The changes and correlation of IL-6 and oxidative stress levels in RAW264.7 macrophage cells induced by PAHs in PM2.5.

The objective of this study was to investigate the effects of anthracene (Ant) with 3 rings, benzo[a]anthracene (BaA) with 4 rings and benzo[b]fluoranthene (BbF) with 5 rings in fine particulate matter (PM2.5) at different exposure times (4 h and 24 h) and low exposure levels (0 pg/mL, 0.1 pg/mL, 1 pg/mL, 100 pg/mL and 10,000 pg/mL) on RAW264.7 cells. The changes of interleukin-6 (IL-6) and oxidative stress levels in RAW264.7 cells were investigated by methyl-thiazolyl-tetrazolium (MTT) and enzyme-linked immunosorbent assay (ELISA). Pearson correlation analysis was used to analyze the correlation between variables. Ant, BaA and BbF induced the secretion of IL-6 and the occurrence of oxidative stress in RAW264.7 cells. The inflammatory effect and oxidative damage were exacerbated with prolonged exposure time, increasing exposure concentration and increasing number of PAH rings. At the same time, IL-6 was found to have a certain correlation with the levels of ROS, MDA and SOD. Exposure to atmospheric PAHs at low concentrations can also produce toxic effects on cells, IL-6 and oxidative stress work together in cell damage. The study is expected to provide a theoretical and experimental basis for air pollution control and human health promotion.

Application of a genetically engineered macrophage cell line for evaluating cellular effects of UV/US-treated poly(ethylene terephthalate) microplastics.

Microplastic (MP) pollution is a global environmental problem. To understand the biological effects of MPs on humans, it is essential to evaluate the response of human cells to model plastic particles that mimic environmental MPs in a sensitive and non-invasive manner. In this study, we investigated the preparation of poly(ethylene terephthalate) (PET) fragments with properties similar to those of environmental MPs by combining photo-oxidative degradation via ultraviolet (UV) irradiation with mechanical pulverization and hydrolysis via ultrasound (US) exposure. Combination of UV and US treatments decreased the particle size of PET fragments to 10.2 µm and increased their crystallinity and Young's modulus to 35.7 % and 0.73 GPa, respectively, while untreated PET fragments showed the particle size of 18.9 µm, the crystallinity of 33.7 %, and Young's modulus of 0.48 GPa. In addition, an increase in negative surface potential and O/C ratio were observed for UV/US-treated PET fragments, suggesting surface oxidation via UV/US treatment. Cytokine secretion from human macrophages was evaluated by a highly sensitive inflammation evaluation system using the HiBiT-based chemiluminescence detection method developed by genome editing technology. UV/US-treated PET fragments induced a 1.4 times higher level of inflammatory cytokine secretion on inflammatory macrophages than untreated ones, suggesting that the biological responses of PET fragments could be influenced by changes in material properties via oxidation. In conclusion, UV/US treatment enables efficient preparation of model plastic particles and is expected to provide new insights into the evaluation of biological effects using human cells. (240 words).

4,4'-Methylene diphenyl diisocyanate exposure induces expression of alternatively activated macrophage-associated markers and chemokines partially through Krüppel-like factor 4 mediated signaling in macrophages.

Occupational exposure to the most widely used monomeric diisocyanate (dNCO), 4,4'-methylene diphenyl diisocyanate (MDI), may lead to the development of occupational asthma (OA). Alveolar macrophages with alternatively activated (M2) phenotype have been implicated in allergic airway responses and the pathogenesis of asthma. Recent in vivo studies demonstrate that M2 macrophage-associated markers and chemokines are induced by MDI-exposure, however, the underlying molecular mechanism(s) by which this proceeds is unclear.Following MDI exposure (in vivo and in vitro) M2 macrophage-associated transcription factors (TFs), markers, and chemokines were determined by RT-qPCR, western blots, and ELISA.Expression of M2 macrophage-associated TFs and markers including Klf4/KLF4, Cd206/CD206, Tgm2/TGM2, Ccl17/CCL17, Ccl22/CCL22, and CCL24 were induced by MDI/MDI-GSH exposure in bronchoalveolar lavage cells (BALCs)/THP-1 macrophages. The expression of CD206, TGM2, CCL17, CCL22, and CCL24 are upregulated by 3.83-, 7.69-, 6.22-, 6.08-, and 1.90-fold in KLF4-overexpressed macrophages, respectively. Endogenous CD206 and TGM2 were downregulated by 1.65-5.17-fold, and 1.15-1.78-fold, whereas CCL17, CCL22, and CCL24 remain unchanged in KLF4-knockdown macrophages. Finally, MDI-glutathione (GSH) conjugate-treated macrophages show increased chemotactic ability to T-cells and eosinophils, which may be attenuated by KLF4 knockdown.Our data suggest that MDI exposure may induce M2 macrophage-associated markers partially through induction of KLF4.

Titanium Particles Modulate Lymphocyte and Macrophage Polarization in Peri-Implant Gingival Tissues.

Titanium dental implants are one of the modalities to replace missing teeth. The release of titanium particles from the implant's surface may modulate the immune cells, resulting in implant failure. However, little is known about the immune microenvironment that plays a role in peri-implant inflammation as a consequence of titanium particles. In this study, the peri-implant gingival tissues were collected from patients with failed implants, successful implants and no implants, and then a whole transcriptome analysis was performed. The gene set enrichment analysis confirmed that macrophage M1/M2 polarization and lymphocyte proliferation were differentially expressed between the study groups. The functional clustering and pathway analysis of the differentially expressed genes between the failed implants and successful implants versus no implants revealed that the immune response pathways were the most common in both comparisons, implying the critical role of infiltrating immune cells in the peri-implant tissues. The H&E and IHC staining confirmed the presence of titanium particles and immune cells in the tissue samples, with an increase in the infiltration of lymphocytes and macrophages in the failed implant samples. The in vitro validation showed a significant increase in the level of IL-1ß, IL-8 and IL-18 expression by macrophages. Our findings showed evidence that titanium particles modulate lymphocyte and macrophage polarization in peri-implant gingival tissues, which can help in the understanding of the imbalance in osteoblast-osteoclast activity and failure of dental implant osseointegration.

PyCoCa:A quantifying tool of carbon content in airway macrophage for assessment the internal dose of particles.

Given the lack of a comprehensive understanding of the complex metabolism and variable exposure environment, carbon particles in macrophages have become a potentially valuable biomarker to assess the exposure level of atmospheric particles, such as black carbon. However, the tedious and subjective quantification method limits the application of carbon particles as a valid biomarker. Aiming to obtain an accurate carbon particles quantification method, the deep learning and binarization algorithm were implemented to develop a quantitative tool for carbon content in airway macrophage (CCAM), named PyCoCa. Two types of macrophages, normal and foamy appearance, were applied for the development of PyCoCa. In comparison with the traditional methods, PyCoCa significantly improves the identification efficiency for over 100 times. Consistency assessment with the gold standard revealed that PyCoCa exhibits outstanding prediction ability with the Interclass Correlation Coefficient (ICC) values of over 0.80. And a proper fresh dye will enhance the performance of PyCoCa (ICC = 0.89). Subsequent sensitivity analysis confirmed an excellent performance regarding accuracy and robustness of PyCoCa under high/low exposure environments (sensitivity > 0.80). Furthermore, a successful application of our quantitative tool in cohort studies indicates that carbon particles induce macrophage foaming and the foaming decrease the carbon particles internalization in reverse. Our present study provides a robust and efficient tool to accurately quantify the carbon particles loading in macrophage for exposure assessment.

Functionalized Macrophage Exosomes with Panobinostat and PPM1D-siRNA for Diffuse Intrinsic Pontine Gliomas Therapy.

Diffuse intrinsic pontine glioma (DIPG) is a rare and fatal pediatric brain tumor. Mutation of p53-induced protein phosphatase 1 (PPM1D) in DIPG cells promotes tumor cell proliferation, and inhibition of PPM1D expression in DIPG cells with PPM1D mutation effectively reduces the proliferation activity of tumor cells. Panobinostat effectively kills DIPG tumor cells, but its systemic toxicity and low blood-brain barrier (BBB) permeability limits its application. In this paper, a nano drug delivery system based on functionalized macrophage exosomes with panobinostat and PPM1D-siRNA for targeted therapy of DIPG with PPM1D mutation is prepared. The nano drug delivery system has higher drug delivery efficiency and better therapeutic effect than free drugs. In vivo and in vitro experimental results show that the nano drug delivery system can deliver panobinostat and siRNA across the BBB and achieve a targeted killing effect of DIPG tumor cells, resulting in the prolonged survival of orthotopic DIPG mice. This study provides new ideas for the delivery of small molecule drugs and gene drugs for DIPG therapy.

Plasma Donor-Derived Cell-Free DNA Levels Are Associated With the Inflammatory Burden and Macrophage Extracellular Trap Activity in Renal Allografts.

Recent studies have confirmed the role of plasma donor-derived cell-free DNA (ddcfDNA) as a reliable non-invasive biomarker for allograft injury after kidney transplantation. Whereas the variability of plasma ddcfDNA levels among recipients has limited their clinical use. This study aimed to explore the intrinsic factors associated with plasma ddcfDNA elevation by investigating the impact of Banff lesions and inflammatory infiltrates on ddcfDNA levels in kidney transplant recipients. From March 2017 to September 2019, a total of 106 kidney transplant recipients with matched allograft biopsies were included, consisting of 13 recipients with normal/nonspecific changes, 13 recipients with borderline changes, 60 with T cell-mediated rejection, and 20 with antibody-mediated rejection. Histologic classification was performed according to the Banff 2017 criteria by two experienced pathologists. Plasma ddcfDNA fractions ranged from 0.12% to 10.22%, with a median level of 0.91%. Banff histology subelements including glomerulitis, intimal arteritis, and severe interstitial inflammation were correlated with increased plasma ddcfDNA levels. The inflammatory cell infiltrate in the allografts was phenotyped by immunochemistry and automatically counted by digital image recognition. Pearson correlation analysis revealed a significant positive correlation between macrophage infiltrations in allografts and plasma ddcfDNA levels. Additionally, macrophage extracellular trap (MET) activity was significantly associated with the rise in plasma ddcfDNA levels. Our findings demonstrated that plasma ddcfDNA could reflect the inflammatory state in renal allografts and suggested the potential role of METs in the pathogenesis of allograft injury.

Interactions of Nanoparticles with Macrophages and Feasibility of Drug Delivery for Asthma.

Understanding the interaction between nanoparticles and immune cells is essential for the evaluation of nanotoxicity and development of nanomedicines. However, to date, there is little data on the membrane microstructure and biochemical changes in nanoparticle-loaded immune cells. In this study, we observed the microstructure of nanoparticle-loaded macrophages and changes in lipid droplets using holotomography analysis. Quantitatively analyzing the refractive index distribution of nanoparticle-loaded macrophages, we identified the interactions between nanoparticles and macrophages. The results showed that, when nanoparticles were phagocytized by macrophages, the number of lipid droplets and cell volume increased. The volume and mass of the lipid droplets slightly increased, owing to the absorption of nanoparticles. Meanwhile, the number of lipid droplets increased more conspicuously than the other factors. Furthermore, alveolar macrophages are involved in the development and progression of asthma. Studies have shown that macrophages play an essential role in the maintenance of asthma-related inflammation and tissue damage, suggesting that macrophage cells may be applied to asthma target delivery strategies. Therefore, we investigated the target delivery efficiency of gold nanoparticle-loaded macrophages at the biodistribution level, using an ovalbumin-induced asthma mouse model. Normal and severe asthma models were selected to determine the difference in the level of inflammation in the lung. Consequently, macrophages had increased mobility in models of severe asthma, compared to those of normal asthma disease. In this regard, the detection of observable differences in nanoparticle-loaded macrophages may be of primary interest, as an essential endpoint analysis for investigating nanomedical applications and immunotheragnostic strategies.

An array-based nanosensor for detecting cellular responses in macrophages induced by femtomolar levels of pesticides.

Environmental agents can induce cellular responses at concentrations far below the limits of detection for current viability and biomarker-based cell sensing platforms. Hypothesis-free cell sensor platforms can be engineered to maximize sensitivity to phenotypic changes, providing a tool for lowering the threshold for detecting cellular changes. Pesticides are one of the most prevalent sources of chemical exposure due to their use in food and agriculture fields. We report here a FRET-based nanosensor array engineered to maximize responses to changes at cell surfaces after pesticide exposure. This sensor array robustly detected macrophage responses to femtomolar concentrations of common pesticides-orders of magnitude lower concentrations than traditional toxicological and biomarker-based strategies. Significantly, this platform was able to classify these responses by pesticide class, demonstrating the ability to distinguish between changes induced by these different agents. Taken together, hypothesis-free cell surface sensing is a promising tool for detecting the effects of ultra-trace environmental chemicals on human health, as well as detecting threshold responses for use in drug discovery and diagnostics.

Macrophage-Mimic Hollow Mesoporous Fe-Based Nanocatalysts for Self-Amplified Chemodynamic Therapy and Metastasis Inhibition via Tumor Microenvironment Remodeling.

Fe-based nanomaterials with Fenton reaction activity are promising for tumor-specific chemodynamic therapy (CDT). However, most of the nanomaterials suffer from low catalytic efficiency due to its insufficient active site exposure and the relatively high tumor intracellular pH, which greatly impede its clinical application. Herein, macrophage membrane-camouflaged carbonic anhydrase IX inhibitor (CAI)-loaded hollow mesoporous ferric oxide (HMFe) nanocatalysts are designed to remodel the tumor microenvironment with decreased intracellular pH for self-amplified CDT. The HMFe not only serves as a Fenton agent with high active-atom exposure to enhance CDT but also provides hollow cavity for CAI loading. Meanwhile, the macrophage membrane-camouflaging endows the nanocatalysts with immune evading capability and improves tumoritropic accumulation by recognizing tumor endothelium and cancer cells through α4/VCAM-1 interaction. Once internalized by tumor cells, the CAI could be specifically released, which can not only inhibit CA IX to induce intracellular H+ accumulation for accelerating the Fenton reaction but also could prevent tumor metastasis because of the insufficient H+ formation outside cells for tumor extracellular matrix degradation. In addition, the HMFe can be employed to highly efficient magnetic resonance imaging to real-time monitor the agents' bio-distribution and treatment progress. Both in vitro and in vivo results well demonstrated that the nanocatalysts could realize self-amplified CDT and breast cancer metastasis inhibition via tumor microenvironment remodeling, which also provides a promising paradigm for improving CDT and antimetastatic treatment.

Multiplexed Detection of Secreted Cytokines at near-Molecular Resolution Elucidates Macrophage Polarization Heterogeneity.

Monitoring the secretion of proteins from single cells can provide important insights into how cells respond to their microenvironment. This is particularly true for immune cells, which can exhibit a large degree of response heterogeneity. Microfabricated well arrays provide a powerful and versatile method to assess the secretion of cytokines, chemokines, and growth factors from single cells, but detection sensitivity has been limited to high levels on the order of 10,000 per cell. Recently, we reported a quantum dot-based immunoassay that lowered the detection limit for the cytokine TNF-α to concentrations to nearly the single-cell level. Here, we adapted this detection method to three additional targets while maintaining high detection sensitivity. Specifically, we detected MCP-1, TGF-ß, IL-10, and TNF-α using quantum dots with different emission spectra, each of which displayed a detection threshold in the range of 1-10 fM or ∼1-2 molecules per well. We then quantified secretion of all four proteins from single macrophage cells that were stimulated toward a pro-inflammatory state with lipopolysaccharide (LPS) or toward a pro-healing state with both LPS and interleukin 4 (IL-4). We found that MCP-1 and TGF-ß were predominantly secreted at high levels only (>10,000 molecules/cell), while a substantial number of cells secreted IL-10 and TNF-α at lower levels that could only be detected using our method. Subsequent principal component and cluster analysis revealed that secretion profiles could be classified as either exclusively pro-inflammatory, including MCP-1 and/or TNF-α, or more subtle responses displaying both pro-healing and pro-inflammatory characters. Our results highlight the heterogeneous and nondiscrete nature of macrophage phenotypes following in vitro stimulation of a cell line. Future work will focus on expanding the multiplexing capacity by extending emission spectra bandwidth and/or spatially barcoding capture antibodies, as well as evaluating the enhanced detection sensitivity capabilities with normal and diseased immune cell populations in vitro and in vivo.

Polystyrene microplastics induce an immunometabolic active state in macrophages.

Anti-inflammatory and proinflammatory responses in macrophages are influenced by cellular metabolism. Macrophages are the primary phagocyte in mucosal environments (i.e., intestinal tract and lungs) acting as first-line defense against microorganisms and environmental pollutants. Given the extensive contamination of our food and water sources with microplastics, we aimed to examine the metabolic response in macrophages to microplastic particles (MPs). Utilizing murine macrophages, we assessed the metabolic response of macrophages after polystyrene MP phagocytosis. The phagocytosis of MP by macrophages induced a metabolic shift toward glycolysis and a reduction in mitochondrial respiration that was associated with an increase of cell surface markers CD80 and CD86 and cytokine gene expression associated with glycolysis. The gastrointestinal consequences of this metabolic switch in the context of an immune response remain uncertain, but the global rise of plastic pollution and MP ingestion potentially poses an unappreciated health risk. Macrophage phagocytosis of microplastics alters cellular metabolism. - Macrophages cannot degrade PS MP. - MP phagocytosis increases glycolysis in murine macrophages. - MP phagocytosis reduces mitochondrial respiration in murine macrophages.

Análise dos mecanismos pró-inflamatórios do ácido úrico solúvel: efeito sobre proteínas sensíveis à modulação redox e sobre a polarização de células THP-1 / Analysis of the pro-inflammatory mechanisms of soluble uric acid: effect on redox sensitive proteins and THP-1 cell polarization

Vários estudos epidemiológicos estabelecem correlação positiva entre os níveis de ácido úrico sérico e o aumento do risco para doenças cardiovasculares. Fatores dietéticos e socioeconômicos, além da presença de comorbidades estão diretamente associados aos níveis séricos de ácido úrico. Países desenvolvidos apresentam maior incidência e prevalência da gota e alguns grupos étnicos são particularmente susceptíveis à hiperuricemia. Cristais de ácido úrico são descritos por iniciar e perpetuar resposta inflamatória, e sinalizar um padrão de resposta molecular associado ao dano (DAMP), permitindo a diferenciação de macrófagos para perfis pró-inflamatórios. Por outro lado, os efeitos do ácido úrico em sua forma solúvel ainda carecem de estudos. Macrófagos derivados de precursores monocíticos apresentam diferenciação específica e respondem a um conjunto de fatores extrínsecos, resultando em perfis distintos, um fenômeno conhecido como polarização. Assim, os macrófagos podem ser classicamente ativados para uma resposta Th1 (T helper 1) e polarizados a um perfil pró- inflamatório (M1, resposta Th1) ou a um perfil alternativo e oposto, um perfil de resolução da inflamação (M2, resposta Th2, T helper 2). Nesse sentindo, buscamos analisar os efeitos do ácido úrico solúvel sobre vias de modulação da polarização fenotípica de macrófagos e modificação redox. Utilizamos a linhagem monocítica humana THP-1, a qual foi diferenciada em macrófagossímile por acetato miristato de forbol (PMA; 5 ng.mL-1) por 48 h, seguidas da incubação com ácido úrico em meio ausente de tióis e soro fetal bovino por 8h ou 24h (0-1000 µM). A expressão de fatores de transcrição e marcadores de polarização foi realizada através de citometria de fluxo, western-blotting e por microscopia de fluorescência com alto conteúdo de imagens (HCI). Em concentrações fisiológicas, verificamos que o ácido úrico solúvel regulou positivamente a frequência de células para receptor manose CD206, um marcador clássico de perfil alternativo/M2 e regulou negativamente a expressão óxido nítrico sintase induzível (iNOS), um marcador M1, sugerindo inicialmente uma modulação para o perfil de polarização M2. Além disso, as proteínas redoxsensíveis, heme oxigenase-1 (HO-1) e tiorredoxina (Trx) tiveram sua expressão reduzida e aumentada, respectivamente, pelo tratamento com ácido úrico. Os fatores de transcrição Nrf2 e STAT3 tiveram regulação negativa após a exposição ao ácido úrico solúvel. Os resultados apresentados nesta tese sugerem uma função do urato no priming de macrófagos através da alteração da polarização destas células

Several epidemiological studies have established a positive correlation between high serum uric acid levels and increased risk for cardiovascular diseases. Developed countries have a higher incidence and prevalence of gout and some ethnic groups are particularly susceptible to hyperuricemia. Although hyperuricemia is a prevalent condition, it has still controversy biological consequences. Uric acid crystals are described as capable of initiating and perpetuating inflammatory responses, by activating the damage-associated molecular response pattern (DAMP) cascade, allowing macrophage differentiation to inflammatory profiles. In spite of that, biological response to soluble uric acid are not completely understood. Monocyte-derived macrophages respond to a set of extrinsic factors that result in different profiles and can be polarized to a proinflammatory (M1) or anti-inflammatory (M2) profile. In this thesis, we analyzed the effects of soluble uric acid on redox-modulated pathways and the phenotypic polarization of macrophages. We used human monocytic THP-1 cell line, differentiated into macrophage by phorbol myristate acetate (PMA; 5 ng.mL-1) for 48 h. After differentiation, cells were incubated with soluble uric acid in medium without thiols and fetal bovine serum for 8 h and 24 h (0-1000 µM). The expression of transcription factors and polarization markers were assessed by flow cytometry, western-blotting and fluorescence microscopy with high content imaging (HCI). At physiological concentrations, soluble uric acid positively regulated the frequency of cells for mannose receptor CD206, a classic marker of the anti-inflammatory M2 profile and negatively regulated the inducible nitric oxide synthase (iNOS) expression, a proinflammatory M1 marker, suggesting that the soluble uric acid changes the polarization profile to M2 profile. In addition, the redox-sensitive proteins heme oxygenase-1 (HO-1) and thioredoxin (Trx) had their expression decreased and increased, respectively, after exposure to urate. STAT3 and Nrf2 transcription factors were downregulated upon soluble uric acid exposure. The results presented in this thesis suggest a role of uric acid in macrophage priming through the alteration of cell polarization

Artemisia lactiflora Extracts Prevent Inflammatory Responses of Human Macrophages Stimulated with Charcoal Pyrolysis Smoke.

Artemisia lactiflora, a Chinese-origin plant, has been reported to have unique phytochemicals responsible for its medicinal properties. The growth of the agricultural industry emits air pollution, which has adverse effects on health. There are limited scientific reports on the biological activities of A. lactiflora. Studies on its activities and mechanisms may provide insight into its use in medicinal purposes to treat those health problems and conditions. In this study, leaves of A. lactiflora were extracted and fractioned with solvents of different polarities. Total phenolics, total flavonoids DPPH• scavenging, ABTS•+ scavenging, and cytotoxicity of A. lactiflora were assessed. Anti-inflammatory activities were evaluated by pre-treating macrophages with extract or fractions then induced inflammatory response by coconut shell pyrolysis smoke. Inflammatory responses were assessed by measuring pro-inflammatory genes expression and pro-inflammatory cytokines secretion. Among all extract and fractions of A. lactiflora, butanol fraction has the highest phenolic, flavonoid, and DPPH• scavenging activity. All extract and fractions significantly down-regulated pro-inflammatory genes expression (RelA, TNF, IL6) and decreased pro-inflammatory cytokines secretion (TNF-α, IL-6), p < 0.0001, compared with pyrolysis smoke-induced macrophages. The ethyl acetate fraction showed the highest anti-inflammatory activity in decreasing pro-inflammatory cytokines secretion. These results may prove the anti-inflammatory activities of A. lactiflora through the inhibition of the NF-κB-dependent pathway. Taken together, this study first reported the anti-inflammatory activities of A. lactiflora. Thus, the plant can be used to prevent and treat inflammatory responses caused by highly oxidative pyrolysis smoke released from the re-utilization of agro-industrial leftovers.

Prognostic value of CD169-positive macrophages in various tumors: a meta-analysis.

The study aimed to evaluate the prognostic value of CD169 expression in tumor-infiltrating macrophages from regional lymph nodes (RLN) in various tumors. In order to identify eligible articles, PubMed, EMBASE, Web of Science, and Cochrane Library were used to conduct a systematic search. Pooled hazard ratios (HRs) or odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were adopted to assess the relationship between CD169 expression and overall survival (OS) and clinicopathological characteristics. Ten studies, including eleven cohorts with 1699 patients, were enrolled. We found that high CD169+ expression in tumor-infiltrating macrophages from RLN was associated with a favorable OS (HR = 0.56, 95%CI: 0.39-0.79, P = 0.001). Subgroup analysis showed that high CD169+ expression had more predictive power in digestive system tumors (HR = 0.52, 95%CI: 0.42-0.67, <0.001). In addition, high CD169 expression was significantly linked with lymph node metastasis (OR = 0.66, 95%CI: 0.47-0.94, P = 0.020) and TNM stage (OR = 0.62, 95%CI: 0.48-0.80, P < 0.001). High CD169 expression in tumor-infiltrating macrophages from RLN was correlated with favorable survival outcome in patients with malignancies. CD169 may be a novel and effective prognostic marker, especially for digestive system tumors.

Delivery of Ultrasmall Nanoparticles to the Cytosolic Compartment of Pyroptotic J774A.1 Macrophages via GSDMDNterm Membrane Pores.

Endosome capture is a major physiological barrier to the successful delivery of nanomedicine. Here, we found a strategy to deliver ultrasmall nanoparticles (<10 nm) to the cytosolic compartment of pyroptotic cells with spontaneous endosomal escape. To mimic pathological pyroptotic cells, J774A.1 macrophages were stimulated with lipopolysaccharide (LPS) plus nigericin (Nig) or adenosine triphosphate (ATP) to form specific gasdermin D protein-driven membrane pores at an N-terminal domain (GSDMDNterm). Through GSDMDNterm membrane pores, both anionic and cationic nanoparticles (NPs) with diameters less than 10 nm were accessed into the cytosolic compartment of pyroptotic cells in an energy- and receptor-independent manner, while NPs larger than the size of GSDMDNterm membrane pores failed to enter pyroptotic cells. NPs pass through GSDMDNterm membrane pores via free diffusion and then access into the cytoplasm of pyroptotic cells in a microtubule-independent manner. Interestingly, we found that LPS-primed NPs may act as Trojan horse, deliver extracellular LPS into normal cells through endocytosis, and in turn induce GSDMDNterm membrane pores, which facilitate further internalization of NPs. This study presented a straightforward method of distinguishing normal and pyroptotic cells through GSDMD membrane pores, implicating their potential application in monitoring the delivery of desired nanomedicines in pyroptosis-related diseases and conditions.

Protocol for simulating macrophage signal transduction and phenotype polarization using a large-scale mechanistic computational model.

The ability to measure and analyze the complex dynamic multi-marker features of macrophages is critical for the understanding of their diverse phenotypes and functions in health and disease. To that end, we have recently developed a multi-pathway computational model that for the first time enables a systems-level characterization of macrophage signaling and activation from quantitative, temporal, dose-dependent, and single-cell aspects. This protocol includes instructions to utilize this model to computationally explore different biological scenarios with high resolution and efficiency. For complete details on the use and execution of this protocol, please refer to Zhao et al. (2021).

Fibrillar biopolymer-based scaffolds to study macrophage-fibroblast crosstalk in wound repair.

Controlled wound healing requires a temporal and spatial coordination of cellular activities within the surrounding extracellular matrix (ECM). Disruption of cell-cell and cell-matrix communication results in defective repair, like chronic or fibrotic wounds. Activities of macrophages and fibroblasts crucially contribute to the fate of closing wounds. To investigate the influence of the ECM as an active part controlling cellular behavior, coculture models based on fibrillar 3D biopolymers such as collagen have already been successfully used. With well-defined biochemical and biophysical properties such 3D scaffolds enable in vitro studies on cellular processes including infiltration and differentiation in an in vivo like microenvironment. Further, paracrine and autocrine signaling as well as modulation of soluble mediator transport inside the ECM can be modeled using fibrillar 3D scaffolds. Herein, we review the usage of these scaffolds in in vitro coculture models allowing in-depth studies on the crosstalk between macrophages and fibroblasts during different stages of cutaneous wound healing. A more accurate mimicry of the various processes of cellular crosstalk at the different stages of wound healing will contribute to a better understanding of the impact of biochemical and biophysical environmental parameters and help to develop further strategies against diseases such as fibrosis.

Modulation of macrophage functions by ECM-inspired wound dressings - a promising therapeutic approach for chronic wounds.

Nonhealing chronic wounds are among the most common skin disorders with increasing incidence worldwide. However, their treatment is still dissatisfying, that is why novel therapeutic concepts targeting the sustained inflammatory process have emerged. Increasing understanding of chronic wound pathologies has put macrophages in the spotlight of such approaches. Herein, we review current concepts and perspectives of therapeutic macrophage control by ECM-inspired wound dressing materials. We provide an overview of the current understanding of macrophage diversity with particular view on their roles in skin and in physiological and disturbed wound healing processes. Based on this we discuss strategies for their modulation in chronic wounds and how such strategies can be tailored in ECM-inspired wound dressing. The latter utilize and mimic general principles of ECM-mediated cell control, such as binding and delivery of signaling molecules and direct signaling to cells specifically adapted for macrophage regulation in wounds. In this review, we present examples of most recent approaches and discuss ideas for their further development.