The unique structural and functional features of CXCL12

CXCL12+ fibroblastic reticular cells in lymph nodes facilitate immune tolerance by regulating T cell-mediated alloimmunity

Fibroblastic reticular cells (FRCs) are the master regulators of the lymph node (LN) microenvironment. However, the role of specific FRC subsets in controlling alloimmune responses remains to be studied. Single-cell RNA sequencing (scRNA-Seq) of naive and draining LNs (DLNs) of heart-transplanted mice and human LNs revealed a specific subset of CXCL12hi FRCs that expressed high levels of lymphotoxin-β receptor (LTβR) and are enriched in the expression of immunoregulatory genes. CXCL12hi FRCs had high expression of CCL19, CCL21, indoleamine 2,3-dioxygenase (IDO), IL-10, and TGF-β1. Adoptive transfer of ex vivo-expanded FRCs resulted in their homing to LNs and induced immunosuppressive environments in DLNs to promote heart allograft acceptance. Genetic deletion of LTβR and Cxcl12 in FRCs increased alloreactivity, abrogating the effect of costimulatory blockade in prolonging heart allograft survival. As compared with WT recipients, CXCL12+ FRC-deficient recipients exhibited increased differentiation of CD4+ T cells into Th1 cells. Nano delivery of CXCL12 to DLNs improved allograft survival in heart-transplanted mice. Our study highlights the importance of DLN CXCL12hi FRCs in promoting transplant tolerance.

Albiflorin inhibits inflammation to improve liver fibrosis by targeting the CXCL12/CXCR4 axis in mice

Liver fibrosis is a common pathological feature of chronic hepatic injury that currently lacks effective therapeutic interventions. Albiflorin (ALB), a pinane-type monoterpene derived from Paeonia lactiflora Pall, has notable anti-inflammatory and hepatoprotective effects. However, the potential role of ALB against liver fibrosis is largely unknown. In this study, we discovered that ALB significantly inhibited CCl4-induced liver fibrosis in mice. This was evidenced by improvements in liver and kidney function indexes, fibrosis indicators, and histopathological findings. In vitro studies also showed that ALB inhibited TGF-β1-induced LX-2 cell activation and reduced the expression of α-SMA and collagen I. Additionally, we found that ALB mitigates inflammation and ameliorates liver fibrosis by targeting the CXCL12/CXCR4 axis, as confirmed using the CXCR4 inhibitor AMD3100 in CCl4-treated mice. Notably, combining ALB with metformin (MET) enhanced the inhibition of liver fibrosis progression. These findings highlight that ALB exerts anti-liver fibrosis effects by targeting the CXCL12/CXCR4 axis, underscoring its potential as a standalone treatment or as an adjuvant therapy.

Proteomics suggests the role of Cxcl12 secreted by hucMSCs in the treatment of lipopolysaccharide-acute lung injury

Acute respiratory distress syndrome (ARDS) is a clinical syndrome characterized by a high mortality rate, and its treatment is relatively straightforward. The application of human umbilical cord mesenchymal stem cells (hucMSCs) for the treatment of ARDS has emerged as a novel therapeutic approach and has been the subject of extensive research. In this study, a mouse model of acute lung injury (ALI) was established, and hucMSCs were administered via tail vein injection to investigate the pathogenesis of ARDS and the protein alterations following hucMSC treatment. Data-independent acquisition (DIA) was employed for the proteomic analysis of lung tissue, which included the identification of differentially expressed proteins (DEPs) and their associated pathways. The relevant DEPs identified in the lung tissues of the three groups of mice included Arid5a, Mrpl4, Cxcl12, and Rnf121 (P <0.05). Silencing the expression of Cxcl12 in hucMSCs could significantly inhibit the therapeutic effect of hucMSCs in reducing the permeability of lung tissue and endothelial cells (P < 0.05). Additionally, the signaling pathways associated with the relevant DEPs were analyzed. The DEPs and the enriched pathways discussed herein provide valuable insights into the pathogenesis of ARDS and the potential applications of hucMSCs.

Transcriptome associated with single-cell analysis reveal the role of S-palmitoylation in coronary artery disease

Coronary artery disease (CAD), a widespread cardiovascular ailment, exhibits a strong association with palmitoylation. This research aimed to elucidate the role of S-palmitoylation in CAD through bioinformatics, providing novel perspectives on the mechanism underlying CAD. By intersecting differentially expressed genes with weighted gene co-expression network analysis (WGCNA) from the GSE113079 dataset, 534 differentially expressed palmitoylation-related genes (DE-PRGs) were identified. Protein-protein interaction (PPI) network analysis, in conjunction with machine learning algorithms and immune infiltration analysis utilizing CIBERSORT, identified CXCL12, KRTAP4-7, and PPP2R2B as pivotal hub genes in CAD progression with significant immune links. Enrichment analyses revealed their predominant roles in immune regulation. Nomogram and ROC curve analyses revealed robust diagnostic predictive capabilities grounded in the three hub genes. A regulatory network involving the transcription factor HDAC2 and miRNA hsa-mir-23a-3p was predicted. Single-cell sequencing (GSE121893) further highlighted endothelial cells, fibroblasts, and macrophages as central cellular interactors, with significant crosstalk among these populations. These findings positioned CXCL12, KRTAP4-7 and PPP2R2B as key palmitoylated hub genes in CAD, thereby offering dual potential as diagnostic markers and therapeutic targets.

Stromal Cell Subsets Show Model-Dependent Changes in Experimental Colitis and Affect Epithelial Tissue Repair and Immune Cell Activation

BACKGROUND

Previous work on inflammatory bowel disease (IBD) revealed changes in the abundance of colonic stromal subsets during intestinal inflammation. However, it is currently unknown whether these stromal cell subset changes are also reflected in different IBD mouse models and how commonly used IBD therapies affect stromal cell subset composition.

METHODS

Stromal subset markers CD55, C-X-C motif chemokine 12 (CXCL12), podoplanin (PDPN), CD90, and CD73 were analyzed by flow cytometry in 3 mouse models for IBD, namely interleukin (IL)-10 knockout (KO), dextran sulfate sodium-induced, and T-cell transfer model for colitis. Next, the effects of IBD therapies on the stromal subset composition were studied. In vitro experiments were performed to study the interaction between stromal cell subsets and epithelial/immune cells.

RESULTS

The colitis-induced changes in the abundance of stromal cell subsets differed considerably between the 3 colitis mouse models. Interestingly, treatment with IBD medication affected specific stromal subsets in a therapy and model-specific manner. In vitro experiments showed that specific stromal subsets affected epithelial wound healing and/or T-cell activation.

CONCLUSIONS

The relative abundance changes of stromal cell subsets during experimental colitis differ between 3 established colitis models. Treatment with IBD therapies influences stromal subset abundance, indicating their importance in IBD pathogenesis, possibly through affecting epithelial migration, and T-cell activation.

Development of chemokine network inhibitors using combinatorial saturation mutagenesis

Targeting chemokine-driven inflammation has been elusive due to redundant pathways constituting chemokine-immune cell networks. Tick evasins overcome redundant pathways by broadly targeting either CC or CXC-chemokine classes. Recently identified evasin-derived peptides inhibiting both chemokine classes provide a starting point for developing agents with enhanced potency and breadth of action. Structure-guided and affinity maturation approaches to achieve this are unsuitable when multiple targets are concerned. Here we develop a combinatorial saturation mutagenesis optimisation strategy (CoSMOS). This identifies a combinatorially mutated evasin-derived peptide with significantly enhanced pIC50 against three different inflammatory disease chemokine pools. Using AlphaFold 3 to model peptide - chemokine interactions, we show that the combinatorially mutated peptide has increased total and hydrophobic inter-chain bonding via tryptophan residues and is predicted to sterically hinder chemokine interactions required for immune cell migration. We suggest that CoSMOS-generated promiscuous binding activities could target disease networks where structurally related proteins drive redundant signalling pathways.

Transcriptomic Alterations Induced by Tetrahydrocannabinol in SIV/HIV Infection: A Systematic Review

Given the high prevalence of cannabis use among people with HIV (PWH) and its potential to modulate immune responses and reduce inflammation, this systematic review examines preclinical evidence on how tetrahydrocannabinol (THC), a key compound in cannabis, affects gene and micro-RNA expression in simian immunodeficiency virus (SIV)-infected macaques and HIV-infected human cells. Through a comprehensive search, 19 studies were identified, primarily involving SIV-infected macaques, with a pooled sample size of 176, though methodological quality varied across the studies. Pathway analysis of differentially expressed genes (DEGs) and miRNAs associated with THC revealed enrichment in pathways related to inflammation, epithelial cell proliferation, and adhesion. Notably, some DEGs were targets of the differentially expressed miRNAs, suggesting that epigenetic regulation may contribute to THC's effects on gene function. These findings indicate that THC may help mitigate chronic immune activation in HIV infection by altering gene and miRNA expression, suggesting its potential immunomodulatory role. However, the evidence is constrained by small sample sizes and inconsistencies across studies. Further research employing advanced methodologies and larger cohorts is essential to confirm THC's potential as a complementary therapy for PWH and fully elucidate the underlying mechanisms, which could inform targeted interventions to harness its immunomodulatory effects.

Transfusion-Related Acute Lung Injury: from Mechanistic Insights to Therapeutic Strategies

Transfusion-related acute lung injury (TRALI) is a potentially lethal complication of blood transfusions, characterized by the rapid onset of pulmonary edema and hypoxemia within six hours post-transfusion. As one of the primary causes of transfusion-related mortality, TRALI carries a significant mortality rate of 6-12%. However, effective treatment strategies for TRALI are currently lacking, underscoring the urgent need for a comprehensive and in-depth understanding of its pathogenesis. This comprehensive review provides an updated and detailed analysis of the current landscape of TRALI, including its clinical presentation, pathogenetic hypotheses, animal models, cellular mechanisms, signaling pathways, and potential therapeutic targets. By highlighting the critical roles of these pathways and therapies, this review offers valuable insights to inform the development of preventative and therapeutic strategies and to guide future research efforts aimed at addressing this life-threatening condition.

Decoding the immune Response: Analyzing PBMCs in ischemic stroke and Evaluating the effects of Rivaroxaban on gene expression

BACKGROUND

Ischemic stroke (IS) is primarily caused by intricate inflammatory pathways and is a major global reason for mortality and disability. Patients with atrial fibrillation are treated with Rivaroxaban, a direct factor Xa inhibitor, to avoid stroke. This study looks at how certain genes are expressed in individuals with IS and how Rivaroxaban affects these genes and proteins.

METHODS

Using gene expression data from the GEO database, dysregulated genes in IS patients were found. Peripheral blood mononuclear cells from 50 IS patients were used to measure the expression of CXCL8, CXCL2, and G0S2 90 days before and after Rivaroxaban therapy using RT-PCR and ELISA. The Enrichr online tool was used to perform a functional enrichment analysis.

RESULTS

GEO2R analysis revealed that CXCL8, CXCL2, and G0S2 were significantly upregulated in IS samples compared to controls. Following Rivaroxaban therapy, the mRNA and protein levels of these genes showed a marked reduction, indicating a potential anti-inflammatory effect.

CONCLUSION

Rivaroxaban may control inflammatory responses in patients with IS, according to the study, which also reveals important genes implicated in IS. These results demonstrate the possibility of focused treatment approaches to reduce inflammation brought on by stroke.

Transcriptomic signatures of cold acclimated adipocytes reveal CXCL12 as a Brown autocrine and paracrine chemokine

Besides its thermogenic capacity, brown adipose tissue (BAT) performs important secretory functions that regulate metabolism. However, the BAT microenvironment and factors involved in BAT homeostasis and adaptation to cold remain poorly characterized. We therefore aimed to study brown adipocyte-derived secreted factors that may be involved in adipocyte function and/or may orchestrate intercellular communications. For this, mRNA levels in mature adipocytes from mouse adipose depots were assessed using RNA sequencing upon chronic cold acclimation, and bioinformatic analysis was used to identify secreted factors. Among 858 cold-sensitive transcripts in BAT adipocytes were 210 secreted factor-encoding genes, and Cxcl12 was the top brown adipocyte-enriched cytokine. Cxcl12 mRNA expression analysis by RT-qPCR and fluorescence in situ hybridization specified Cxcl12 distribution in various cell types, and indicated its enrichment in cold-acclimated brown adipocytes. We found that CXCL12 secretion from BAT was increased after chronic cold, yet its level in plasma remained unchanged, suggesting a local/paracrine function. Cxcl12 knockdown in mature brown adipocytes impaired thermogenesis, as assessed by norepinephrine (NE)-induced glycerol release and mitochondrial respiration. However, knockdown of Cxcl12 did not impact β-adrenergic signaling, suggesting that CXCL12 regulates adipocyte function downstream of the β-adrenergic pathway. Moreover, we provide evidence for CXCL12 to exert intercellular cross-talk via its capacity to promote macrophage chemotaxis and neurite outgrowth. Collectively, our results indicate that CXCL12 is a brown adipocyte-enriched, cold-induced secreted factor involved in adipocyte function and the BAT microenvironment communication network.

PerC B-Cells Activation via Thermogenetics-Based CXCL12 Generator for Intraperitoneal Immunity Against Metastatic Disseminated Tumor Cells

During cancer peritoneal metastasis (PM), conventional antigen-presenting cells (dendritic cells, macrophages) promote tumorigenesis and immunosuppression in peritoneal cavity. While intraperitoneal immunotherapy (IPIT) has been used in clinical investigations to relieve PM, the limited knowledge of peritoneal immunocytes has hindered the development of therapeutic IPIT. Here, a dendritic cell-independent, next-generation IPIT is described that activates peritoneal cavity B (PerC B) cell subsets for intraperitoneal anti-tumor immunity via exogenous antigen presentation. The PerC B-cell-involved IPIT framework consists of an isotropic-porous, cell-fitting, thermogenetics-based CXCL12 generator. Such nanoscale thermal-confined generator can programmatically fine-tune the expression of CXCL12 to recruit disseminated tumor cells (DTCs) through CXCL12-CXCR4 axis while avoiding cytokine storm, subsequently release DTC-derived antigen to trigger PerC B-cell-involved immunity. Notably, antigen-presenting B-cell cluster, expressing the regulatory signaling molecules Ptpn6, Ms4a1, and Cd52, is identified playing the key role in the IPIT via single-cell RNA sequencing. Moreover, such IPIT availably assuages peritoneal effusion and PM in an orthotopic gastric cancer and metastatic model. Overall, this work offers a perspective on PerC B-cell-involved antigen-presenting in intraperitoneal immunity and provides a configurable strategy for activating anti-DTC immunity for next-generation IPIT.

Diphlorethohydroxycarmalol inhibits Müller cell gliosis by disrupting CXCR4/CXCL12 interaction in violet-blue light-induced retinal phototoxicity

Müller gliosis is a complex process that impairs the ability of retinal Müller glial cells to respond to various forms of retinal injury or disease, leading to retinal damage. Blue light (BL) exposure is a known cause of retinal damage. In this study, we aimed to investigate the potential of DPHC in inhibiting Müller gliosis in models of BL-exposure. We conducted in silico binding analysis to evaluate the binding of DPHC to CXCR4. Then, we developed in vitro and in vivo experimental models to assess the effects of DPHC and BL exposure on Müller gliosis using MIO-M1 cells and zebrafish. Our findings show that DPHC can suppress the Müller gliosis process in BL-exposed MIO-M1 cells in vitro and in BL-exposed zebrafish in vivo. In silico molecular docking, we identified CXCR4 as the target of active site 1 of DPHC. In BL-exposed MIO-M1 cells, DPHC inhibited CXCR4 activity and altered the expression of Müller gliosis markers and NF-κB-related ERK and AKT signaling. In BL-exposed zebrafish, DPHC prevented retinal thickness reduction and inhibited CXCR4 expression and retinal cell apoptosis. This study suggests that DPHC could be a potential therapeutic agent for retinal diseases involving Müller gliosis. By inhibiting CXCR4 activity, DPHC downregulates the ERK/AKT/NF-κB pathway, reducing retinal cell apoptosis and altered expression of Müller gliosis markers. These findings highlight the potential of natural bioactive compounds for treating various diseases, and further research should investigate the therapeutic potential of DPHC and its derivatives.

Skeletal Stem Cells: A Basis for Orthopaedic Pathology and Tissue Repair

➢ Skeletal stem cells (SSCs) continually replenish mature cell populations to support skeletal homeostasis.➢ SSCs repopulate by self-renewal, have multilineage potential, and are long-lived in vivo.➢ SSCs express specific combinations of cell surface markers that reflect their lineage identity.➢ SSCs adapt to their anatomic environment to support regional differences in skeletal behavior and pathology.

BMSCs Downregulate CXCL12 by Secreting Exosomal miR-20a-5p to Promote Macrophage M2 Polarization and Alleviate the Development of Sepsis

OBJECTIVE

Sepsis is a syndrome of the systemic inflammatory response caused by infection that can endanger a patient's life. The aim of this study was to explore the molecular mechanism by which bone marrow mesenchymal stem cells-derived exosomes (BMSCs-exo) carrying miR-20a-5p regulate the progression of sepsis.

METHODS

Clinical samples from sepsis patients were collected. Mouse and cell models of sepsis were induced by lipopolysaccharide (LPS). The levels of related genes and proteins were determined by RT‒qPCR, Western blotting and ELISA. CCK-8 and flow cytometry assays were used to assess cell viability, apoptosis, and markers of macrophage polarization.

RESULTS

In septic patients, miR-20a-5p levels were significantly lower and CXCL12 expression was significantly increased. After LPS induction, M2 polarization of macrophages was significantly reduced, the level of inflammatory factors was increased, and apoptosis was increased. The addition of BMSCs-exo increased the miR-20a-5p level and decreased the expression of CXCL12 in macrophages, thereby promoting macrophage M2 polarization and reducing the levels of inflammatory factors.

CONCLUSION

This study demonstrated for the first time that BMSCs-exo promoted the polarization of M2 macrophages through the miR-20a-5p/CXCL12 axis, thus alleviating the development of sepsis. These findings provide a new theoretical basis for the targeted treatment of sepsis with exosomes or miR-20a-5p.

Nanodevice-Mediated Immune Cell Recruitment: Targeting Senescent Cells via MMP-3-Responsive CXCL12-Coated Nanoparticles

Senescent cells are involved in age-related disorders in different organs and are therapeutic targets for fibrotic and chronic pathologies. Immune-modulating agents, able to enhance senescent cell detection and elimination by endogenous immune cells, have emerged as pharmacological strategies. We report herein a nanoparticle for immune cell-mediated senolytic therapy designed to recruit immune cells in response to specific enzymatic matrix metalloproteinase-3 (MMP-3) activity in the senescence-associated secretory phenotype. For this, mesoporous silica nanoparticles (MSNs) are coated with a peptide substrate of the metalloproteinase MMP-3, and the peptide is decorated with chemokine CXCL12 that enhances immune cell recruitment (NPs@CXCL12). Controlled release studies confirmed the progressive and specific release of CXCL12 in the presence of MMP-3. The ability of immune cell recruitment in response to a senescent microenvironment (senescent WI-38 fibroblasts) is confirmed by Transwell migration assays with green fluorescent Jurkat T-cells, showing NPs@CXCL12 has an enhanced chemotaxis effect toward senescent cells compared to free CXCL12 (2-fold). Moreover, the cytotoxic capacity of human primary natural killer (NK) cells over senescent WI-38 is also confirmed, and their migration trajectories in response to NPs@CXCL12 or free CXCL12 are monitored by using a microfluidic device. Results confirm the ability of NPs@CXCL12 to generate a chemotactic gradient able to attract NK cells. When compared with free CXCL12, the NPs@CXCL12 system showed a reduction of up to 15.56% in the population of NK cells migrating toward free CXCL12 under competitive conditions. This study demonstrates the potential of designing nanoparticles to recruit immune cells under specific responses to eliminate senescent cells. Results confirm that NPs@CXCL12 can effectively establish a chemotactic gradient to attract NK cells.

Computational Identification of Migrating T cells in Spatial Transcriptomics Data

T cells are the central players in antitumor immunity, and effective tumor killing depends on their ability to infiltrate into the tumor microenvironment (TME) while maintaining normal cytotoxicity. However, late-stage tumors develop immunosuppressive mechanisms that impede T cell movement and induce exhaustion. Investigating T cell migration in human tumors in vivo could provide novel insights into tumor immune escape, although it remains a challenging task. In this study, we developed ReMiTT, a computational method that leverages spatial transcriptomics data to track T cell migration patterns within tumor tissue. Applying ReMiTT to multiple tumor samples, we identified potential migration trails. On these trails, chemokines that promote T-cell trafficking display an increasing trend. Additionally, we identified key genes and pathways enriched on these migration trails, including those involved in cytoskeleton rearrangement, leukocyte chemotaxis, cell adhesion, leukocyte migration, and extracellular matrix (ECM) remodeling. Furthermore, we characterized the phenotypes of T cells along these trails, showing that the migrating T cells are highly proliferative. Our findings introduce a novel approach for studying T cell migration and interactions within the tumor microenvironment (TME), offering valuable insights into tumor-immune dynamics.

CXCL12 is a potential therapeutic target for type 2 diabetes mellitus complicated by chronic obstructive pulmonary disease

OBJECTIVES

To identify the key genes and immunological pathways shared by type 2 diabetes mellitus (T2DM) and chronic obstructive pulmonary disease (COPD) and explore the potential therapeutic targets of T2DM complicated by COPD.

METHODS

GEO database was used for analyzing the gene expression profiles in T2DM and COPD to identify the common differentially expressed genes (DEGs) in the two diseases. A protein-protein interaction network was constructed to identify the candidate hub genes, which were validated in datasets and disease sets to obtain the target genes. The diagnostic accuracy of these target genes was assessed with ROC analysis, and their expression levels and association with pulmonary functions were investigated using clinical data and blood samples of patients with T2DM and COPD. The abundance of 22 immune cells was analyzed with CIBERSORT algorithm, and their relationship with the target genes was examined using correlation analysis. DGIdb database was used for analyzing the drug-gene interactions and the druggable genes followed by gene set enrichment analysis.

RESULTS

We identified a total of 175 common DEGs in T2DM and COPD, mainly enriched in immune- and inflammation-related pathways. Among these genes, CXCL12 was identified as the final target gene, whose expression was elevated in both T2DM and COPD (P<0.05) and showed good diagnostic efficacy. Immune cell infiltration correlation analysis showed significant correlations of CXCL12 with various immune cells (P<0.01). GESA analysis showed that high CXCL12 expression was significantly correlated with "cytokine-cytokine receptor interaction". Drug-gene analysis showed that most of CXCL12-related drugs were not targeted drugs with significant cytotoxicity.

CONCLUSIONS

CXCL12 is a potential common key pathogenic gene of COPD and T2DM, and small-molecule targeted drugs against CXCL12 can provide a new strategy for treatment T2DM complicated by COPD.

Association of dipeptidyl peptidase-4 with Alzheimer's disease: A new therapeutic prospect

Alzheimer's disease (AD) is the most common disease associated with cognitive dysfunction, which is closely associated with type 2 diabetes mellitus (T2DM) in clinical manifestations, pathological changes and prevention. Inhibition of dipeptidyl peptidase 4 (DPP-4) can lower blood glucose levels by stimulating insulin secretion. Besides, it can affect cognitive function through the neuroprotective effect of DPP-4 substrates, such as glucose-dependent insulin peptide and glucagon-like peptide-1, the proteolytic effect on amyloid-β and the protective effect on neuronal structure. This review discusses the relationship between cognitive impairment in T2DM and in AD, summarizes the effect of DPP-4 inhibitor (DPP-4i) on improving cognitive impairment in these two diseases based on the current studies. Given the lack of clinical randomized trials that evaluate the effect of DPP-4i on AD, this review is expected to provide preclinical evidence for DPP-4i as a potential therapy for the treatment and prevention of AD.

C-X-C Motif Chemokine 12 Was Identified as a Potential Gene Target in the Treatment of Crohn's Disease

Object

The present study aimed to identify hub genes associated with the treatment and control of active and inactive Crohn's disease (CD).

Methods

Differentially expressed genes (DEGs) were identified in normal, active CD, and inactive CD samples from GSE95095 dataset. Intersection genes screened by Venn diagram in DEGs. Subsequently, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were conducted on the intersection genes. The protein-protein interaction (PPI) network was used to screen of hub gene. The expression and mRNA levels of CXCL12 in CD and ROC curves in GSE95095 dataset. Signaling pathways of hub genes and their correlation with immune cells were analyzed by gene set enrichment analysis (GSEA), EPIC, and ESTIMATE, respectively. Finally, immunohistochemistry (IHC) and Reverse Transcription-Polymerase Chain Reaction (RT-PCR) were used to detect the expression of the hub gene in normal, inactive, and active CD tissues.

Results

In GSE95095 dataset, CXCL12 was identified as the most hub gene by limma analysis, Venn diagram and A protein-protein interaction (PPI) network. CXCL12 expression was highest in active CD (p < 0.001) followed by inactive CD (p < 0.01). Subsequently, it was validated through IHC and RT-PCR in normal intestinal mucosal, active CD, and inactive CD. CXCL12 was overexpressed in active and inactive CD (IHC: p < 0.001 and RT-PCR: p < 0.001, respectively). CXCL12 expression in active CD was determined via analysis with receiver operating characteristic (ROC) curves. The specificity and sensitivity were 0.875 and 0.625, respectively, the accuracy was 72.92%, the area under the curve (AUC) was 0.780, and the 95% confidence interval (CI) was in the range of 0.648-0.912. CXCL12 expression was closely correlated with various immune cells.

Conclusion

CXCL12 is overexpressed in active CD and is closely correlated with various immune cells. We propose that CXCL12 as a potential target genes for the treatment and management of both active and inactive CD.

Exploring G Protein-Coupled Receptors in Hematological Cancers

Hematological cancers, such as lymphomas and leukemias, pose significant challenges in oncology, necessitating a deeper understanding of their molecular landscape to enhance therapeutic strategies. This article critically examines and discusses recent research on the roles of G protein-coupled receptors (GPCRs) in myeloma, lymphomas, and leukemias with a particular focus on pediatric acute lymphoblastic (lymphocytic) leukemia (ALL). By utilizing RNA sequencing (RNA-seq), we analyzed GPCR expression patterns in pediatric ALL samples (aged 3-12 years old), with a further focus on Class A orphan GPCRs. Our analysis revealed distinct GPCR expression profiles in pediatric ALL, identifying several candidates with aberrant upregulated expression compared with healthy counterparts. Among these GPCRs, GPR85, GPR65, and GPR183 have varying numbers of studies in the field of hematological cancers and pediatric ALL. Furthermore, we explored missense mutations of pediatric ALL in relation to the RNA gene expression findings, providing insights into the genetic underpinnings of this disease. By integrating both RNA-seq and missense mutation data, this article aims to provide an insightful and broader perspective on the potential correlations between specific GPCR and their roles in pediatric ALL.

Natural lung-tropic TH9 cells: a sharp weapon for established lung metastases

BACKGROUND

Lung metastasis remains the primary cause of tumor-related mortality, with limited treatment options and unsatisfactory efficacy. In preclinical studies, T helper 9 (TH9) cells have shown promise in treating solid tumors. However, it is unclear whether TH9 cells can tackle more challenging situations, such as established lung metastases. Moreover, comprehensive exploration into the nuanced biological attributes of TH9 cells is imperative to further unravel their therapeutic potential.

METHODS

We adoptively transferred TH1, TH9, and TH17 cells into subcutaneous, in situ, and established lung metastases models of osteosarcoma and triple-negative breast cancer, respectively, comparing their therapeutic efficacy within each distinct model. We employed flow cytometry and an in vivo imaging system to evaluate the accumulation patterns of TH1, TH9, and TH17 cells in the lungs after transfusion. We conducted bulk RNA sequencing on in vitro differentiated TH9 cells to elucidate the chemokine receptor CXCR4, which governs their heightened pulmonary tropism relative to TH1 and TH17 cell counterparts. Using Cd4 cre Cxcr4 flox/flox mice, we investigate the effects of CXCR4 on the lung tropism of TH9 cells. We performed mass spectrometry to identify the E3 ligase responsible for CXCR4 ubiquitination and elucidated the mechanism governing CXCR4 expression within TH9 cellular milieu. Ultimately, we analyzed the tumor immune composition after TH9 cell transfusion and evaluated the therapeutic efficacy of adjunctive anti-programmed cell death protein-1 (PD-1) therapy in conjunction with TH9 cells.

RESULTS

In this study, we provide evidence that TH9 cells exhibit higher lung tropism than TH1 and TH17 cells, thereby exhibiting exceptional efficacy in combating established lung metastases. CXCR4-CXCL12 axis is responsible for lung tropism of TH9 cells as ablating CXCR4 in CD4+ T cells reverses their lung accumulation. Mechanistically, tumor necrosis factor receptor-associated factor 6 (TRAF6)-driven hyperactivation of NF-κB signaling in TH9 cells inhibited ITCH-mediated ubiquitination of CXCR4, resulting in increased CXCR4 accumulation and enhanced lung tropism of TH9 cells. Besides, TH9 cells' transfusion significantly improved the immunosuppressed microenvironment. TH9 cells and anti-PD-1 exhibit synergistic effects in tumor control.

CONCLUSIONS

Our findings emphasized the innate lung tropism of TH9 cells driven by the activation of TRAF6, which supports the potential of TH9 cells as a promising therapy for established lung metastases.

Co-expression network and survival analysis of breast cancer inflammation and immune system hallmark genes

The tertiary lymphoid structure (TLS) plays a central role in cancer immune response, and its gene expression pattern, called the TLS signature, has shown prognostic value in breast cancer. The formation of TLS and tumor-associated high endothelial venules (TA-HEVs), responsible for lymphocytic infiltration within the TLS, is associated with the expression of cancer hallmark genes (CHGs) related to immunity and inflammation. In this study, we performed co-expression network analysis of immune- and inflammation-related CHGs to identify predictive genes for breast cancer. In total, 382 immune- and inflammation-related CHGs with high expression variance were extracted from the GSE86166 microarray dataset of patients with breast cancer. CHGs were classified into five modules by applying weighted gene co-expression network analysis. The survival analysis results for each module showed that one module comprising 45 genes was statistically significant for relapse-free and overall survival. Four network properties identified key genes in this module with high prognostic prediction abilities: CD34, CXCL12, F2RL2, JAM2, PROS1, RAPGEF3, and SELP. The prognostic accuracy of the seven genes in breast cancer was synergistic and exceeded that of other predictors in both small and large public datasets. Enrichment analysis predicted that these genes had functions related to leukocyte infiltration of TA-HEVs. There was a positive correlation between key gene expression and the TLS signature, suggesting that gene expression levels are associated with TLS density. Co-expression network analysis of inflammation- and immune-related CHGs allowed us to identify genes that share a standard function in cancer immunity and have a high prognostic predictive value. This analytical approach may contribute to the identification of prognostic genes in TLS.

Carotid artery transplantation of brain endothelial cells enhances neuroprotection and neurorepair in ischaemic stroke rats

Brain microvascular endothelial cells (BMECs), an important component of the neurovascular unit, can promote angiogenesis and synaptic formation in ischaemic mice after brain parenchyma transplantation. Since the therapeutic efficacy of cell-based therapies depends on the extent of transplanted cell residence in the target tissue and cell migration ability, the delivery route has become a hot research topic. In this study, we investigated the effects of carotid artery transplantation of BMECs on neuronal injury, neurorepair, and neurological dysfunction in rats after cerebral ischaemic attack. Purified passage 1 endothelial cells (P1-BMECs) were prepared from mouse brain tissue. Adult rats were subjected to transient middle cerebral artery occlusion (MCAO) for 30 min. Then, the rats were treated with 5 × 105 P1-BMECs through carotid artery infusion or tail vein injection. We observed that carotid artery transplantation of BMECs produced more potent neuroprotective effects than caudal injection in MCAO rats, including reducing infarct size and alleviating neurological deficits in behavioural tests. Carotid artery-transplanted BMECs displayed a wider distribution in the ischaemic rat brain. Immunostaining for endothelial progenitor cells and the mature endothelial cell markers CD34 and RECA-1 showed that carotid artery transplantation of BMECs significantly increased angiogenesis. Carotid artery transplantation of BMECs significantly increased the number of surviving neurons, decreased the cerebral infarction volume, and alleviated neurological deficits. In addition, we found that carotid artery transplantation of BMECs significantly enhanced ischaemia-induced hippocampal neurogenesis, as measured by doublecortin (DCX) and Ki67 double staining within 2 weeks after ischaemic injury. We conclude that carotid artery transplantation of BMECs can promote cerebral angiogenesis, neurogenesis, and neurological function recovery in adult rats after ischaemic stroke. Our results suggest that carotid injection of BMECs may be a promising new approach for treating acute brain injuries.

Effects of bone metabolism on hematopoiesis: A Mendelian randomization study

Objectives

Osteoblast is known to regulate hematopoiesis according to preclinical studies but the causal relationship in human remains uncertain. We aimed to evaluate causal relationships of bone mineral density (BMD) with blood cell traits using genetic data.

Methods

Summary statistics from the largest available genome-wide association study were retrieved for total body BMD (TBBMD), lumbar spine BMD (LSBMD), femoral neck BMD (FNBMD) and 29 blood cell traits including red blood cell, white blood cell and platelet-related traits. Using two-sample Mendelian randomization (MR) approach, inverse-variance weighted method was adopted as main univariable MR analysis. Multivariable MR (MVMR) analysis was conducted to evaluate whether the casual effect is independent of confounders.

Results

BMD was positively associated with reticulocyte-related traits, including high light scatter reticulocyte count and percentage, immature reticulocyte fraction, reticulocyte count and percentage, with causal effect estimate (beta) ranging from 0.023 to 0.064. Conversely, inverse association of BMD with hematocrit, hemoglobin, and red blood cell count was observed, with beta ranging from -0.038 to -0.019. The association remained significant in MVMR analysis after adjustment for confounders. For white blood cells, BMD was inversely associated with neutrophil count (beta: 0.029 to -0.019) and white blood cell count (beta: 0.024 to -0.02). Results across TBBMD, LSBMD, and FNBMD were consistent.

Conclusions

This study suggested bone metabolism had a causal effect on hematopoietic system in humans. Its causal effect on red blood cell traits was independent of confounders. Further studies on how improving bone health can reduce risk of hematological disorders are warranted.

Increased serum EGF but not SDF-1 levels are associated with the pathophysiology and development of generalized anxiety disorder

Generalized anxiety disorder (GAD) is a common and persistent mental illness accompanied by uncontrollable worries for daily staff. Physiological, environmental, genetic, and daily stress from surroundings is involved in developing GAD. Here, we aimed to assess the association of stromal cell-derived factor-1 (SDF-1) and epidermal growth factor (EGF) in the pathophysiology of GAD and their role as diagnostic tools. This case-control study recruited 50 GAD patients from the psychiatry department of a tertiary care teaching hospital in Dhaka city and 38 age-sex-matched healthy controls (HCs) from the surrounding areas. A qualified psychiatrist conducted standardized psychiatric interview to diagnose GAD patients and evaluate HCs by applying the diagnostic and statistical manual for mental disorders, 5th edition (DSM-5) and used the GAD-7 scale to assess the severity of the GAD symptoms. After confirming the inclusion and exclusion criteria, we collected 5 ml blood samples from each participant. We measured serum SDF-1 and EGF levels using ELISA techniques. We observed increased serum levels of EGF in GAD patients compared to HCs (5.91 ± 3.90 ng/ml vs. 1.59 ± 1.08 ng/ml; p < 0.001). Also, this increment is positively associated with the severity of GAD in patients (r = 0.479, p = 0.002). The receiver operating characteristic analysis showed good diagnostic performance (AUC 0.869, p < 0.001) with high sensitivity (82.5%), and specificity (81.1%) at cut off value of 2.31 ng/ml. However, we didn't find significant differences in serum SDF-1 levels between GAD patients and HCs (11.96 ± 4.50 ng/ml vs. 12.70 ± 11.76 ng/ml; p = 0.337). The present study suggests that GAD patients have increased serum EGF levels but not SDF-1 levels compared to HCs and that increased EGF levels are associated with increased GAD symptoms as well. Moreover, EGF levels could serve as a biomarker for GAD However, further interventional studies with larger and homogeneous samples are suggested to confirm and establish these findings.

Culture Expansion Alters Human Bone Marrow-Derived Mesenchymal Stem Cell Production of Osteoarthritis-Relevant Cytokines and Growth Factors

PURPOSE

The purposes of this study were to characterize the human bone marrow-derived mesenchymal stem cells (BM-MSCs) production of osteoarthritis-relevant cytokines and growth factors as they are purified and multiplied, a process termed culture expansion, and to compare the immunomodulatory potential of BM-MSCs based on source and medium used for culture expansion.

METHODS

BM-MSCs were obtained from iliac crest bone marrow aspirates of 4 healthy donors. These 4 BM-MSC cell lines underwent 4 rounds, or "passages," of the institutional culture expansion protocol, using institutional culture media. The secretory molecules known to play a role in osteoarthritis-related inflammatory immune response, cartilage degradation, and patient symptoms, together called the BM-MSC "secretome," were measured at each passage. Three lines of commercially available BM-MSCs from healthy donors underwent culture expansion by the same protocol, using commercial culture media. The commercial BM-MSCs secretome and the institutional BM-MSCs secretome were compared at each passage. Significance was set at P < .05.

RESULTS

Institutional BM-MSCs produced less interleukin-6 at passages 3 (237 ± 113 pg/mL) and 4 (237 ± 113 pg/mL) compared with passages 1 (884 ± 97 pg/mL) and 2 (1071 ± 129 pg/mL; P < .01). Institutional BM-MSCs produced more macrophage inflammatory protein 3-alpha at passage 4 than at passage 1 (106 ± 41 vs 32 ± 7 pg/mL; P < .01). Across passages of culture expansion, institutional BM-MSCs grown on institutional medium expressed more interleukin-6 (P < .001), interleukin-10 (P < .001), interleukin-1 beta (P < .001), tumor necrosis factor alpha (P = .004), and vascular endothelial growth factor C (P = .003) than commercially available BM-MSCs grown on commercial medium.

CONCLUSIONS

Culture expansion alters key molecules within the BM-MSC secretome. Additionally, differences in BM-MSC source and culture medium alter the BM-MSC secretome and its immunomodulatory potential.

CLINICAL RELEVANCE

This study characterizes the in-vitro changes in BM-MSC secretome during culture expansion based on the cell source and culture medium. It suggests nonequivalence of culture-expanded BM-MSC therapies obtained from different donors using different culture media, even if delivering equivalent numbers of BM-MSCs.

Research Advances in Adenomyosis-Related Signaling Pathways and Promising Targets

Adenomyosis is a benign gynecological condition characterized by the proliferation of the endometrial stroma and glands into the myometrium, uterine volume enlargement, and peripheral smooth muscle hypertrophy. The typical clinical symptoms include chronic pelvic pain, abnormal uterine bleeding, and subfertility, all of which significantly impact quality of life. There are no effective prevention or treatment strategies for adenomyosis, partly due to a limited understanding of the pathological mechanisms underlying the initiation and progression of the disease. Given that signaling pathways play a crucial role in the development of adenomyosis, a better understanding of these signaling pathways is essential for identifying therapeutic targets and advancing drug development. The occurrence and progression of adenomyosis are closely linked to various underlying pathophysiological mechanisms, including proliferation, migration, invasion, fibrosis, angiogenesis, inflammation, oxidative stress, immune response, and epigenetic changes. This review summarizes the signaling pathways and targets associated with the pathogenesis of adenomyosis, including CXCL/CXCR, NLRP3, NF-κB, TGF-β/smad, VEGF, Hippo/YAP, PI3K/Akt/mTOR, JAK/STAT, and other relevant pathways. In addition, it identifies promising future targets for the development of adenomyosis treatment, such as m6A, GSK3β, sphks, etc.

Post-stroke hippocampal neurogenesis is impaired by microvascular dysfunction and PI3K signaling in cerebral amyloid angiopathy

Ischemic stroke and cerebral amyloid angiopathy (CAA) pose significant challenges in an aging population, particularly in post-stroke recovery. Using the 5xFAD mouse model, we explore the relationship between CAA, ischemic stroke, and tissue recovery. We hypothesize that amyloid-beta accumulation worsens stroke outcomes by inducing blood-brain barrier (BBB) dysfunction, leading to impaired neurogenesis. Our findings show that CAA exacerbates stroke outcomes, with mice exhibiting constricted BBB microvessels, reduced cerebral blood flow, and impaired tissue recovery. Transcriptional analysis shows that endothelial cells and neural progenitor cells (NPCs) in the hippocampus exhibit differential gene expression in response to CAA and stroke, specifically targeting the phosphatidylinositol 3-kinase (PI3K) pathway. In vitro experiments with human NPCs validate these findings, showing that disruption of the CXCL12-PIK3C2A-CREB3L2 axis impairs neurogenesis. Notably, PI3K pathway activation restores neurogenesis, highlighting a potential therapeutic approach. These results suggest that CAA combined with stroke induces microvascular dysfunction and aberrant neurogenesis through this specific pathway.

A Dual-Function LipoAraN-E5 Coloaded with N4-Myristyloxycarbonyl-1-β-d-arabinofuranosylcytosine (AraN) and a CXCR4 Antagonistic Peptide (E5) for Blocking the Dissemination of Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a hematological malignancy with a high recurrence rate. The interaction of chemokine receptor 4/chemokine ligand 12 (CXCR4/CXCL12) mediates homing and adhesion of AML cells in bone marrow, leading to minimal residual disease in patients, which brings a hidden danger for future AML recurrence. Ara-C is a nonselective chemotherapeutic agent against AML. Due to its short half-life and severe side effects, a lipid-like Ara-C derivative (AraN) was synthesized and a dual-function LipoAraN-E5 (135 nm, encapsulation efficiency 99%) was developed, which coloaded AraN and E5, a peptide of the CXCR4 antagonist. LipoAraN-E5 effectively improved the uptake, enhanced the inhibition of leukemia cell proliferation, migration, and adhesion to stromal cells in bone marrow, and mobilized the leukemia cells from bone marrow to peripheral blood via interfering with the CXCR4/CXCL12 axis. LipoAraN-E5 prolonged the plasma half-life of AraN (8.31 vs 0.56 h) and was highly enriched in peripheral blood (3.67 vs 0.05 μmol/g at 8 h) and bone marrow (379 vs 148 μmol/g at 24 h). LipoAraN-E5 effectively prevented the infiltration of leukemia cells in peripheral blood, bone marrow, spleen, and liver, prolonged the mice survival, and showed outstanding antineoplastic efficacy with negligible toxicity, which were attributed to the ingenious design of AraN, the use of a liposomal delivery carrier, and the introduction of E5. Our work revealed that LipoAraN-E5 may be a promising nanocandidate against AML.

Human pancreatic islet-derived stromal cells reveal combined features of mesenchymal stromal cells and pancreatic stellate cells

BACKGROUND

Mesenchymal stromal cells (MSCs) are recognized for their potential in regenerative medicine, attributed to their multipotent differentiation capabilities and immunomodulatory properties. Despite this potential, the classification and detailed characterization of MSCs, especially those derived from specific tissues like the pancreas, remains challenging leading to a proliferation of terminology in the literature. This study aims to address these challenges by providing a thorough characterization of human pancreatic islets-derived mesenchymal stromal cells (hPD-MSCs).

METHODS

hPD-MSCs were isolated from donor islets using enzymatic digestion, immortalized through lentiviral transduction of human telomerase reverse transcriptase (hTERT). Cells were characterized by immunostaining, flow cytometry and multilineage differentiation potential into adipogenic and osteogenic lineages. Further a transcriptomic analysis was done to compare the gene expression profiles of hPD-MSCs with other mesenchymal cells.

RESULTS

We show that hPD-MSCs express the classical MSC features, including morphological characteristics, surface markers expression (CD90, CD73, CD105, CD44, and CD106) and the ability to differentiate into both adipogenic and osteogenic lineages. Furthermore, transcriptomic analysis revealed distinct gene expression profiles, showing notable similarities between hPD-MSCs and pancreatic stellate cells (PSCs). The study also identified specific genes that distinguish hPD-MSCs from MSCs of other origins, including genes associated with pancreatic function (e.g., ISL1) and neural development (e.g., NPTX1, ZNF804A). A novel gene with an unknown function (ENSG00000286190) was also discovered.

CONCLUSIONS

This study enhances the understanding of hPD-MSCs, demonstrating their unique characteristics and potential applications in therapeutic strategies. The identification of specific gene expression profiles differentiates hPD-MSCs from other mesenchymal cells and opens new avenues for research into their role in pancreatic function and neural development.

Emerging roles of astrocytes as immune effectors in the central nervous system

The astrocyte, a major glial cell type in the central nervous system (CNS), is widely regarded as a functionally diverse mediator of homeostasis. During development and throughout adulthood, astrocytes have essential roles, such as providing neuron metabolic support, modulating synaptic function, and maintaining the blood-brain barrier (BBB). Recent evidence continues to underscore their functional heterogeneity and importance for CNS maintenance, as well as how these cells ensure optimal CNS and immune responses to disease, acute trauma, and infection. Advances in our understanding of neuroimmune interactions complement our knowledge of astrocyte functional heterogeneity, where astrocytes are now regarded as key effectors and propagators of immune signaling. This shift in perspective highlights the role of astrocytes not merely as support cells, but as active participants in CNS immune responses.

Reprogramming natural killer cells for cancer therapy

The last decade has seen rapid development in the field of cellular immunotherapy, particularly in regard to chimeric antigen receptor (CAR)-modified T cells. However, challenges, such as severe treatment-related toxicities and inconsistent quality of autologous products, have hindered the broader use of CAR-T cell therapy, highlighting the need to explore alternative immune cells for cancer targeting. In this regard, natural killer (NK) cells have been extensively studied in cellular immunotherapy and were found to exert cytotoxic effects without being restricted by human leukocyte antigen and have a lower risk of causing graft-versus-host disease; making them favorable for the development of readily available "off-the-shelf" products. Clinical trials utilizing unedited NK cells or reprogrammed NK cells have shown early signs of their effectiveness against tumors. However, limitations, including limited in vivo persistence and expansion potential, remained. To enhance the antitumor function of NK cells, advanced gene-editing technologies and combination approaches have been explored. In this review, we summarize current clinical trials of antitumor NK cell therapy, provide an overview of innovative strategies for reprogramming NK cells, which include improvements in persistence, cytotoxicity, trafficking and the ability to counteract the immunosuppressive tumor microenvironment, and also discuss some potential combination therapies.

Cellular regenerative therapy in stress urinary incontinence: new frontiers?-a narrative review

Background and Objective

Even if treatment with stem cells has been shown to be safe and effective in many patients with stress urinary incontinence (SUI), there is still room for improvement using other regenerative medicine alternatives. Since the beneficial effects of stem cells are probably mediated by secretion of factors rather than by the cells themselves there is a good rationale for further exploring the therapeutic effects of the secretome and/or its components. However, homing factors such as stromal derived growth factor 1 (SDF-1; CXCL12), stimulation of stem cell growth and stem cell mobilization in vivo using low intensity shock wave therapy (Li-ESWT) or regenerative electrical stimulation (RES), are also promising approaches.

Methods

A literature search was performed based on PubMed, Scopus and Google Scholar. The search criteria included original basic science articles, systematic reviews and randomized control trials. All studies were published between 2000 and 2023. Selected, peer-reviewed studies were further analyzed to identify those of relevance. Keywords searched included: "female stress incontinence", "homing factors", "CXCL12", "secretome", "low intensity shockwave therapy" and "regenerative electrical stimulation". The peer-reviewed publications on the key word subjects that contained a novel addition to the existing body of literature were included.

Key Content and Findings

There is evidence from studies on non-human primates (NHPs) with experimental urinary sphincter injury that CXCL12 can restore sphincter structure and function. Studies with homing factors in human patients with SUI are still to be performed. A large number of clinical studies on the use of secretome or secretome products from mesenchymal stem cells (MSCs) on indications other than human SUI are already available. However, controlled clinical trials on patients with SUI, have to the best of our knowledge, not yet been performed. Also, RES has not been studied in patients with SUI. In contrast, there is clinical evidence that Li-ESWT may improve female SUI.

Conclusions

Treatment with homing factors, MSC secretome/secretome components, Li-ESWT and RES are promising frontiers in the treatment of human SUI caused by sphincter damage.

Cryo-EM structure of monomeric CXCL12-bound CXCR4 in the active state

CXCR4 binding of its endogenous agonist CXCL12 leads to diverse functions, including bone marrow retention of hematopoietic progenitors and cancer metastasis. However, the structure of the CXCL12-bound CXCR4 remains unresolved despite available structures of CXCR4 in complex with antagonists. Here, we present the cryoelectron microscopy (cryo-EM) structure of the CXCL12-CXCR4-Gi complex at an overall resolution of 2.65 Å. CXCL12 forms a 1:1 stoichiometry complex with CXCR4, following the two-site model. The first 8 amino acids of mature CXCL12 are crucial for CXCR4 activation by forming polar interactions with minor sub-pocket residues in the transmembrane binding pocket. The 3.2-Å distance between V3 of CXCL12 and the "toggle switch" W6.48 marks the deepest insertion among all chemokine-receptor pairs, leading to conformational changes of CXCR4 for G protein activation. These results, combined with functional assays and computational analysis, provide the structural basis for CXCR4 activation by CXCL12.

Proteomic insights into breast cancer response to brain cell-secreted factors

The most devastating feature of cancer cells is their ability to metastasize to distant sites in the body. HER2 + and TN breast cancers frequently metastasize to the brain and stay potentially dormant for years until favorable conditions support their proliferation. The sheltered and delicate nature of the brain prevents, however, early disease detection and effective delivery of therapeutic drugs. Moreover, the challenges associated with the acquisition of brain biopsies add compounding difficulties to exploring the mechanistic aspects of tumor development. To provide insights into the determinants of cancer cell behavior at the brain metastatic site, this study was aimed at exploring the early response of HER2 + breast cancer cells (SKBR3) to factors present in the brain perivascular niche. The neural microenvironment was simulated by using the secretome of a set of brain cells that come first in contact with the cancer cells upon crossing the blood brain barrier, i.e., endothelial cells, astrocytes, and microglia. Cytokine microarrays were used to investigate the secretome mediators of intercellular communication, and proteomic technologies for assessing the changes in the behavior of cancer cells upon exposure to the brain cell-secreted factors. The cytokines detected in the brain secretomes were supportive of inflammatory conditions, while the SKBR3 cells secreted numerous cancer-promoting growth factors that were either absent or present in lower abundance in the brain cell cultures, indicating that upon exposure the SKBR3 cells may have been deprived of favorable conditions for optimal growth. Altogether, the results suggest that the exposure of SKBR3 cells to the brain cell-secreted factors altered their growth potential and drove them toward a state of quiescence, with broader overall outcomes that affected cellular metabolism, adhesion and immune response processes. The findings of this study underscore the key role played by the neural niche in shaping the behavior of metastasized cancer cells, provide insights into the cellular cross-talk that may lead cancer cells into dormancy, and highlight novel opportunities for the development of metastatic breast cancer therapeutic strategies.

Protection of stromal cell-derived factor-1 SDF-1/CXCL12 against proteases yields improved skin wound healing

SDF-1/CXCL12 is a unique chemotactic factor with multiple functions on various types of precursor cells, all carrying the cognate receptor CXCR4. Whereas individual biological functions of SDF-1/CXCL12 have been well documented, practical applications in medicine are insufficiently studied. This is explained by the complex multifunctional biology of SDF-1 with systemic and local effects, critical dependence of SDF-1 activity on aminoterminal proteolytic processing and limited knowledge of applicable modulators of its activity. We here present new insights into modulation of SDF-1 activity in vitro and in vivo by a macromolecular compound, chlorite-oxidized oxyamylose (COAM). COAM prevented the proteolytic inactivation of SDF-1 by two inflammation-associated proteases: matrix metalloproteinase-9/MMP-9 and dipeptidylpeptidase IV/DPPIV/CD26. The inhibition of proteolytic inactivation was functionally measured by receptor-mediated effects, including intracellular calcium mobilization, ERK1/2 phosphorylation, receptor internalization and chemotaxis of CXCR4-positive cells. Protection of SDF-1/CXCL12 against proteolysis was dependent on electrostatic COAM-SDF-1 interactions. By in vivo experiments in mice, we showed that the combination of COAM with SDF-1 delivered through physiological fibrin hydrogel had beneficial effect for the healing of skin wounds. Collectively, we show that COAM protects SDF-1 from proteolytic inactivation, maintaining SDF-1 biological activities. Thus, protection from proteolysis by COAM represents a therapeutic strategy to prolong SDF-1 bioavailability for wound healing applications.

HDAC Inhibition Increases CXCL12 Secretion to Recruit Natural Killer Cells in Peripheral T-cell Lymphoma

Peripheral T-cell lymphoma (PTCL) is a heterogeneous and aggressive disease with a poor prognosis. Histone deacetylase (HDAC) inhibitors have shown inhibitory effects on PTCL. A better understanding of the therapeutic mechanism underlying the effects of HDAC inhibitors could help improve treatment strategies. Herein, we found that high expression of HDAC3 is associated with poor prognosis in PTCL. HDAC3 inhibition suppressed lymphoma growth in immunocompetent mice but not in immunodeficient mice. HDAC3 deletion delayed the progression of lymphoma, reduced the lymphoma burden in the thymus, spleen, and lymph nodes, and prolonged the survival of mice bearing N-methyl-N-nitrosourea-induced lymphoma. Furthermore, inhibiting HDAC3 promoted the infiltration and enhanced the function of natural killer (NK) cells. Mechanistically, HDAC3 mediated ATF3 deacetylation, enhancing its transcriptional inhibitory activity. Targeting HDAC3 enhanced CXCL12 secretion through an ATF3-dependent pathway to stimulate NK-cell recruitment and activation. Finally, HDAC3 suppression improved the response of PTCL to conventional chemotherapy. Collectively, this study provides insights into the mechanism by which HDAC3 regulates ATF3 activity and CXCL12 secretion, leading to immune infiltration and lymphoma suppression. Combining HDAC3 inhibitors with chemotherapy may be a promising strategy for treating PTCL. Significance: Targeting HDAC3 suppresses progression of T-cell lymphoma by activating ATF3 to induce secretion of CXCL12 and promote infiltration of NK cells, providing an immunostimulatory approach for treating T-cell lymphoma patients.

Enhancing high-quality fat survival: A novel strategy using cell-free fat extract

High-quality fat (HQF) improves the survival rate of fat and volumetric filling compared to traditional Coleman fat. However, this HQF strategy inevitably leads to a significant amount of unused fat being wasted. "CEFFE" (cell-free fat extract) is an acellular aqueous-phase liquid, rich in bioactive proteins. The remaining fat from preparing HQF can be further processed into CEFFE to promote the survival of HQF. HQF was obtained and the remaining fat was processed into CEFFE, then HQF was transplanted subcutaneously in nude mice. Animal studies showed that CEFFE significantly improved the survival rate of HQF. Histological analysis revealed that CEFFE improved the survival rate of HQF, by enhancing cell proliferation activity, reducing apoptosis, increasing angiogenesis, and improving the inflammatory state. Under simulated anaerobic conditions, CEFFE also improved the viability of HQF. In vitro, studies demonstrated that CEFFE enhanced the survival rate of HQF through multiple mechanisms. Transcriptomic analysis and qPCR showed that CEFFE increased the expression of angiogenesis-related genes in ADSCs while enhancing their proliferation-related gene expression and suppressing the expression of three differentiation-related genes. Moreover, functional experiments demonstrated that CEFFE-induced ADSCs exhibited stronger proliferation and adipogenic differentiation abilities. Tube formation and migration assays revealed that CEFFE promoted tube formation and migration of HUVECs, indicating its inherent pro-angiogenic properties. CEFFE facilitated the development of M0 to M2 macrophages, suggesting its role in improving the inflammatory state. This innovative clinical strategy optimizes HQF transplantation strategy, minimizing fat wastage and enhancing the efficiency of fat utilization.

CXCL14 and miR-4484 serves as potential salivary biomarkers for early detection of peri-implantitis

Peri-implantitis develops in 43.3% of implant patients, which affects tissues around the implant that may ultimately cause implant loss if not treated properly. Due to difficulties in detecting peri-implantitis in its early phases, implant failures are constantly on the rise. Therefore, new specific molecular markers need to be identified to prevent or limit disease progression in peri-implantitis patients. We investigated levels of CXCL9, CXCL12, and CXCL14 in saliva samples of 45 patients with commercially pure grade 4/5 Titanium-Aluminum-Vanadium implants. We analyzed the correlation of the chemokine levels using Pearson's Correlation test and investigated their power to discriminate peri-implantitis vs. non-peri-implantitis patients using receiver operating characteristic analysis. Our in silico investigation revealed CXCL9, CXCL12, and CXCL14 as predicted targets of miR-4484, which has been demonstrated as a powerful biomarker candidate for early detection of peri-implantitis in our previous study. We measured high CXCL9 and low CXCL14 levels in the saliva of peri-implantitis patients. We also reported that the CXCL14 level showed a significant positive correlation with miR-4484. Besides, CXCL14 together with miR-4484 in saliva differentiated peri-implantitis patients from non-peri-implantitis individuals with 100% success. We offer differential expressions of CXCL14 and miR-4484 in the saliva of patients with peri-implantitis as potential salivary biomarkers for early detection of this disease.

Injectable thermo-responsive Poloxamer hydrogel/methacrylate gelatin microgels stimulates bone regeneration through biomimetic programmed release of SDF-1a and IGF-1

Injectable hydrogels, offering adaptable drug delivery of growth factors (GFs), hold promise for treating bone defects. To optimize osteogenic efficacy, the release of GFs should mirror the natural bone healing. We developed an injectable thermo-responsive hydrogel/microgels platform for dual GF delivery for bone regeneration. Stromal cell-derived factor-1 alpha (SDF-1a) and the Methacrylate Gelatin (GelMA) microgels which encapsulated insulin-like growth factor-1 (IGF-1) loaded liposomes (Ls) were introduced into Poloxamer 407 (P407) hydrogel matrix. This system achieved the biomimetic release profile of SDF-1a and IGF-1, which covered the early stage from day 1 to 7 and the continuous stage from day 5 to 21, respectively. In vitro study confirmed the enhanced migration, osteogenic biomarker expression, and matrix mineralization of the bone marrow mesenchymal stem cells (BMSCs) co-cultivated with the dual GFs delivering hydrogel/microgels. Transcriptome sequencing revealed that the potential mechanism was associated with mitogen-activated protein kinase (MAPK) signaling activation and its downstream ribosomal protein S6 kinase 2 (RSK2) upregulation. In a critical-sized calvarial defect model in Sprague-Dawley (SD) rats, the injectable hydrogel/microgels system promoted significant bone regeneration. Collectively, our study suggested the current hydrogel/microgels system with the biomimetic release of SDF-1a and IGF-1 efficiently promoted bone regeneration, informing the future development of GF delivery systems intended for bone regeneration therapies.

Expanding the horizons of targeted protein degradation: A non-small molecule perspective

Targeted protein degradation (TPD) represented by proteolysis targeting chimeras (PROTACs) marks a significant stride in drug discovery. A plethora of innovative technologies inspired by PROTAC have not only revolutionized the landscape of TPD but have the potential to unlock functionalities beyond degradation. Non-small-molecule-based approaches play an irreplaceable role in this field. A wide variety of agents spanning a broad chemical spectrum, including peptides, nucleic acids, antibodies, and even vaccines, which not only prove instrumental in overcoming the constraints of conventional small molecule entities but also provided rapidly renewing paradigms. Herein we summarize the burgeoning non-small molecule technological platforms inspired by PROTACs, including three major trajectories, to provide insights for the design strategies based on novel paradigms.

Th2-skewed peripheral T-helper cells drive B-cells in allergic bronchopulmonary aspergillosis

INTRODUCTION

Patients with allergic bronchopulmonary aspergillosis (ABPA) suffer from repeated exacerbations. The involvement of T-cell subsets remains unclear.

METHODS

We enrolled ABPA patients, asthma patients and healthy controls. T-helper type 1 (Th1), 2 (Th2) and 17 (Th17) cells, regulatory T-cells (Treg) and interleukin (IL)-21+CD4+T-cells in total or sorted subsets of peripheral blood mononuclear cells and ABPA bronchoalveolar lavage fluid (BALF) were analysed using flow cytometry. RNA sequencing of subsets of CD4+T-cells was done in exacerbated ABPA patients and healthy controls. Antibodies of T-/B-cell co-cultures in vitro were measured.

RESULTS

ABPA patients had increased Th2 cells, similar numbers of Treg cells and decreased circulating Th1 and Th17 cells. IL-5+IL-13+IL-21+CD4+T-cells were rarely detected in healthy controls, but significantly elevated in the blood of ABPA patients, especially the exacerbated ones. We found that IL-5+IL-13+IL-21+CD4+T-cells were mainly peripheral T-helper (Tph) cells (PD-1+CXCR5-), which also presented in the BALF of ABPA patients. The proportions of circulating Tph cells were similar among ABPA patients, asthma patients and healthy controls, while IL-5+IL-13+IL-21+ Tph cells significantly increased in ABPA patients. Transcriptome data showed that Tph cells of ABPA patients were Th2-skewed and exhibited signatures of follicular T-helper cells. When co-cultured in vitro, Tph cells of ABPA patients induced the differentiation of autologous B-cells into plasmablasts and significantly enhanced the production of IgE.

CONCLUSION

We identified a distinctly elevated population of circulating Th2-skewed Tph cells that induced the production of IgE in ABPA patients. It may be a biomarker and therapeutic target for ABPA.

Immune System Dysregulation in the Progression of Multiple Sclerosis: Molecular Insights and Therapeutic Implications

Multiple sclerosis (MS), a prevalent neurological disorder, predominantly affects young adults and is characterized by chronic autoimmune activity. The study explores the immune system dysregulation in MS, highlighting the crucial roles of immune and non-neuronal cells in the disease's progression. This review examines the dual role of cytokines, with some like IL-6, TNF-α, and interferon-gamma (IFN-γ) promoting inflammation and CNS tissue injury, and others such as IL-4, IL-10, IL-37, and TGF-β fostering remyelination and protecting against MS. Elevated chemokine levels in the cerebrospinal fluid (CSF), including CCL2, CCL5, CXCL10, CXCL13, and fractalkine, are analyzed for their role in facilitating immune cell migration across the blood-brain barrier (BBB), worsening inflammation and neurodegeneration. The study also delves into the impact of auto-antibodies targeting myelin components like MOG and AQP4, which activate complement cascades leading to further myelin destruction. The article discusses how compromised BBB integrity allows immune cells and inflammatory mediators to infiltrate the CNS, intensifying MS symptoms. It also examines the involvement of astrocytes, microglia, and oligodendrocytes in the disease's progression. Additionally, the effectiveness of immunomodulatory drugs such as IFN-β and CD20-targeting monoclonal antibodies (e.g., rituximab) in modulating immune responses is reviewed, highlighting their potential to reduce relapse rates and delaying MS progression. These insights emphasize the importance of immune system dysfunction in MS development and progression, guiding the development of new therapeutic strategies. The study underscores recent advancements in understanding MS's molecular pathways, opening avenues for more targeted and effective treatments.

Tumor cell derived osteopontin and prostaglandin E2 synergistically promote the expansion of myeloid derived suppressor cells during the tumor immune escape phase

The immune escape stage in cancer immunoediting is a pivotal feature, transitioning immune-controlled tumor dormancy to progression, and augmenting invasion and metastasis. Tumors employ diverse mechanisms for immune escape, with generating immunosuppressive cells from skewed hematopoiesis being a crucial mechanism. This led us to suggest that tumor cells with immune escape properties produce factors that induce dysregulations in hematopoiesis. In support of this suggestion, this study found that mice bearing advanced-stage tumors exhibited dysregulated hematopoiesis characterized by the development of splenomegaly, anemia, extramedullary hematopoiesis, production of immunosuppressive mediators, and expanded medullary myelopoiesis. Further ex vivo studies exhibited that conditioned medium derived from EL4lu2 cells could mediate the expansion of myeloid derived suppressor cells (MDSCs) in bone marrow cell cultures. The protein array profiling results revealed the presence of elevated levels of osteopontin (OPN), prostaglandin E2 (PGE2) and interleukin 17 (IL-17) in the culture medium derived from EL4luc2 cells. Accordingly, substantial levels of these factors were also detected in the sera of mice bearing EL4luc2 tumors. Among these factors, only PGE2 alone could increase the number of MDSCs in the BM cell cultures. This effect of PGE2 was significantly potentiated by the presence of OPN but not IL-17. Finally, in vitro treatment of EL4luc2 cells with pioglitazone, a modulator of OPN and cyclooxygenase 2 (COX-2) resulted in a significant reduction in cell proliferation in EL4luc2 cells. Our findings highlight the significant role played by tumor cell-derived OPN and PGE2 in fostering the expansion of medullary MDSCs and in promoting tumor cell proliferation. Furthermore, these intertwined cancer processes could be key targets for pioglitazone intervention.

SPI1-mediated CXCL12 expression in bladder cancer affects the recruitment of tumor-associated macrophages

Bladder cancer (BC) originates principally from the epithelial compartment of the bladder. The immune system and its diverse players, chemokines, in particular, have been related to the responses against BC. The goal of the study here was to examine if C-X-C motif chemokine 12 (CXCL12) in BC cells could manipulate protumorigenic properties of tumor-associated macrophages (TAMs) which affects anticancer immunity supporting tumor development in the tumor microenvironment. CXCL12 was found to be overexpressed in BC and predicted poor survival. CXCL12 in BC was associated with multiple immune cell infiltrations, with TAM infiltration playing a key role. CXCL12 elevated chemotaxis of TAMs. CXCL12 downregulation inhibited cellular activity and TAM and suppressed the ability of TAMs to secrete inflammatory factors and MMP9. Furthermore, chromatin immunoprecipitation analysis revealed that SPI1 was localized to the CXCL12 promoter in BC cells, suggesting that CXCL12 serves a direct target of SPI1, which was consistent with the fact that SPI1 reversed the repressive effects of si-CXCL12 on BC cell activity and TAM recruitment in vitro and in vivo. Collectively, these findings suggest that SPI1 is involved in modulating TAM recruitment, representing a new mechanism through which it may influence tumor growth. This may be partly mediated by regulating CXCL12 expression.

Directing the migration of serum-free, ex vivo-expanded Vγ9Vδ2 T cells

Vγ9Vδ2 T cells represent a promising cancer therapy platform because the implementation of allogenic, off-the-shelf product candidates is possible. However, intravenous administration of human Vγ9Vδ2 T cells manufactured under good manufacturing practice (GMP)-compliant, serum-free conditions are not tested easily in most mouse models, mainly because they lack the ability to migrate from the blood to tissues or tumors. We demonstrate that these T cells do not migrate from the circulation to the mouse bone marrow (BM), the site of many malignancies. Thus, there is a need to better characterize human γδ T-cell migration in vivo and develop strategies to direct these cells to in vivo sites of therapeutic interest. To better understand the migration of these cells and possibly influence their migration, NSG mice were conditioned with agents to clear BM cellular compartments, i.e., busulfan or total body irradiation (TBI), or promote T-cell migration to inflamed BM, i.e., incomplete Freund's adjuvant (IFA), prior to administering γδ T cells. Conditioning with TBI, unlike busulfan or IFA, increases the percentage and number of γδ T cells accumulating in the mouse BM, and cells in the peripheral blood (PB) and BM display identical surface protein profiles. To better understand the mechanism by which cells migrate to the BM, mice were conditioned with TBI and administered γδ T cells or tracker-stained red blood cells. The mechanism by which γδ T cells enter the BM after radiation is passive migration from the circulation, not homing. We tested if these ex vivo-expanded cells can migrate based on chemokine expression patterns and showed that it is possible to initiate homing by utilizing highly expressed chemokine receptors on the expanded γδ T cells. γδ T cells highly express CCR2, which provides chemokine attraction to C-C motif chemokine ligand 2 (CCL2)-expressing cells. IFNγ-primed mesenchymal stromal cells (MSCs) (γMSCs) express CCL2, and we developed in vitro and in vivo models to test γδ T-cell homing to CCL2-expressing cells. Using an established neuroblastoma NSG mouse model, we show that intratumorally-injected γMSCs increase the homing of γδ T cells to this tumor. These studies provide insight into the migration of serum-free, ex vivo-expanded Vγ9Vδ2 T cells in NSG mice, which is critical to understanding the fundamental properties of these cells.

Single-cell RNA sequencing reveals roles of unique retinal microglia types in early diabetic retinopathy

BACKGROUND

The pathophysiological mechanisms of diabetic retinopathy (DR), a blinding disease, are intricate. DR was thought to be a microvascular disease previously. However, growing studies have indicated that the retinal microglia-induced inflammation precedes microangiopathy. The binary concept of microglial M1/M2 polarization paradigms during inflammatory activation has been debated. In this study, we confirmed microglia had the most significant changes in early DR using single-cell RNA sequencing.

METHODS

A total of five retinal specimens were collected from donor SD rats. Changes in various cells of the retina at the early stage of DR were analyzed using single-cell sequencing technology.

RESULTS

We defined three new microglial subtypes at cellular level, including two M1 types (Egr2+ M1 and Egr2- M1) and one M2 type. We also revealed the anatomical location between these subtypes, the dynamic changes of polarization phenotypes, and the possible activation sequence and mutual activation regulatory mechanism of different cells. Furthermore, we constructed an inflammatory network involving microglia, blood-derived macrophages and other retinal nonneuronal cells. The targeted study of new disease-specific microglial subtypes can shorten the time for drug screening and clinical application, which provided insight for the early control and reversal of DR.

CONCLUSIONS

We found that microglia show the most obvious differential expression changes in early DR and reveal the changes in microglia in a high-glucose microenvironment at the single-cell level. Our comprehensive analysis will help achieve early reversal and control the occurrence and progression of DR.

The Utility of Miniaturized Adsorbers in Exploring the Cellular and Molecular Effects of Blood Purification: A Pilot Study with a Focus on Immunoadsorption in Multiple Sclerosis

Immunoadsorption (IA) has proven to be clinically effective in the treatment of steroid-refractory multiple sclerosis (MS) relapses, but its mechanism of action remains unclear. We used miniaturized adsorber devices with a tryptophan-immobilized polyvinyl alcohol (PVA) gel sorbent to mimic the IA treatment of patients with MS in vitro. The plasma was screened before and after adsorption with regard to disease-specific mediators, and the effect of the IA treatment on the migration of neutrophils and the integrity of the endothelial cell barrier was tested in cell-based models. The in vitro IA treatment with miniaturized adsorbers resulted in reduced plasma levels of cytokines and chemokines. We also found a reduced migration of neutrophils towards patient plasma treated with the adsorbers. Furthermore, the IA-treated plasma had a positive effect on the endothelial cell barrier's integrity in the cell culture model. Our findings suggest that IA results in a reduced infiltration of cells into the central nervous system by reducing leukocyte transmigration and preventing blood-brain barrier breakdown. This novel approach of performing in vitro blood purification therapies on actual patient samples with miniaturized adsorbers and testing their effects in cell-based assays that investigate specific hypotheses of the pathophysiology provides a promising platform for elucidating the mechanisms of action of those therapies in various diseases.

Extracellular targeted protein degradation: an emerging modality for drug discovery

Targeted protein degradation (TPD) has emerged in the past decade as a major new drug modality to remove intracellular proteins with bispecific small molecules that recruit the protein of interest (POI) to an E3 ligase for degradation in the proteasome. Unlike classic occupancy-based drugs, intracellular TPD (iTPD) eliminates the target and works catalytically, and so can be more effective and sustained, with lower dose requirements. Recently, this approach has been expanded to the extracellular proteome, including both secreted and membrane proteins. Extracellular targeted protein degradation (eTPD) uses bispecific antibodies, conjugates or small molecules to degrade extracellular POIs by trafficking them to the lysosome for degradation. Here, we focus on recent advances in eTPD, covering degrader systems, targets, molecular designs and parameters to advance them. Now almost any protein, intracellular or extracellular, is addressable in principle with TPD.

The causality between systemic inflammatory regulators and chronic respiratory diseases: A bidirectional Mendelian-randomization study

INTRODUCTION

Accumulative evidence suggests the associations between systemic inflammatory regulators and chronic respiratory diseases (CRDs). However, the intrinsic causation remains implicit. Therefore, this study aimed to examine causative associations by mendelian randomization (MR) and to identify valuable active factors.

METHODS

Based on data from the GWAS database, we performed MR analyses of 41 serum cytokines from 8,293 Finnish and European descent cohorts from GBMI and UKBB for five major CRDs. We mainly applied inverse variance weighted regression, supplemented by MR-Egger regression, weighted median, maximum likelihood, weighted mode, and simple mode algorithms. Moreover, sensitivity analyses were conducted using Cochrane's Q test, MR-Egger intercept, MR-PRESSO Global test and MR-Steiger filtering. Eventually, the consistency of MR results was assessed by leave-one-out.

RESULTS

Our results suggest that 12 genetically predicted systemic inflammatory regulators probably participate in the progression of CRDs, including four risk factors (IL-1RA, IL-4, MIP-1A, PDGF-BB) and one protective factor (IL-6) in IPF, two protective factors (SCF, SDF-1A) in COPD, and two protective factors (SCF, SDF-1A) in asthma, two protective factors (GROA, IL-2RA) were also included in asthma, whereas only one factor (HGF) was protective against bronchiectasis. Additionally, two protective factors (FGF-BASIC, G-CSF) were identified in sarcoidosis. Sensitivity analyses showed no horizontal pleiotropy and significant heterogeneity. Finally, based on the findings of inverse MR analysis, no inverse causal association was uncovered, confirming the robustness of results.

CONCLUSION

Our study unearths potential associations between systemic inflammatory modulators and common CRDs, providing new insights for inflammation-mediated CRD prevention and therapeutic approaches.