Steroid-induced osteonecrosis of the femoral head (SONFH) is avascular necrosis of the femoral head caused by long-erm use of corticosteroids, and its pathogenesis is complex and affected by changes in the dynamic balance of the bone microenvironment. With the deepening of research, the role of bone microenvironment in the pathogenesis of SONFH has been gradually revealed. In the case of excessive use of glucocorticoids (GCs), the bone microenvironment changes significantly, causing imbalance in bone lipid metabolism, microcirculation disorders and disorders of immune regulation, which promotes the increase of the number and activity of osteoclasts, and interferes with the differentiation of osteoblasts and adipoblasts. Through the regulation of PI3K/AKT, OPG/RANKL/RANK, MAPK, JAK/STAT, Hedgehog and other signaling pathways, it eventually leads to osteocyte apoptosis, bone microvascular rupture and destruction of trabecular bone structure, which in turn leads to osteonecrosis, bone density reduction and bone microstructure destruction due to bone microcirculation ischemia, and finally leads to necrosis of the femoral head. This article reviews the role of bone microenvironment homeostasis in GCs-induced ONFH and the regulatory mechanism of bone microenvironment, which is helpful to reveal the pathogenesis of SONFH and provide a theoretical basis for exploring effective intervention strategies.
Humans ; Femur Head Necrosis/physiopathology* ; Animals ; Signal Transduction ; Bone and Bones/metabolism* ; Glucocorticoids/adverse effects* ; Cellular Microenvironment

In the ever-evolving landscape of cancer therapy, while cancer treatments such as chemotherapy, radiotherapy, and targeted therapy aim to eradicate malignant cells, they also inadvertently trigger cellular senescence in both cancerous and microenvironmental tissues. Therapy-induced senescence (TIS) can act as a barrier against tumor growth by halting cell proliferation in the short term, but the long-term persistence of therapy-induced senescent (TISnt) cells may pose a significant challenge in cancer management. Their distinct characteristics, like senescence-associated secretory phenotype (SASP), metabolic dysregulation, and immune evasion, make them exhibit remarkable heterogeneity to orchestrate the tumor microenvironment (TME), resulting in therapy resistance. However, how these TISnt cells functioning differently in cancer progression, and the intricate mechanisms by which they remodel the senescence-associated immunosuppressive microenvironment present challenges for improving anticancer therapy. Therefore, this review summarizes the heterogeneous TISnt cell phenotypes contributing to an accumulated senescent state, outlines their multidimensional interactions in the senescent microenvironment, and discusses current senescence-targeting strategies. Building on the current understanding of TIS, we propose potential avenues for improving TIS-targeting methodologies in the context of head and neck cancer, a representative heterogeneous malignancy, which can substantially enhance the efficacy of the "one-two punch" sequential treatment approach for head and neck cancer.
Humans ; Cellular Senescence/drug effects* ; Tumor Microenvironment ; Neoplasms/pathology* ; Senescence-Associated Secretory Phenotype

Spinal cord injury (SCI) represents a complex pathophysiological process involving the interaction of multiple cell types. Conventional sequencing methods can only detect the average gene expression level of the damaged local cell populations, which is difficult to reflect its heterogeneity. Therefore, new technologies are needed to reveal the intercellular heterogeneity and the complex intercellular interactions of the damaged lesions. The single-cell RNA sequencing (scRNA-seq) technique facilitates high-resolution profiling of gene expression at the single-cell level, providing insights into cellular heterogeneity and function, potential molecular pathways, cell fate transitions, and the intercellular interactions pertinent to disease progression. This technology generates valuable gene expression data that support both basic and translational research efforts aiming at the identification of therapeutic targets for intervention. The scRNA-seq technique and its multifaceted application in the local immune microenvironment of injury after SCI were discussed, which will contribute to a more comprehensive understanding of the pathophysiological processes in the immune microenvironment of SCI.
Spinal Cord Injuries/genetics* ; Humans ; Single-Cell Analysis/methods* ; Sequence Analysis, RNA/methods* ; Animals ; Gene Expression Profiling/methods* ; Cellular Microenvironment/genetics*

BACKGROUND: One of the most important treatment modalities for non-small cell lung cancer (NSCLC) is immune checkpoint inhibitor. Nevertheless, a small percentage of patients do not respond well to these therapies, highlighting the significance of identifying important CD8+ T cell subsets for immunotherapy and creating trustworthy biomarkers. The purpose of this study is to assess the potential utility of TIM3+CD8+ T cells as new biomarkers by examining their expressions in various areas of the NSCLC tumor microenvironment. METHODS: Based on biopsy techniques, tumor tissue samples were obtained from patients with NSCLC and categorized into tumor central and non-central regions. Using flow cytometry, the infiltration of TIM3+CD8+ T cells and the surface expression of programmed cell death 1 (PD-1) on these cells were examined, and their correlations with the effectiveness of immunotherapy were assessed. RESULTS: The non-central region of tumor tissues had considerably larger infiltration of TIM3+CD8+ T lymphocytes compared to the non-central region (P<0.0001). This pattern was found in both subgroups with tumor diameters ≥3 cm or <3 cm (P<0.01). In comparison to TIM3-CD8+ T cells, TIM3+CD8+ T cells showed higher levels of PD-1 (P<0.001), with more PD-1+TIM3+CD8+ T cells invading the non-central region (P<0.01). Clinical responders to immunotherapy had considerably lower infiltration levels of TIM3+CD8+ T cells in the tumor non-central region compared to non-responders, with lower levels correlated with better clinical outcomes (P<0.01), while no correlation was identified in the tumor central region (P>0.05). According to reciever operating characteristic (ROC) curve analysis, TIM3+CD8+ T cells in the tumor non-central region had an area under the curve (AUC) of 0.9375 for predicting the effectiveness of immunotherapy, which was considerably higher than that of TIM3+CD8+ T cells in the tumor central region and programmed cell death ligand 1 (PD-L1) [tumor proportion score (TPS)]. CONCLUSIONS In the tumor microenvironment of NSCLC, TIM3+CD8+ T cells show regional distribution patterns. The expression of this cell population in the non-central region of the tumor microenvironment may be a biomarker for predicting the effectiveness of immunotherapy.
Humans ; Carcinoma, Non-Small-Cell Lung/metabolism* ; Lung Neoplasms/metabolism* ; Hepatitis A Virus Cellular Receptor 2/immunology* ; Tumor Microenvironment/immunology* ; CD8-Positive T-Lymphocytes/metabolism* ; Male ; Female ; Middle Aged ; Aged ; Adult ; Programmed Cell Death 1 Receptor/metabolism* ; Immunotherapy ; Clinical Relevance

Given its state of stable proliferative inhibition, cellular senescence is primarily depicted as a critical mechanism by which organisms delay the progression of carcinogenesis. Cells undergoing senescence are often associated with the alteration of a series of specific features and functions, such as metabolic shifts, stemness induction, and microenvironment remodeling. However, recent research has revealed more complexity associated with senescence, including adverse effects on both physiological and pathological processes. How organisms evade these harmful consequences and survive has become an urgent research issue. Several therapeutic strategies targeting senescence, including senolytics, senomorphics, immunotherapy, and function restoration, have achieved initial success in certain scenarios. In this review, we describe in detail the characteristic changes associated with cellular senescence and summarize currently available countermeasures.
Humans ; Cellular Senescence ; Carcinogenesis ; Immunotherapy ; Aging ; Tumor Microenvironment

Since the airways are constantly exposed to various pathogens and foreign antigens, various kinds of cells in the airways—including structural cells and immune cells—interact to form a precise defense system against pathogens and antigens that involve both innate immunity and acquired immunity. Accumulating evidence suggests that innate lymphoid cells (ILCs) play critical roles in the maintenance of tissue homeostasis, defense against pathogens and the pathogenesis of inflammatory diseases, especially at body surface mucosal sites such as the airways. ILCs are activated mainly by cytokines, lipid mediators and neuropeptides that are produced by surrounding cells, and they produce large amounts of cytokines that result in inflammation. In addition, ILCs can change their phenotype in response to stimuli from surrounding cells, which enables them to respond promptly to microenvironmental changes. ILCs exhibit substantial heterogeneity, with different phenotypes and functions depending on the organ and type of inflammation, presumably because of differences in microenvironments. Thus, ILCs may be a sensitive detector of microenvironmental changes, and analysis of their phenotype and function at local sites may enable us to better understand the microenvironment in airway diseases. In this review, we aimed to identify molecules that either positively or negatively influence the function and/or plasticity of ILCs and the sources of the molecules in the airways in order to examine the pathophysiology of airway inflammatory diseases and facilitate the issues to be solved.
Adaptive Immunity ; Cellular Microenvironment ; Cytokines ; Homeostasis ; Immunity, Innate ; Inflammation ; Lymphocytes ; Neuropeptides ; Phenotype ; Plastics ; Population Characteristics ; Respiratory Tract Diseases

Idiopathic pulmonary fibrosis(IPF)is a progressive lung disease characterized by pulmonary interstitial fibrosis and pulmonary dysfunction.Cell microenvironment is mainly composed of cell components,extracellular matrix,extracellular regulators,and liquid substances.Changes in microenvironment components are closely related to IPF.This article elaborates the roles of cell microenvironments including cytokines,mesenchymal cells,extracellular matrix,and unfolded proteins in the pathogenesis of IPF.
Cellular Microenvironment ; Extracellular Matrix ; Humans ; Idiopathic Pulmonary Fibrosis ; Lung

In this paper, we review the results of previous studies and summarize the effects of various factors on the regulation of bone metabolism in traumatic bone infections. Infection-related bone destruction incorporates pathogens and iatrogenic factors in the process of bone resorption dominated by the skeletal and immune systems. The development of bone immunology has established a bridge of communication between the skeletal system and the immune system. Exploring the effects of pathogens, skeletal systems, immune systems, and antibacterials on bone repair in infectious conditions can help improve the treatment of these diseases.
Anti-Bacterial Agents/administration & dosage* ; Bone and Bones/metabolism* ; Cellular Microenvironment ; Humans ; Immune System/immunology* ; Lymphocyte Subsets/immunology* ; Osteitis/microbiology* ; Osteoblasts/physiology* ; Osteoclasts/physiology* ; Staphylococcal Infections

Cerebral pericytes are perivascular cells that stabilize blood vessels. Little is known about the plasticity of pericytes in the adult brain in vivo. Recently, using state-of-the-art technologies, including two-photon microscopy in combination with sophisticated Cre/loxP in vivo tracing techniques, a novel role of pericytes was revealed in vascular remodeling in the adult brain. Strikingly, after pericyte ablation, neighboring pericytes expand their processes and prevent vascular dilatation. This new knowledge provides insights into pericyte plasticity in the adult brain.
Animals ; Brain ; blood supply ; physiology ; physiopathology ; Brain Diseases ; physiopathology ; Capillaries ; physiology ; Cellular Microenvironment ; Diabetic Retinopathy ; physiopathology ; Endothelial Cells ; physiology ; Humans ; Pericytes ; physiology ; Vascular Remodeling

BACKGROUND: Polymeric hydrogels are extensively used as promising biomaterials in a broad range of biomedical applications, including tissue engineering, regenerative medicine, and drug delivery. These materials have advantages such as structural similarity to the native extracellular matrix (ECM), multi-tunable physicochemical and biological properties, and biocompatibility. METHODS: In situ forming hydrogels show a phase transition from a solution to a gel state through various physical and chemical cross-linking reactions. These advanced hydrogel materials have been widely used for tissue regenerative medicine because of the ease of encapsulating therapeutic agents, such as cells, drugs, proteins, and genes. RESULTS: With advances in biomaterials engineering, these hydrogel materials have been utilized as either artificial cellular microenvironments to create engineered tissue constructs or as bioactive acellular matrices to stimulate the native ECM for enhanced tissue regeneration and restoration. CONCLUSION: In this review, we discuss the use of in situ cross-linkable hydrogels in tissue engineering and regenerative medicine applications. In particular, we focus on emerging technologies as a powerful therapeutic tool for tissue regenerative medicine applications.
Biocompatible Materials ; Cellular Microenvironment ; Extracellular Matrix ; Hydrogel* ; Hydrogels* ; Phase Transition ; Polymers ; Regeneration ; Regenerative Medicine* ; Tissue Engineering