Macrophage Infiltration Research Articles

SDIMMMER: A Proposed Clinical Approach to Optimize Cellular Physiology in Regenerative Medicine.

SDIMMMER is an acronym intended for use in both clinical practice and medical research. It facilitates a comprehensive evaluation of a patient's metabolic profile and serves as a mnemonic for the following key assessment areas: Sleep, Diet, Microbiome, Metabolism, Medications, Exams, and Rehabilitation. In the clinical setting, SDIMMMER's primary objective is to monitor and manage the patient's metabolic status, particularly targeting low-grade chronic systemic inflammation, a hallmark of metabolic syndrome (MS). This inflammatory condition is characterized by elevated levels of circulating inflammatory cytokines and increased macrophage infiltration in peripheral tissues. SDIMMMER aims to enhance the effectiveness of ortho biological treatments by elevating growth factor levels, thereby enhancing patient outcomes. Additionally, SDIMMMER emphasizes guiding patients toward positive lifestyle changes to improve overall quality of life and foster a healthier metabolism. SDIMMMER introduces a patient metabolic profile quantification tool comprising 7 domains, totaling 35 items. Additionally, an instructional guide is provided to facilitate the application process. Its versatility spans various clinical and research domains, showcasing its potential to positively influence multiple fields.

SFRP2 modulates functional phenotype transition and energy metabolism of macrophages during diabetic wound healing.

Diabetic foot ulcer (DFU) is a serious complication of diabetes mellitus, which causes great health damage and economic burden to patients. The pathogenesis of DFU is not fully understood. We screened wound healing-related genes using bioinformatics analysis, and full-thickness skin injury mice model and cellular assays were used to explore the role of target genes in diabetic wound healing. SFRP2 was identified as a wound healing-related gene, and the expression of SFRP2 is associated with immune cell infiltration in DFU. In vivo study showed that suppression of SFRP2 delayed the wound healing process of diabetic mice, impeded angiogenesis and matrix remodeling, but did not affect wound healing process of control mice. In addition, suppression of SFRP2 increased macrophage infiltration and impeded the transition of macrophages functional phenotypes during diabetic wound healing, and affected the transcriptome signatures-related to inflammatory response and energy metabolism at the early stage of wound healing. Extracellular flux analysis (EFA) showed that suppression of SFRP2 decreased mitochondrial energy metabolism and increased glycolysis in injury-related macrophages, but impeded both glycolysis and mitochondrial energy metabolism in inflammatory macrophages. In addition, suppression of SFRP2 inhibited wnt signaling-related genes in macrophages. Treatment of AAV-SFRP2 augmented wound healing in diabetic mice and demonstrated the therapeutic potential of SFRP2. In conclusions, SFRP2 may function as a wound healing-related gene in DFU by modulating functional phenotype transition of macrophages and the balance between mitochondrial energy metabolism and glycolysis.

Antifibrotic effect of disulfiram on bleomycin-induced lung fibrosis in mice and its impact on macrophage infiltration

The accumulation of monocyte-derived macrophages in the lung tissue during inflammation is important for the pathogenesis of fibrotic lung disease. Deficiencies in chemokine receptors CCR2 and CCR5 and their ligands, which mediate monocyte/macrophage migration, ameliorate bleomycin (BLM)-induced lung fibrosis. Disulfiram (DSF), which is used to treat alcoholism because of its aldehyde dehydrogenase (ALDH)-inhibiting effect, inhibits monocyte/macrophage migration by inhibiting FROUNT, an intracellular regulator of CCR2/CCR5 signalling. Here, we investigated the antifibrotic effect of oral DSF administration in a mouse model of BLM-induced lung fibrosis, focusing on macrophage response and fibrosis progression. The direct inhibitory activity of DSF on monocyte migration was measured using the Boyden chamber assay and compared with that of DSF-related inhibitors with different FROUNT-inhibition activities. Quantitative PCR was used to determine the expression of fibrosis-promoting genes in the lung tissue. DSF significantly suppressed macrophage infiltration into lung tissues and attenuated BLM-induced lung fibrosis. DSF and its metabolites, diethyldithiocarbamate (DDC) and copper diethyldithiocarbamate (Cu(DDC)2), inhibited monocyte migration toward the culture supernatant of primary mouse lung cells mainly comprising CCL2, whereas cyanamide, another ALDH inhibitor, did not. DSF, with higher inhibitory activity against FROUNT than DDC and Cu(DDC)2, inhibited monocyte migration most strongly. In BLM-induced fibrotic lung tissues, profibrotic factors were highly expressed but were reduced by DSF treatment. These results suggest DSF inhibits macrophage infiltration, which might be attributed to its inhibitory effect on FROUNT, and attenuates BLM-induced lung fibrosis. In addition, multiplex immunofluorescence imaging revealed reduced infiltration of S100A4+ macrophages into the lungs in DSF-treated mice and high expression of FROUNT in S100A4+ macrophages in idiopathic pulmonary fibrosis (IPF). These findings underscore the potential of macrophage-targeted therapy with DSF as a promising drug repositioning approach for treating fibrotic lung diseases, including IPF.

Cellular and Molecular Mechanisms of Hypertrophy of Ligamentum Flavum.

Hypertrophy of the ligamentum flavum (HLF) is a common contributor to lumbar spinal stenosis (LSS). Fibrosis is a core pathological factor of HLF resulting in degenerative LSS and associated low back pain. Although progress has been made in HLF research, the specific molecular mechanisms that promote HLF remain to be defined. The molecular factors involved in the onset of HLF include increases in inflammatory cytokines such as transforming growth factor (TGF)-β, matrix metalloproteinases, and pro-fibrotic growth factors. In this review, we discuss the current understanding of the mechanisms involved in HLF with a particular emphasis on aging and mechanical stress. We also discuss in detail how several pathomechanisms such as fibrosis, proliferation and apoptosis, macrophage infiltration, and autophagy, in addition to several molecular pathways involving TGF-β1, mitogen-activated protein kinase (MAPKs), and nuclear factor-κB (NF-κB) signaling, PI3K/AKT signaling, Wnt signaling, micro-RNAs, extracellular matrix proteins, reactive oxygen species (ROS), etc. are involved in fibrosis leading to HLF. We also present a summary of the current advancements in preclinical animal models for HLF research. In addition, we update the current and potential therapeutic targets/agents against HLF. An improved understanding of the molecular processes behind HLF and a novel animal model are key to developing effective LSS prevention and treatment strategies.

Low-intensity pulsed ultrasound improves metabolic dysregulation in obese mice by suppressing inflammation and extracellular matrix remodeling

Chronic inflammation in white adipose tissue is crucial in obesity and related metabolic disorders. Low-intensity pulsed ultrasound (LIPUS) is renowned for its anti-inflammatory effects as a non-invasive treatment, yet its precise role in obesity has been uncertain. Our study investigates the therapeutic effect of LIPUS and its underlying mechanism on obesity in mice, thereby offering a novel approach for non-invasive treatment of obesity and associated metabolic disorders for human. Male C57BL/6J mice aged 10 weeks were fed a high-fat diet (HFD) for 8 weeks to establish obesity model, then underwent 8 weeks of LIPUS (frequency: 1.0 MHz, duty cycle: 20 %, Isata: 58–61 mW/cm2, 20 min per day) stimulation of the epididymal white adipose tissue. Fat and lean mass were measured using nuclear magnetic resonance (NMR), while energy homeostasis was evaluated using metabolic cages. Insulin resistance was assessed using glucose tolerance tests (GTT) and insulin tolerance tests (ITT). Regulatory mechanisms were explored using RNA sequencing. Results showed that LIPUS significantly reduced obesity markers in obese mice, including body and adipose tissue weight, and improved insulin resistance, without affecting food intake. RNA sequencing showed 250 up-regulated and 351 down-regulated genes between HFD-LIPUS group and HFD-Sham group, suggesting anti-inflammatory action. Quantitative PCR confirmed reduced pro-inflammatory gene expression and macrophage infiltration in eWAT. Gene set enrichment analysis showed decreased NF-κB signaling and extracellular matrix-receptor interactions in LIPUS-treated mice. Thus, LIPUS effectively mitigates metabolic dysregulation in HFD-induced obesity through inflammation suppression and extracellular matrix remodeling, which provides a potential physical therapy for metabolic syndrome in clinic.

Drp1 Promotes Macrophage M1 Polarization and Inflammatory Response in Autoimmune Myocarditis by Driving Mitochondrial Fission.

Autoimmune myocarditis (AM) is characterized by an intricate inflammatory response within the myocardium. Dynamin-related protein 1 (Drp1), a pivotal modulator of mitochondrial fission, plays a role in the pathogenesis of various diseases. A myosin-induced experimental autoimmune myocarditis (EAM) mouse model was successfully established. Flow cytometry was employed to detect M1/M2-like macrophages. Mitochondrial fragmentation was assessed using Mito-Tracker Red CMXRos. Drp1 was upregulated and activated in EAM mice. Depletion of Drp1 was observed to mitigate inflammation, macrophage infiltration and M1 polarization within the cardiac tissue of EAM mice. In M1-like macrophages derived from the hearts of EAM mice, Drp1 was found to promote mitochondrial fission and diminish mitochondrial fusion. Furthermore, the depletion of Drp1 reduced the NF-κB-related pro-inflammatory response in EAM-associated M1-like macrophages. Drp1 drives mitochondrial fission in macrophages, driving their M1 polarization and the subsequent inflammatory response. Drp1 may represent an effective target for the prevention and treatment of AM.

HPV16 E6-induced M2 macrophage polarization in the cervical microenvironment via exosomal miR-204-5p

The persistent infection of high-risk human papillomavirus (HPV) and the progression of cervical cancer necessitate the involvement of microenvironmental immunity. As cervical lesions advance, there is an observed increase in the infiltration of type 2 (M2) macrophages. However, the precise mechanism driving this increased infiltration of M2 macrophages remains unclear. In this study, we investigated the role of exosomes in polarising M2 macrophages in cervical lesions associated with HPV E6. Through the analysis of bioinformatics data and clinical specimens, we discovered a positive correlation between HPV E6/E7 mRNA copy number and the level of M2 macrophage infiltration. Exosomes derived from HPV E6 overexpressed (HPV E6+) cervical squamous cell carcinoma (CESC) cells were found to induce the polarisation of macrophages towards M2 type. Specifically, miR-204-5p, enriched in HPV E6 + CESC exosomes, was transported into macrophages and triggered M2 macrophage polarisation by inhibiting JAK2. The clinical relevance of exosomal miR-204-5p in the progression of cervical lesions was validated through serum samples from 35 cases. Exosomal miR-204-5p emerges as a critical factor influencing M2 macrophage polarisation and is correlated with the severity of cervical lesions. Consequently, miR-204-5p could be used as a potential treatment and a candidate biomarker for cervical lesions.

High M2/M1 Macrophage Ratio Observed in Nasal Polyps Formed in Allergic Fungal Rhinosinusitis.

Allergic fungal rhinosinusitis (AFRS) shares similarities with eosinophilic chronic rhinosinusitis (ECRS), both characterized by intractable nasal polyps. The key distinction lies in the presence of fungal infection within the nasal cavity. While ECRS nasal polyps are known for significant infiltration of M2 macrophages and eosinophils, as well as an increase in high endothelial venule (HEV)-like vessels, these features are less commonly reported in AFRS. This study compared clinicopathological findings between AFRS (n=10), ECRS (n=12), and non-ECRS (n=10) patients' nasal polyps using immunohistochemical analysis for CD163 and CD68 to assess the M2/M1 macrophage ratio, and peripheral lymph node addressin (PNAd) and CD34 to evaluate the proportion of HEV-like vessels. AFRS showed a significantly higher number of CD163-positive M2 macrophages and an increased M2/M1 ratio compared with ECRS. However, the percentage of HEV-like vessels and the number of eosinophils infiltrating the nasal polyps were similar in both AFRS and ECRS. The observed increase in M2 macrophages in AFRS nasal polyps is presumed to be induced by fungal infection in the nasal cavity, in comparison with ECRS. These results highlight the distinctive immunological profiles of AFRS and ECRS, emphasizing the role of macrophage polarization in their pathogenesis.

Inhalation of Microplastics Induces Inflammatory Injuries in Multiple Murine Organs via the Toll-like Receptor Pathway.

Previous studies have detected microplastics (MPs) in human biological samples, such as lungs, alveolar lavage fluid, and thrombus. However, whether MPs induce health effects after inhalation are unclear. In this study, fluorescent polystyrene microplastics (PS-MPs) were found in the thymus, spleen, testes, liver, kidneys, and brain on day 1 or day 3 after one intratracheal instillation. Furthermore, mice showed inflammation in multiple organs, manifested as obvious infiltration of neutrophils and macrophages, increased Toll-like receptors (TLRs), myeloid differentiation primary response protein 88 (MyD88) and nuclear factor-κB (NF-κB), as well as proinflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-1β) in the lungs, thymus, spleen, liver, and kidneys after four intratracheal instillations of PS-MPs at once every 2 weeks. Hepatic and renal function indexes were also increased. Subsequently, the inflammatory response in multiple murine organs was significantly alleviated by TLR2 and TLR4 inhibitors. Unexpectedly, we did not find any elevated secretion of monocyte chemotactic protein (MCP)-1 or TNF-α by RAW264.7 macrophages in vitro. Thus, PS-MPs induced inflammatory injuries in multiple murine organs via the TLRs/MyD88/NF-κB pathway in vivo, but not macrophages in vitro. These results may provide theoretical support for healthy protection against PS-MPs and their environmental risk assessment.

Integrated bioinformatics analysis and experimental validation on malignant progression and immune cell infiltration of LTBP2 in gliomas

BackgroundGliomas are the highly aggressive brain tumor and also the most devastating human tumors. The latent TGF binding proteins (LTBP) had been found to be involved in malignant biological process and could be used as potent biomarkers in several solid tumors. While the role of LTBP family in human glioma remain to be elucidated.MethodsNormalized gene expression and corresponding clinical data of 2407 gliomas samples in public datasets were downloaded from Gliovis. Kaplan–Meier methods and Cox regression analysis was used for survival analyses.Western blot (WB) and Immunohistochemical (IHC) testing were employed to test LTBPs protein level in 154 gliomas samples. Correlation between LTBP2 expression and immune infiltration was evaluated by immunofluorescence (IF) and IHC in glioma tissues. CCK8 and flow cytometric analysis were used to detect the effect of LTBP2 on glioma cells. Orthotopic glioma- mouse models were utilized to evaluate effects in vivo.ResultsLTBP2 mRNA level was dramatically higher in glioma samples compared with non-tumor brain tissues in XENA-TCGA_GTEx, Gill and Gravendeel datasets (all P < 0.01), and its expression positively correlated with glioma WHO grade, IDH1/2 wildtype and mesenchymal subtypes. These results were confirmed by In-house cohort which was detected by WB and IHC. We found that gliomas patients with high LTBP2 level had shorter OS than those with low LTBP2 level. LTBP2 expression significantly associated with glioma immune score (Spearman r = 0.68, P < 0.01)) and strongly correlated with infiltration degreee of macrophages both in lower grade gliomas (LGG) and GBM. Knocking down LTBP2 obviously reduced proliferation and enhanced sensitivity to temozolomide in U87 and U251 cells. Nude mice with lower expression of LTBP2 had slower tumor growth, and accompanied by less tumor-associated macrophages (TAMs) infiltration detected by IHC staining in vivo. Finally, low LTBP2 expression glioma patients who received chemotherapy survived longer than patients with high LTBP2 expression.ConclusionLTBP2 could be used as a prognostic marker, and high LTBP2 expression related to abundant TAMs infiltration and with a worse response to chemotherapy.

NSUN2 knockdown inhibits macrophage infiltration in diabetic nephropathy via reducing N5-methylcytosine methylation of SOCS1.

N5-methylcytosine (m5C) methylation is involved in various disease progression; however, its role in diabetic nephropathy (DN) has not been studied. The aim of this study was to investigate the role of NSUN2 in DN and the underlying mechanism. Streptozotocin-induced experimental mouse model was generated to analyze the role of NSUN2 in vivo, and high glucose (HG)-treated Raw264.7 cells were used to assess the effect of NSUN2 on macrophage infiltration in vitro. The regulation of NSUN2 on SOCS1 m5C methylation was evaluated using m5C methylated RNA immunoprecipitation, luciferase reporter analysis, and RNA stability determination assay. The results indicated that NSUN2 was highly expressed in the blood and kidney of DN mice. Knockdown of NSUN2 alleviated kidney damage, reduced blood glucose and urine albumin, and suppressed macrophage infiltration in DN mice. Moreover, NSUN2 interacted with SOCS1, and silenced NSUN2 inhibited m5C levels of SOCS1 to reduce SOCS1 mRNA stability. Additionally, interference with NSUN2 suppressed macrophage migration, invasion, and infiltration by positively regulating SOCS1 expression under HG conditions. In conclusion, silencing of NSUN2 inhibits macrophage infiltration by reducing m5C modification of SOCS1, and thereby attenuates renal injury. The findings suggest a novel regulatory mechanism between NSUN2-mediated m5C modification and DN.

Complement 3a Receptor 1 on Macrophages and Kupffer cells is not required for the Pathogenesis of Metabolic Dysfunction-Associated Steatotic Liver Disease.

Together with obesity and type 2 diabetes, metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing global epidemic. Activation of the complement system and infiltration of macrophages has been linked to progression of metabolic liver disease. The role of complement receptors in macrophage activation and recruitment in MASLD remains poorly understood. In human and mouse, C3AR1 in the liver is expressed primarily in Kupffer cells, but is downregulated in humans with MASLD compared to obese controls. To test the role of complement 3a receptor (C3aR1) on macrophages and liver resident macrophages in MASLD, we generated mice deficient in C3aR1 on all macrophages (C3aR1-MjKO) or specifically in liver Kupffer cells (C3aR1-KpKO) and subjected them to a model of metabolic steatotic liver disease. We show that macrophages account for the vast majority of C3ar1 expression in the liver. Overall, C3aR1-MjKO and C3aR1-KpKO mice have similar body weight gain without significant alterations in glucose homeostasis, hepatic steatosis and fibrosis, compared to controls on a MASLD-inducing diet. This study demonstrates that C3aR1 deletion in macrophages or Kupffer cells, the predominant liver cell type expressing C3aR1 , has no significant effect on liver steatosis, inflammation or fibrosis in a dietary MASLD model.

Inhibition of TREM-1 ameliorates angiotensin II-induced atrial fibrillation by attenuating macrophage infiltration and inflammation through the PI3K/AKT/FoxO3a signaling pathway

Inflammation and infiltration of immune cells are intricately linked to the pathogenesis of atrial fibrillation (AF). Triggering receptor expressed on myeloid cells-1 (TREM-1), an enhancer of inflammation, is implicated in various cardiovascular disorders. However, the precise role and potential mechanisms of TREM-1 in the development of AF remain ambiguous. Atrial samples from patients with AF were used to assess the expression levels of TREM-1. An angiotensin II (Ang II)-induced AF mouse model was established to assess the functionality of TREM-1. Cardiac function and AF inducibility were assessed through echocardiography, programmed transvenous cardiac pacing, and atrial electrophysiological mapping. Peripheral blood and atrial inflammatory cells were assessed using flow cytometry. Using histology, bulk RNA sequencing, biochemical analyses, and cell cultures, the mechanistic role of TREM-1 in AF was elucidated. TREM-1 expression was upregulated and co-localized with macrophages in the atria of patients with AF. Pharmacological inhibition of TREM-1 decreased Ang II-induced atrial enlargement and electrical remodeling. TREM-1 inhibition also ameliorated Ang II-induced NLRP3 inflammasome activation, inflammatory factor release, atrial fibrosis, and macrophage infiltration. Transcriptomic analysis revealed that TREM-1 modulates Ang II-induced inflammation through the PI3K/AKT/FoxO3a signaling pathway. In vitro studies further supported these findings, demonstrating that TREM-1 activation exacerbates Ang II-induced inflammation, while overexpression of FoxO3a counteracts this effect. This study discovered the critical role of TREM-1 in the pathogenesis of AF and its underlying molecular mechanisms. Inhibition of TREM-1 provides a new therapeutic strategy for the treatment of AF.

Inhibition of HDAC6 mitigates high-fat diet-induced kidney inflammation and hypertension via reduced infiltration of macrophages

Obesity-mediated hypertension is a worldwide problem. Recent research has indicated that chronic inflammation is associated with the pathogenesis of obese hypertension. Activated immune cells infiltrate target organs, such as arteries, kidneys, and brain, causing end-organ damage and hypertension. Histone deacetylase 6 (HDAC6) regulates the inflammatory cell activity mediating the production of inflammatory cytokines and may play a role in the crosstalk between inflammation and hypertension. In this study, we investigated the roles of HDAC6 in high-fat diet (HFD)-induced kidney inflammation and hypertension. Nine-week-old male C57BL/6 mice were fed either a normal diet (ND) or HFD for 15 weeks. HFD-induced hypertension with increased HDAC6 activities in the kidney and bone marrow-derived macrophages (BMDM). When HFD group reached the hypertensive phase, each group of mice was intraperitoneally injected with vehicle or selective HDAC6 inhibitor Tubacin (1 mg/kg/day) for 14 days. Tubacin treatment lowered blood pressure (BP) of HFD-fed mice to the normal level with successful inhibition of HDAC6 activity. Immunohistochemical staining of F4/80, which is known as a macrophage marker, revealed that HFD promoted macrophage infiltration into the kidney. Consequently, pro-inflammatory factors TNFα and IL-6 gene expressions in the kidney were increased by HFD. Tubacin canceled HFD-induced macrophage infiltration and inflammation in the kidney. HDAC6 gene silencing and Tubacin treatment in Raw 264.7 cells also blocked the chemoattractant-stimulated cell migration in vitro. The results reveal the novel role of HDAC6 in BMDM migration, kidney inflammation, and high BP induced by HFD providing HDAC6 inhibitors as a therapeutic option for obesity-mediated hypertension.

Unveiling the role of CXCL8/CXCR2 in intervertebral disc degeneration: A path to promising therapeutic strategies

BackgroundIntervertebral disc degeneration(IVDD) is the primary etiology of low back pain and radicular pain. Recent studies have found that chemokines play a role in IVDD, but the underlying mechanism is largely unclear. MethodsBioinformatics analysis was employed to screen CXCL8 as the target gene. The expression levels of CXCL8 and CXCR2 were quantified using RT-qPCR, western blot(WB), immunohistochemistry(IHC), and enzyme-linked immuno-sorbent assay(ELISA). In the IVDD mouse model, X-ray images, Safranin O-fast green staining(SO-FG), IHC, and WB were conducted to assess the therapeutic effects of CXCL8 on IVDD. Reactive oxygen species (ROS) production, apoptosis of nucleus pulposus cells (NPCs), and the involvement of the NF-κB pathway were evaluated through WB, flow cytometry, immunofluorescence(IF), and Tunnel assay. ResultsIn our study, we observed that CXCL8 emerged as one of the chemokines that were up-regulated in IVDD. The mitigation of extracellular matrix degradation (ECM) and the severity of IVDD were significantly achieved by neutralizing CXCL8 or its receptor CXCR2(SB225002, CXCR2 antagonist). The release of CXCL8 from infiltrated macrophages within intervertebral discs (IVDs) was predominantly observed upon stimulation. CXCL8 exerted its effects on NPCs by inducing apoptosis and ECM degradation through the activation of CXCR2. Specifically, the formation of the CXCL8/CXCR2 complex triggered the NF-κB signaling pathway, resulting in an abnormal increase in intracellular ROS levels and ultimately contributing to the development of IVDD. ConclusionOur findings suggest that macrophage-derived CXCL8 and subsequent CXCR2 signaling play crucial roles in mediating inflammation, oxidative stress, and apoptosis in IVDD. Targeting the CXCL8/CXCR2 axis may offer promising therapeutic strategies to ameliorate IVDD. The translational potential of this articleThis study indicates that CXCL8 can effectively exacerbate the excessive apoptosis and oxidative stress of NPCs through activating the NF-κB pathway. This study may provide new potential targets for preventing and reversing IVDD.

PD-L1+ Lymphocytes Are Associated with CD4+, Foxp3+CD4+, IL17+CD4+ T Cells and Subtypes of Macrophages in Resected Early-Stage Non-Small Cell Lung Cancer.

The non-canonical PD-L1 pathway revealed that programmed-death ligand 1 (PD-L1) expression in immune cells also plays a crucial role in immune response. Moreover, immune cell distribution in a tumour microenvironment (TME) is pivotal for tumour genesis. However, the results remain controversial and further research is needed. Distribution of PD-L1-positive (PD-L1+) tumour-infiltrating lymphocytes in the context of TME was assessed in 72 archival I-III stage surgically resected NSCLC tumour specimens. Predominant PD-L1+ lymphocyte distribution in the tumour stroma, compared to islets, was found (p = 0.01). Higher PD-L1+ lymphocyte infiltration was detected in smokers due to their predominance in the stroma. High PD-L1+ lymphocyte infiltration in tumour stroma was more common in tumours with higher CD4+ T cell infiltration in islets and stroma, Foxp3+CD4+ T cell infiltration in islets and lover M1 macrophage infiltration in the stroma (p = 0.034, p = 0.034, p = 0.005 and p = 0.034 respectively). Meanwhile, high PD-L1+ lymphocyte infiltration in islets was predominantly found in tumours with high levels of IL-17A+CD4+ T cells in islets and Foxp3+CD4+ T cells in islets and stroma (p = 0.032, p = 0.009 and p = 0.034, respectively). Significant correlations between PD-L1+ lymphocytes and tumour-infiltrating CD4+, Foxp3+CD4+, IL-17A+CD4+ T cells and M2 macrophages were found. An analysis of the tumour-immune phenotype revealed a significant association between PD-L1 expression and IL17+CD4+ and Foxp3+CD4+ immune phenotypes. PD-L1+ lymphocytes are associated with the distribution of CD4+, Foxp3+CD4+, IL17A+CD4+ T cells, M1 and M2 macrophages in TME of resected NSCLC.

Optimized administration of human embryonic stem cell-derived immunity-and-matrix regulatory cells for mouse lung injury and fibrosis

BackgroundLung injury and pulmonary fibrosis (PF), frequently arising as sequelae of severe and acute lung disease, currently face a dearth of effective therapeutic potions. Mesenchymal stem cells (MSCs) with immunomodulatory and tissue repair functions have immense potential to treat lung injury and PF. However, the optimal route of administration, timing, and frequency of dosing remain elusive. Human embryonic stem cell-derived immunity-and-matrix-regulatory cells (IMRCs) have shown therapeutic potential for lung injury and PF.MethodsTo ascertain the optimal therapeutic regimen for IMRCs in PF, we conducted an experimental study. Utilizing a mouse model of PF induced by bleomycin (BLM), IMRCs were administered via either a single or double intravenous (IV) or intratracheal (IT) injection on the first and seventh days post-BLM induction.ResultsOur findings revealed that IV infusion of IMRCs surpassed IT infusion in enhancing survival rates, facilitating body weight recovery, and optimizing Ashcroft and Szapiel scores among the model mice. Notably, IV administration exhibited a more profound ability to mitigate lung inflammation and fibrosis. Moreover, earlier and more frequent administrations of IMRCs were found to be advantageous in enhancing their therapeutic effects. Specifically, early administration with two IV infusions significantly improved body weight, lung organ coefficient, pulmonary ventilation and diffusion functions, and PF. This was accompanied by an increase in alveolar type I and II epithelial cells and a suppression of macrophage infiltration via CD24.ConclusionCollectively, these results suggested that IMRCs infusion ameliorated lung injury by promoting lung regeneration and inhibiting macrophage infiltration in a route, time, and frequency-dependent manner.

An injectable self-lubricating supramolecular polymer hydrogel loaded with platelet lysate to boost osteoarthritis treatment

Globally, osteoarthritis (OA) is the most prevalent joint disease and is characterized by infiltration of M1 macrophages in the synovium, anabolic–catabolic imbalance of the extracellular matrix (ECM), increased articular shear force and overproduction of reactive oxygen species (ROS). Disease-modifying OA drugs are not yet available, and treatments for OA focus solely on reducing pain and inflammation and have limited therapeutic effect. Herein, we developed an injectable self-lubricating poly(N-acryloyl alaninamide) (PNAAA) hydrogel loaded with platelet lysate (PL) (termed “PNAAA@PL”) for treating OA. Tribological and drug release tests revealed suitable lubrication properties and sustained release of bioactive factors in PNAAA@PL. In vitro experiments showed that PNAAA@PL alleviated interleukin-1β (IL-1β)-induced anabolic–catabolic imbalance of chondrocytes and repolarized pro-inflammatory M1 macrophages to the anti-inflammatory M2 phenotype via intracellular ROS scavenging. Additionally, the PNAAA@PL hydrogel enhanced the migratory capacity and chemotaxis ability of stem cells, which are essential for chondrogenesis. In vivo, the functionalized PNAAA@PL hydrogel acted like synovial fluid following intra-articular injection into a rat OA model with anterior cruciate ligament transection, ultimately attenuating cartilage degeneration and synovitis. According to molecular mechanism studies, PNAAA@PL repairs cartilage in the OA model by inhibiting the NF-ĸB pathway. Overall, this self-lubricating PNAAA@PL hydrogel offers a comprehensive strategy for preventing OA progression by engineering a biophysiochemical microenvironment to generate high-quality hyaline cartilage.

Macrophage polarization and macrophage-related factor expression in hypertrophy of the ligamentum flavum.

Owing to the unknow types of infiltrating macrophages and the corresponded factors, we aimed to investigate the specific types of infiltrating macrophages involved in HLF and the expression of macrophage-related factors. The ligamentum flavum was obtained from patients with lumbar spinal stenosis (HLF group; n = 15) and lumbar disc herniation (non-hypertrophic ligamentum flavum [NLF] group; n = 15). Ligamentum flavum specimens were paraffin embedded, followed by histological and immunohistochemical staining to identify the macrophage type and expression of macrophage-related factors. The HLF group demonstrated CD206 marker expression, while the NLF group did not (P < 0.0001; n = 11). CD68 marker was expressed in both groups (P > 0.05; n = 11). CCR7 was not expressed in either group. The expression levels of the extracellular matrix proteins aggrecan (Agg), type I collagen (Coll1), and type II collagen (Coll2) were higher in the HLF group than in the NLF group (P < 0.0001; n = 11). The aging markers p21, p16, and p53 were expressed in the HLF group, but not in the NLF group (P < 0.0001; n = 11). The expression levels of the inflammatory factors TNF-α and IL-1β were higher in the HLF group than in the NLF group (P < 0.0001; n = 11). Similarly, the expression level of the fibrosis factor TGF-β1 was higher in the HLF group than in the NLF group (P < 0.0001; n = 11). The infiltration of M2 macrophages may be involved in HLF, while involvement of M1 macrophages may only occur early in inflammation. The expression of extracellular matrix proteins and macrophage-related factors was increased. Aging may also be associated with HLF.

ITGA5 is associated with prognosis marker and immunosuppression in head and neck squamous cell carcinoma

BackgroundHead and neck squamous cell carcinoma (HNSCC) is a major tumor that seriously threatens the health of the head and neck or mucosal system. It is manifested as a malignant phenotype of high metastasis and invasion caused by squamous cell transformation in the tissue area. Therefore, it is necessary to search for a biomarker that can systematically correlate and reflect the prognosis of HNSCC based on the characteristics of head and neck tumors.MethodsBased on TCGA-HNSCC data, R software was used to analyze gene expression, correlation, Venn diagram, immune invasive and immunosuppressive phenotypes respectively. The intrinsic effect of ITGA5 on the malignant phenotype of HNSCC cells was verified by cell experiments. Immunohistochemical images from The Human Protein Atlas (THPA) database display the differences in the expression of related proteins in HNSCC tissues. Based on functional enrichment and correlation analysis, the prognostic value of ITGA5 for HNSCC was explored, and the expression level of ITGA5 may affect the chemotherapy of targeting the PI3K-AKT.ResultsIn this study, the target gene ITGA5 may be identified as a valuable prognostic marker for HNSCC. The results of enrichment analysis showed that ITGA5 was mainly involved in the dynamic process of extracellular matrix, which may affect the migration or metastasis of tumor cells. Meanwhile, ITGA5 may be closely related to the infiltration of M2 macrophages, and its secretory phenotypes TGFB1, PDGFA and PDGFB may affect the immunosuppressive phenotypes of tumor cells, which reflects the systemic influence of ITGA5 in HNSCC. In addition, the expression levels of ITGA5 were negatively correlated with the efficacy of targeting PI3K-AKT chemotherapy.ConclusionITGA5 can be used as a potential marker to systematically associate with prognosis of HNSCC, which may be associated with HNSCC malignant phenotype, immunosuppression and chemotherapy resistance.