M2-type Macrophages Research Articles

Toll-like receptor 2-mediated ERK activation significantly upregulates interleukin-6 expression in M2-polarized macrophages

Abstract Objectives M2-polarized macrophages and interleukin (IL)-6 significantly alter the tumor microenvironment and promote the malignant behaviors of tumor cells. This study aimed to establish M2-type macrophages from THP-1 cells, which are human leukemia monocytes, and investigate the significance of toll-like receptor 2 (TLR2) signaling in IL-6 production. Methods THP-1 cells were treated with phorbol 12-myristate 13-acetate, IL-4, and IL-13 to stimulate their differentiation into M2 macrophages. Cell differentiation was confirmed by cytokine production, marker expression, and morphological alterations. Treatment with TLR agonists induced TLR stimulation in M2 macrophages. Subsequently, secretion and expression levels of IL-6 in M2 macrophages were measured using enzyme-linked immunosorbent assay, quantitative reverse transcription-polymerase chain reaction, and western blotting. Results Myeloid differentiation factor 88, tumor necrosis factor-associated factor 6, and IL-1 receptor-associated kinase-1/4 signaling pathways contributed to IL-6 production upon TLR2 activation in M2 macrophages. While both TLR2 and TLR4 activated NF-κB in M2 macrophages, IL-6 production was mainly dependent on TLR2, not TLR4, suggesting the involvement of major mechanisms other than NF-κB in IL-6 production. Notably, TLR2-stimulated extracellular signal-regulated kinase (ERK) was necessary for abundant IL-6 production, indicating that TLR2-mediated ERK signaling plays an essential role in M2 macrophages. Conclusions These results highlight the significance of TLR2 signaling in IL-6 production by M2 macrophages and provide insights into the underlying regulatory mechanisms.

Shen-Bai-Jie-Du decoction suppresses the progression of colorectal adenoma to carcinoma through regulating gut microbiota and short-chain fatty acids

BackgroundShen-Bai-Jie-Du decoction (SBJDD), a traditional Chinese herb formula developed based on evidence-based medicine, is efficacy to reduce the recurrence and carcinogenesis of colorectal adenoma. However, the mechanism of SBJDD to treat colorectal adenoma remains unclear. The present study aims to investigate the efficacy and mechanism of SBJDD on colorectal adenoma carcinogenesis from the aspects of regulating gut microbiota and short-chain fatty acids (SCFAs).MethodsTwenty-one patients diagnosed with colorectal adenoma were recruited in the study and required to take SBJDD for four consecutive weeks. Analysis of gut microbiota was conducted using 16S rRNA gene amplicon sequencing, while levels of SCFAs in fecal and serum samples were determined through HPLC–MS/MS. Additionally, twenty-four Apcmin/+ mice were randomly assigned to normal diet (ND), high-fat diet (HFD), and SBJDD groups. The pharmacological effects and mechanism of SBJDD on colorectal adenoma carcinogenesis were assessed using RT-qPCR, HE staining, IHC staining, Western blot, IF staining, and Flow cytometry assays.ResultsOur clinical study has shown that SBJDD can regulate the gut microbiota composition and enhance SCFAs production in patients with colorectal adenoma. SBJDD alleviated colorectal adenoma formation and carcinogenesis, as well as protected the integrity of the intestinal barrier in the Apcmin/+ mice model compared to the HFD group. Additionally, SBJDD was found to regulate gut microbiota capable of producing SCFAs. G protein-coupled receptors GPR43, GPR41, and GPR109a were effectively activated in the SBJDD group, while HDAC1 and HDAC3 were inhibited. Furthermore, decreased expression levels of interleukin 1 beta (IL-1β) and interleukin 6 (IL-6), along with elevated expression level of interleukin 10 (IL-10), were observed in the colorectal tissue of the SBJDD group. Finally, SBJDD exhibited the ability to reduce the proportion of M1-type macrophages while increasing the proportion of M2-type macrophages.ConclusionsOur study objectively demonstrated the pharmacological effects of SBJDD in inhibiting the progression of colorectal adenoma and investigated its mechanisms in terms of regulating gut microbiota, increasing SCFAs, and reducing colorectal inflammation.

Collaboration in Contradiction: Self-Adaptive Synergistic ROS Generation and Scavenge Balancing Strategies Used for the Infected Wounds Treatment.

The rational utilization of ROS is key to treating infected wounds. Exogenous ROS can destroy bacterial structures, quickly kill bacteria, and inhibit secondary infections. However, excess ROS at the wound will cause a secondary inflammatory response. Acute infections exacerbate this damage by increasing endogenous ROS, complicating the maintenance of ROS homeostasis. Therefore, regulating the balance of ROS production and scavenging in wounds has emerged as a promising strategy for wound treatment. Conventional ROS balancing platforms are mostly based on the " all for one" strategy of functional superposition and lack self-adaptability and integration. To subvert this conventional strategy, this study proposes a "one for all" self-adaptive integrated photodynamic therapy (PDT)-antioxidant model to actively regulate the ROS balance. A gelatin-hyaluronic acid hydrogel embedded with Se-modified cerium dioxide nanoparticles (Gel-HA-Se@CeO2 NPs) is designed for treating infected wounds. The Se@CeO2 NPs serve both as nanoenzymes and photosensitizers(PS). As nanoenzymes, they exhibit catalase and superoxide dismutase activities, converting hydrogen peroxide and superoxide anions into oxygen. As a PS, it synergizes with oxygen under NIR irradiation to rapidly produce singlet oxygen. Additionally, Se modification enhances the PDT effects by disrupting bacterial antioxidant systems. In vitro and in vivo experiments revealed that the ROS balance platform polarizes M1-type macrophages to M2-type macrophages, altering the wound microenvironment from proinflammatory to prohealing. RNA sequencing revealed that this hydrogel accelerated the reconstruction of the vascular network of the wound by activating the PI3K/AKT pathway and increasing VEGF secretion.This strategy is believed to be beneficial not only for infected wounds but also for treating other conditions that involve the regulation of reactive oxygen species, such as tumors and bacterial infections.

Time-Dependent Electrical Active and Ultrasound-Responsive Calcium Titanate Implant Coating with Immunomodulation, Osteogenesis, and Customized Antibacterial Activity.

Surgical site infection and insufficient osseointegration are notable risks factors associated with oral implant surgery. In this study, the development of a polarized calcium titanate (CT-P) coating for titanium surfaces is proposed as a solution to these problems. The coating generated electrical stimulation (ES) can inhibit pro-inflammatory M1-type macrophage polarization and promote anti-inflammatory M2-type macrophage polarization, resulting in favorable bone immunomodulation. The ES generated by the coating can match the physiological electrical potential that will change during bone repair, thereby promoting osseointegration in vivo. In addition, the system can also achieve on-demand antibacterial activity, mainly depending on the CT-P coating responding to ultrasound (US) irradiation to produce reactive oxygen species (ROS) and remove Staphylococcus aureus (S. aureus) on the surface of the implant. In conclusion, this work provides valuable insights for the development and clinical application of highly efficient electroactive coatings, as well as novel solutions for the selective treatment of bacterial infections in the surgical area.

Soluble CD146 cooperates with VEGF-A to generate an immunosuppressive microenvironment in CD146-positive tumors: interest of a combined antibody-based therapy.

Tumor development necessitates immune escape through different mechanisms. To counteract these effects, the development of therapies targeting Immune Checkpoints (ICP) has generated interest as they have produced lasting objective responses in patients with advanced metastatic tumors. However, many tumors do not respond to inhibitors of ICP, necessitating to further study the underlying mechanisms of exhaustion. Vascular Endothelial Growth Factor a (VEGFa), a pro-angiogenic molecule secreted by tumors, was described to participate to tumor immune exhaustion by increasing ICP, justifying in part the use of an anti-VEGFa monoclonal antibody (mAb), bevacizumab, in patients. However, recent studies from our group have demonstrated that tumors can escape anti-VEGFa therapy through the secretion of soluble CD146 (sCD146). In this study, we show that both VEGFa and sCD146 cooperate to create an immunosuppressive microenvironment by increasing the expression of ICP. In addition, sCD146 favors pro-tumoral M2-type macrophages and induces the secretion of pro-inflammatory cytokines. An anti-sCD146 mAb reverses these effects and displays additive effects with anti-VEGFa antibody to eliminate tumors in a syngeneic murine model grafted with melanoma cells. Combining bevacizumab with mucizumab could thus be of major therapeutic interest to prevent immune escape in malignant melanoma and other CD146-positive tumors.

Dectin-1 participates in the immune-inflammatory response to mouse Aspergillus fumigatus keratitis by modulating macrophage polarization

AimThe aim of this study was to investigate whether Dectin-1 influences the immune-inflammatory response in A. fumigatus keratitis by modulating macrophage polarization.Methods1. The models of 1-day, 3-day, and 5-day of fungal keratitis were established in SPF C57BL/6 mice after stimulation by A. fumigatus. Dectin-1 agonist (curdlan) and antagonist (laminaran) were injected separately in the mouse subconjunctivae for 1 day in the established mouse model of A. fumigatus keratitis; PBS was used as the control. Inflammation of the mouse cornea was observed under a slit lamp to obtain a clinical score. 2. The expression of M1 (TNF-α, INOS, IL-6, IL-12) and M2 (Arg-1, IL-10, Fizz-1, Ym-1) cytokine-encoding mRNAs was quantified by RT-PCR. 3. Changes in the number of macrophages and expression of M1 and M2 macrophages in mouse corneas detected by immunofluorescence and flow cytometry. 4. Pre-treatment of RAW264.7 cells with MAPK cell signaling pathway inhibitors SB203580 (p38 inhibitor, 10µM), U0126 (ERK inhibitor, 20µM), SP600125 (JNK inhibitor, 10µM) and DMSO separately for 2 h, and stimulated by A. fumigatus for 12 h. Changes in the mRNA expression of M1 and M2 cytokines in the macrophages were quantified by RT-PCR.Results1. With curdlan pre-treatment, mouse corneal inflammation worsened, and the clinical score increased after infection. In contrast, in the laminaran pre-treated group, corneal inflammation was alleviated and the clinical score decreased significantly compared to the PBS group after infection. 2. Compared with the control group, the expression levels of macrophage phenotype-related M1 and M2 cytokine mRNAs increased significantly 1, 3, and 5 days after A. fumigatus infected the corneas of mice. 3. With curdlan pre-treatment, the expression of mRNAs encoding M1 cytokines increased, while those encoding M2 cytokines decreased in the cornea compared to the PBS group. In contrast, after infection, mRNA levels for M1 cytokines decreased significantly and those for M2 cytokines increased in the cornea of the laminaran pre-treated group compared to the PBS group. 4. The number of macrophages in the corneal stroma of mice in the curdlan pretreatment group increased significantly compared with the PBS group, while in the laminaran pretreatment group this number decreased significantly. 5. The results of flow cytometry showed that after 3 days of mouse corneal A. fumigatus infection, the number of macrophages in the mouse A. fumigatus model in the curdlan pretreatment group was increased (10.4%) and the number of macrophages in the mouse A. fumigatus model in the laminaran pretreatment group (6.31%), when compared with the AF+FBS group (7.91%). The proportion of M1-type macrophages was increased in the curdlan pretreated group (55.6%) compared to the AF+FBS group (51.2%), the proportion of laminaran pretreatment group had a decreased proportion of M1-type macrophages (46.8%); while M2-type macrophages were the opposite of M1-type: the proportion of M2-type macrophages was 49.2% in the AF+FBS group, the proportion of M2-type macrophages was decreased in the curdlan pretreatment group (44.0%), and the proportion of M2-type macrophages was increased in the laminaran pretreatment group (53.5%). 6. Expression of M1 and M2 cytokine-encoding mRNAs decreased and increased, respectively, after infection, in the RAW264.7 cells pre-treated with MAPK pathway inhibitors, compared to the control.ConclusionIn a mouse model of A. fumigatus keratitis, Dectin-1 can affect macrophage recruitment and polarization, may regulate macrophage phenotype-associated factor changes through the MAPK signaling pathway.

Mechanisms of HIF1A-mediated immune evasion in gastric cancer and the impact on therapy resistance

BackgroundThe high prevalence and detrimental effects on patient outcomes make gastric cancer (GC) a significant health issue that persists internationally. Existing treatment modalities exhibit limited efficacy, prompting the exploration of immune checkpoint inhibitors as a novel therapeutic approach. However, resistance to immunotherapy poses a significant challenge in GC management, necessitating a profound grasp of the intrinsic molecular pathways.MethodsThis study focuses on investigating the immunosuppressive mechanisms of quiescent cancer cells (QCCs) in GC, particularly their resistance to T-cell-mediated immune responses. Utilizing mouse models, gene editing techniques, and transcriptome sequencing, we aim to elucidate the interactions between QCCs, immune cells, and key regulatory factors like HIF1A. Functional enrichment analysis will further underscore the role of glycolysis-related genes in mediating immunosuppression by QCCs.ResultsThe cancer cells that survived GC treated with T-cell therapy lost their proliferative ability. QCCs, as the main resistance force to immunotherapy, exhibit stronger resistance to CD8+ T-cell attack and possess higher cancer-initiating potential. Single-cell sequencing analysis revealed that the microenvironment in the QCCs region harbors more M2-type tumor-associated macrophages and fewer T cells. This microenvironment in the QCCs region leads to the downregulation of T-cell immune activation and alters macrophage metabolic function. Transcriptome sequencing of QCCs identified upregulated genes related to chemo-resistance, hypoxia, and glycolysis. In vitro cell experiments illustrated that HIF1A promotes the transcription of glycolysis-related genes, and silencing HIF1A in QCCs enhances T-cell proliferation and activation in co-culture systems, induces apoptosis in QCCs, and increases QCCs' sensitivity to immune checkpoint inhibitors. In vivo, animal experiments showed that silencing HIF1A in QCCs can inhibit GC growth and metastasis.ConclusionUnraveling the molecular mechanisms by which QCCs resist T-cell-mediated immune responses through immunosuppression holds promising implications for refining treatment strategies and enhancing patient outcomes in GC. By delineating these intricate interactions, this study contributes crucial insights into precision medicine and improved therapeutic outcomes in GC management.

Prenylated Dihydroflavonol from Sophora flavescens Regulate the Polarization and Phagocytosis of Macrophages In Vitro

As an important member of innate immunity, macrophages show remarkable plasticity and heterogeneity, and play an important role in immune regulation, tissue development, homeostasis of the internal environment and injury repair. However, the excessive activation of macrophages is closely related to the occurrence and development of many diseases. The prenylated flavonoid structure is one of the characteristic structures isolated from Sophora flavescens, with anti-inflammatory, anti-tumor, anti-allergy and other effects. In this study, the effects of (2R)-3β,7,4′-trihydroxy-5-methoxy-8-prenylflavanone (TMP), a prenylated dihydroflavonol, on the polarization and phagocytosis of macrophages were systematically studied. In LPS-induced M1-type macrophages, TMP dose-dependently inhibited the expression of COX-2, iNOS and the secretion of NO, IL-1β, IL-6 and IL-18, showing an inhibitory effect on M1 polarization. Further experiments revealed that it was related to the inhibition of TLR4-related AKT/mTOR, MAPK and NF-κB signaling pathways; in IL-4-induced M2-type macrophages, TMP down-regulated the expression of M2-related Arg1, IL-10, TGF-β, CD206 and CD163, as well as the phosphorylation levels of AKT1 and STAT6. For macrophages in a physiological state, it was very important for cells to return from a stress state to a phenotypic stability in the M0 state. These results indicated that TMP negatively regulated the M1/M2 polarization of macrophages, and made them tend to M0 homeostasis, which might provide new theoretical and data support for explaining the anti-inflammatory immunoregulatory activity of Sophora flavescens.

Intelligent Hydrogel with Physiologically Dependent Capacities of Photothermal Conversion and Nanocatalytic Medicine to Integratively Inhibit Bacteria and Inflammation for On-Demand Treatment of Infected Wound.

Although chemodynamic therapy (CDT) and photothermal therapy (PTT) based on a variety of nanoparticles have been developed to achieve effective anti-bacterial therapy, the limited therapeutic efficiency of CDT alone, as well as the undifferentiated damage of PTT to both bacteria and surrounding healthy tissue are still challenges for their clinical application of infected wounds treatments. In addition, during the CDT and PTT-mediated antimicrobial processes, the endogenous macrophages would be easily converted to pro-inflammatory macrophages (M1 phenotype) under local ROS and hyperthermia to promote inflammation, resulting in unexpected suppression of tissue regeneration and possible wound deterioration. To address these problems, a biodegradable sodium alginate/hyaluronic acid hydrogel loaded with functional CeO2-Au nano-alloy (AO@ACP) is fabricated to not only achieve precise and efficient antibacterial activity through infection-environment dependent photothermal-chemodynamic therapy but also rapidly eliminate the excess reactive oxygens (ROS) in the M1 type macrophage at the infected area to induce their polarization to M2 type for significant inhibition of inflammation and remarkable enhancement of tissue regeneration, hopefully developing an effective strategy to treat infected wound.

Bacterial outer membrane vesicles-clothed nanoparticles delivered by live macrophages for potentiating antitumor photoimmunotherapy

Tumor-associated macrophage (TAM) plays an important role in tumor immune regulation. Reprogramming TAMs to reshape immunosuppressive tumor microenvironment (TME) is a promising antitumor strategy. Herein, imiquimod (R837) and black phosphorus quantum dots (BPQDs) are encapsulated in bacterial outer membrane vesicles (OMVs)-clothed liposomes to obtain RB@OL nanoparticles, which are further delivered by M1-type macrophages through phagocytic loading (RB-OL@M). Owing to the natural homing ability of macrophages to tumor sites, RB-OL@M actively targets cancerous region after intravenous injection. Meanwhile, upon laser irradiation, RB@OL is released from macrophages to exert combinational photoimmunotherapy due to the excellent phototherapeutic property of BPQDs and TAM regulating potential of R837. Benefiting from this versatile strategy, RB-OL@M effectively delays the growth of 4 T1 breast tumors and prevents the occurrence of their dreadful lung metastasis, largely prolonging the survival of 4 T1 tumor-bearing mice. Overall, this work offers a promising antitumor approach based on live cell-mediated multirole nanoplatform.

Single-cell analysis reveals that TCF7L2 facilitates the progression of ccRCC via tumor-associated macrophages

BackgroundTumor-associated macrophages (TAMs) play an important role in the recurrence and progression of clear cell renal cell carcinoma (ccRCC). However, the specified mechanism has not been elucidated. MethodsSingle-cell and transcriptome analysis were applied to characterize the heterogeneity of TAMs. SCENIC would infer regulators of different subsets of TAMs. The CellChat algorithm was used to infer macrophage-tumor interaction networks, whereas pseudo-time traces were used to parse cell evolution and dynamics. ResultsIn this study, single-cell transcriptomic data of ccRCC were analyzed. Notably, the macrophages were clustered to select the cluster with a tendency toward M2-type TAM, which has an impact on the occurrence and metastasis of ccRCC. This macrophage cluster was defined as “TAM2”. And this study revealed that TCF7L2 as a potential transcription factor regulating TAM2 transcriptional heterogeneity and differentiation. Pseudotime traces showed TCF7L2 trajectories during TAM2 cell cluster development. In addition, the results of cell interaction showed that TAM2 had the highest number and strength of interactions with cancer cells and endothelial cells. In vitro experiments, this study found that TCF7L2 was highly expressed in TAMs and promoted the polarization of macrophages to M2-type macrophages. And then overexpression of TCF7L2 in macrophages markedly promoted ccRCC invasion and proliferation. ConclusionTCF7L2 could play a key role in the progression of ccRCC via enhancing TAMs recruitment and M2-type polarization.

Quercetin Promotes the M1-to-M2 Macrophage Phenotypic Switch During Liver Fibrosis Treatment by Modulating the JAK2/STAT3 Signaling Pathway.

To investigate the underlying mechanism by which quercetin (Que) regulates macrophage polarization and its subsequent therapeutic effect on liver fibrosis, an important pathological precondition for hepatocellular carcinoma (HCC). In vitro experiments were performed on the RAW264.7 mouse macrophage line. After the induction of M1-type macrophages with LPS, the effects of Que on cell morphology, M1/M2 surface marker expression, cytokine expression, and JAK2/STAT3 expression were analyzed. In vivo, male SD rats were used as a model of CCL4-induced hepatic fibrosis, and the effects of Que on serum aminotransferase levels, the histopathological structure of liver tissues, and macrophage-associated protein expression in liver tissues were analyzed. In vitro experiments revealed that Que can suppress the activation of the JAK2/STAT3 signaling pathway, leading to decreases in the expression of M1 macrophage surface markers and cytokines. Additionally, Que was found to increase the expression of M2 macrophage surface markers and cytokines. In vivo, assays demonstrated that Que significantly ameliorated the development of inflammation and fibrosis in a rat liver fibrosis model. Que can inhibit hepatic fibrosis by promoting M1 to M2 macrophage polarization, which could be associated with its ability to suppress the JAK2/STAT3 signaling pathway in macrophages.

Oncogenic miRNAs dependent photothermal-immunotherapy enhanced by on-demand manipulation of immunosuppressive microenvironment using engineered gold nanoparticles for effective treatment of primary and metastatic tumor

Although photothermal-immunotherapy has emerged as a promising strategy to treat malignant tumor, unexpected thermal damage, continuous tumor migration and immunosuppressive microenvironment still limit its application. To improve the therapeutic efficacy, two types of engineered gold nanoparticles (SNAs@CCM and SNA2@CCM-Man) were fabricated. The SNAs@CCM are cancer cell membrane (CCM, tumor targeting agent) coated spherical nucleic acids (SNAs, miR-21 catcher and photothermal agent). The SNAs contained two types (SNA1 and SNA2), which are gold nanoparticles grafted with the first half and second half of anti-miR-21 oligonucleotide, respectively. The SNA2@CCM-Man are CCM coated SNA2 (miR-21 catcher) in which the CCM was functionalized by mannose (Man, macrophage targeting agent). These nanoparticles were expected to not only perform miR-21 dependent photothermal-immunotherapy in tumor cells to precisely damage primary tumor and activate the anti-tumor immune response against metastatic tumor, but also restrain the miR-21 expression in tumor-associated M2-type macrophages to promote their polarization to tumor-suppressed M1-type macrophages for on-demand manipulation of immunosuppressive microenvironment avoiding immune escape. After injection, the SNAs@CCM and SNA2@CCM-Man would respectively internalize by tumor cells and M2-type macrophages via homologous targeting of cancer cell membranes and receptor-ligand interactions of mannose. Upon entry into tumor cells, the SNAs specifically hybridized with the over-expressed miR-21 in these cells, thereby silencing the oncogenic miR-21 and leading to significant intracellular aggregation of SNAs. These aggregated SNAs not only served as miR-21 catcher, but performed a strong absorption in the near-infrared region acting as in situ photothermal agents. Under NIR irradiation, these photothermal agents enable highly selective photothermal-immunotherapy, inducing the immunogenic death of primary tumors and subsequent anti-tumor immune responses via the maturation of dendritic cells (DCs) and activation of T cells. Moreover, the miR-21 plunder process also effectively inhibited the migration of tumor cells to further enhance the therapeutic efficacy. Simultaneously, the similar miR-21 capture process mediated by SNA2 in M2 macrophages continuously induced macrophage polarization towards the anti-tumor M1 type, which was able to reverse the immunosuppressive microenvironment in tumor tissue to avoid immune escape and enhance immunotherapy. Both in vivo and in vitro experiments demonstrated that our nanoparticles could inhibit the primary tumor and its metastasis through miR-21-dependent photothermal immune activation and directional polarization of macrophages, providing a promising strategy for on-demand synchronous modulation of tumor cells and immune cells in tumor tissues for better malignant tumor therapy.

Corticosteroids Augment Cyclosporine Nephrotoxicity in Pediatric Nephrotic Syndrome: Potential Role of CD163+ M2-type Macrophage

Corticosteroids Augment Cyclosporine Nephrotoxicity in Pediatric Nephrotic Syndrome: Potential Role of CD163+ M2-type Macrophage

Curcumin Alleviates Airway Inflammation in Cough-Variant Asthmatic Rats by Modulating M1/M2 Macrophage Polarization.

With the increase of environmental pollution and atypical pathogen infections, the incidence of cough variant asthma (CVA) has been increasing annually, making it a pressing issue of the medical community. This study aims to observe the ameliorative effect of curcumin on a rat model of cough variant asthma. A rat model of cough variant asthma was induced by sensitization with ovalbumin combined with aluminum hydroxide (Al(OH)3), followed by repeated excitations. The drug was administered on the day of the initial nebulized attack, and gavage was administered for 14 d. Pathological changes in the lung tissues were observed, along with the assessment of cough susceptibility and airway resistance. The number of inflammatory cell eosinophils and leukocytes were determined in alveolar lavage fluid. Additionally, serum inflammatory factors and lung tissues Matrix Metalloproteinase-9 (MMP-9) protein were assessed. The level of M1/M2 macrophages was also detected. Following the administration of curcumin, there was reduced inflammatory infiltration, less disordered arrangement of the lung tissue, and decreased abnormal proliferation of lung tissues in cough variant asthma rats compared to the model group. Curcumin treatment led toa notable reduction in cough frequency, a significant decrease in pro-inflammatory factor concentration levels in serum and inflammatory cell counts in the alveolar lavage fluid, and a marked increase in anti-inflammatory factor levels (p < 0.05). Additionally, curcumin administration led to a significant increase in M2-type macrophage levels, while simultaneously decreasing the levels of M1-type macrophages (p < 0.05). The administration of curcumin effectively ameliorates ovalbumin-induced airway inflammation in cough-variant asthma rats. This effect is attributed to modulating macrophage polarization towards the anti-inflammatory M2 phenotype, thereby reducing airway inflammation, airway hyperresponsiveness, and lung tissue injury.

SPI1+CD68+ macrophages as a biomarker for gastric cancer metastasis: a rationale for combined antiangiogenic and immunotherapy strategies

BackgroundTumor-associated macrophages (TAMs) have been demonstrated to be associated with tumor progression. However, the different subpopulations of TAMs and their roles in gastric cancer (GC) remain poorly understood. This study...

Mesenchymal stem cells alleviate autoimmune thyroiditis by modulating macrophage phenotypes and through influencing the STING pathway

BackgroundHashimoto's thyroiditis is a chronic autoimmune inflammatory disease with a high prevalence and currently lacks effective treatment options. Previous preclinical and clinical trials have established mesenchymal stem cells (MSCs) as a promising therapeutic approach; however, there is limited research on MSC treatment for Hashimoto's thyroiditis, and the underlying molecular mechanisms remain unclear. MethodsMSCs isolated from 4 to 6-week-old Lewis rats were employed for thyroiditis treatment. The efficacy of MSCs was assessed through histological and serological parameters. Molecular mechanisms of MSC therapy for Hashimoto's thyroiditis were explored by examining macrophage presence within thyroid tissue and relevant pathways. ResultsIn this study, we observed elevated oxidative stress and endoplasmic reticulum stress within the thyroid tissue of Hashimoto's thyroiditis patients, and MSC therapy effectively mitigated this process. Furthermore, we found that the therapeutic potential of MSCs in the EAT model depended on the STING pathway. MSCs reduced endoplasmic reticulum stress and inflammasome levels within the thyroid tissue by modulating the STING pathway. Additionally, MSCs inhibited the expression of IRE1α in thyroid tissue macrophages, thereby reducing the polarization of M1-type macrophages ConclusionsThe STING pathway appears to be a crucial mechanism by which MSCs modulate macrophage polarization in thyroid tissue, offering a potential treatment for thyroiditis.

Mechanistic studies of tumor-associated macrophage immunotherapy.

Tumor-associated macrophages (TAMs) are present in the tumor microenvironment and can polarize into subtypes with different functions and characteristics in response to different stimuli, classifying them into anti-tumorigenic M1-type and pro-tumorigenic M2-type. The M1-type macrophages inhibit tumor growth through the release of pro-inflammatory cytokines, whereas the M2-type macrophages contribute to tumor progression through the promotion of tumor proliferation, angiogenesis and metastasis. Due to the duality of macrophage effects on tumors, TAMs have been a hot topic in tumor research. In this paper, the heterogeneity and plasticity of TAMs, the interactions between TAMs and other immune cells, and the effects of TAMs on tumors are reviewed, and the therapeutic strategies for TAMs are summarized and discussed. These therapeutic strategies encompass methods and approaches to inhibit the recruitment of TAMs, deplete TAMs, and modulate the polarization of TAMs. These studies help to deeply understand the mechanism of TAMs-tumor interaction and provide reference for combination therapy of tumors.

Identification of Gαi3 as a promising molecular oncotarget of pancreatic cancer.

The increasing mortality rate of pancreatic cancer globally necessitates the urgent identification for novel therapeutic targets. This study investigated the expression, functions, and mechanistic insight of G protein inhibitory subunit 3 (Gαi3) in pancreatic cancer. Bioinformatics analyses reveal that Gαi3 is overexpressed in human pancreatic cancer, correlating with poor prognosis, higher tumor grade, and advanced classification. Elevated Gαi3 levels are also confirmed in human pancreatic cancer tissues and primary/immortalized cancer cells. Gαi3 shRNA or knockout (KO) significantly reduced cell viability, proliferation, cell cycle progression, and mobility in primary/immortalized pancreatic cancer cells. Conversely, Gαi3 overexpression enhanced pancreatic cancer cell growth. RNA-sequencing and bioinformatics analyses of Gαi3-depleted cells indicated Gαi3's role in modulating the Akt-mTOR and PKA-Hippo-YAP pathways. Akt-S6 phosphorylation was decreased in Gαi3-depleted cells, but was increased with Gαi3 overexpression. Additionally, Gαi3 depletion elevated PKA activity and activated the Hippo pathway kinase LATS1/2, leading to YAP/TAZ inactivation, while Gαi3 overexpression exerted the opposite effects. There is an increased binding between Gαi3 promoter and the transcription factor TCF7L2 in pancreatic cancer tissues and cells. Gαi3 expression was significantly decreased following TCF7L2 silencing, but increased with TCF7L2 overexpression. In vivo, intratumoral injection of Gαi3 shRNA-expressing adeno-associated virus significantly inhibited subcutaneous pancreatic cancer xenografts growth in nude mice. A significant growth reduction was also observed in xenografts from Gαi3 knockout pancreatic cancer cells. Akt-mTOR inactivation and increased PKA activity coupled with YAP/TAZ inactivation were also detected in xenograft tumors upon Gαi3 depletion. Furthermore, bioinformatic analysis and multiplex immunohistochemistry (mIHC) staining on pancreatic cancer tissue microarrays showed a reduced proportion of M1-type macrophages and an increase in PD-L1 positive cells in Gαi3-high pancreatic cancer tissues. Collectively, these findings highlight Gαi3's critical role in promoting pancreatic cancer cell growth, potentially through the modulation of the Akt-mTOR and PKA-Hippo-YAP pathways and its influence on the immune landscape.

Insect Cuticle Protein Nanoassemblies without Nonspecific Immune Response for Acute Methicillin-Resistant Staphylococcus aureus Pneumonia Remission.

The emergence and proliferation of methicillin-resistant Staphylococcus aureus (MRSA) pneumonia poses a significant global public health threat. Herein, the significant remission effect against acute MRSA pneumonia was realized through the insect cuticle protein (OfCPH-2) nanoassemblies without nonspecific immune response. The lung repair results could be attributed to the transforming of M1-type to M2-type macrophage polarization and the repression of Th17 cell differentiation in mice spleens through the intervention of OfCPH-2 nanoassemblies. These findings offer a valuable insight into the application of insect protein-based materials as effective antidrug resistant strain agents as well as a powerful strategy for acute MRSA pneumonia.