been reported to exert an anti-inflammatory effect on EMs. However, the underlying mechanisms are not completely understood.

OBJECTIVE

To investigate the effects of ligustrazine on the progression of EMs and the underlying regulatory mechanisms.

MATERIALS AND METHODS

Human endometrial stromal cells (HESCs) were isolated from patients with EMs or control subjects. HESCs were treated with 25, 50, 100, or 200 μM ligustrazine for 1, 3, 6, or 12 h. Western blot and enzyme-linked immunosorbent assays were performed to determine the levels of proteins and inflammatory cytokines, respectively. The binding between STAT3 and insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was assessed by chromatin immunoprecipitation and dual-luciferase reporter assays. The relationship between IGF2BP1 and RELA was assessed by RNA immunoprecipitation and RNA pull-down assay.

RESULTS

Phosphorylated STAT3, IGF2BP1, RELA, TNF-α, IL-6, and IL-1β were upregulated in EMs tissues compared with control tissues (by 1.79-, 2.55-, 1.58-, 3.01-, 2.55-, and 3.34-fold, respectively). Ligustrazine inhibited the expression of p-STAT3, IGF2BP1, RELA, IL-6, TNF-α, and IL-1β. Overexpression of STAT3 promoted RELA-mediated inflammatory responses, while ligustrazine (100 µM) notably reversed this phenomenon. Ligustrazine also alleviated RELA-induced inflammation via downregulating IGF2BP1. STAT3 bound to the promoter of IGF2BP1, and IGF2BP1 bound to the RELA mRNA.

DISCUSSION AND CONCLUSION

Ligustrazine inhibited inflammation in EMs via regulating the STAT3/IGF2BP1/RELA axis. These findings propose a new agent against EMs and support the development of ligustrazine-based treatment strategies for EMs.