Macrophage Functional Activity Research Articles

Correlation between Complement C1q A Chain (C1QA) and Macrophages in the Progression of Carotid Atherosclerosis.

There is increasing evidence that macrophages are involved in the development of carotid atherosclerosis (CAS), but the specific mechanism is still unclear. We aimed to explore the key genes that play a regulatory role on macrophages in the progression of CAS. From 2021 August to 2023 August, GEO datasets GSE100927 and GSE43292 were downloaded and the key gene modules related to CAS were identified by weighted Gene co-expression network analysis (WGCNA). Kyoto Encyclopedia of Genes and Genes (KEGG) pathway analysis was performed on the genes of the key modules to identify common gene enrichment pathways. Differential expression analysis of pathway-related genes was performed by the "limma" package of R software. Case groups were categorized into high and low expression groups based on the expression levels of key genes, and ssGSEA immune infiltration analysis was performed. The turquoise module of GSE100924 (threshold=12) and the brown module of GSE43292 (threshold=7) were obtained through WGCNA analysis. The analysis of KEGG showed that the differentially expressed genes in the turquoise and brown modules were co-enriched in the staphylococcus aureus infection signaling pathway. Differential expression analysis identified 18 common differentially expressed genes, all of which were highly expressed in the case group. C1QA is the gene of interest. According to ssGSEA analysis, the high expression group of C1QA showed a significant increase in the number of macrophages (GSE43292, P=0.0011; GSE100927, P=0.025). This study identified the key gene C1QA involved in regulating macrophage functional activity during the CAS process, providing new ideas for effective control of CAS.

Hypoxia-inducible factor-1α promotes macrophage functional activities in protecting hypoxia-tolerant large yellow croaker (Larimichthys crocea) against Aeromonas hydrophila infection.

The immune system requires a high energy expenditure to resist pathogen invasion. Macrophages undergo metabolic reprogramming to meet these energy requirements and immunologic activity and polarize to M1-type macrophages. Understanding the metabolic pathway switching in large yellow croaker (Larimichthys crocea) macrophages in response to lipopolysaccharide (LPS) stimulation and whether this switching affects immunity is helpful in explaining the stronger immunity of hypoxia-tolerant L. crocea. In this study, transcript levels of glycolytic pathway genes (Glut1 and Pdk1), mRNA levels or enzyme activities of glycolytic enzymes [hexokinase (HK), phosphofructokinase (PFK), pyruvate kinase (PK), and lactate dehydrogenase A (LDHA)], aerobic respiratory enzymes [pyruvate dehydrogenase (PDH), isocitrate dehydrogenase (IDH), and succinate dehydrogenase (SDH)], metabolites [lactic acid (LA) and adenosine triphosphate (ATP)], levels of bactericidal products [reactive oxygen species (ROS) and nitric oxide (NO)], and transcripts and level changes of inflammatory factors [IL1β, TNFα, and interferon (IFN) γ] were detected in LPS-stimulated L. crocea head kidney macrophages. We showed that glycolysis was significantly induced, the tricarboxylic acid (TCA) cycle was inhibited, and metabolic reprogramming occurred, showing the Warburg effect when immune cells were activated. To determine the potential regulatory mechanism behind these changes, LcHIF-1α was detected and found to be significantly induced and transferred to the nucleus after LPS stimulation. LcHif-1α interference led to a significant reduction in glycolytic pathway gene transcript expression, enzyme activity, metabolites, bactericidal substances, and inflammatory factor levels; a significant increase in the aerobic respiration enzymes; and decreased migration, invasion, and phagocytosis. Further ultrastructural observation by electron microscopy showed that fewer microspheres contained phagocytes and that more cells were damaged after LcHif-1α interference. LcHif-1α overexpression L. crocea head kidney macrophages showed the opposite trend, and promoter activities of Ldha and Il1β were significantly enhanced after LcHif-1α overexpression in HEK293T cells. Our data showed that LcHIF-1α acted as a metabolic switch in L. crocea macrophages and was important in polarization. Hypoxia-tolerant L. crocea head kidney showed a stronger Warburg effect and inhibited the TCA cycle, higher metabolites, and bactericidal substance levels. These results collectively revealed that LcHif-1α may promote the functional activities of head kidney macrophages in protecting hypoxia-tolerant L. crocea from Aeromonas hydrophila infection.

EFFECT OF A COMPLEX ACTION OF OZONETHERAPY COMBINED WITH AUTOLOGOUS PLATELET-RICH PLASMA APPLICATION ON THE CHARACTER OF MORPHOFUNCTIONAL CHANGES OF THE TISSUE MACROPHAGES IN PATIENTS WITH DIABETIC FOOT SYNDROME

Summary. Objective: to study the character of ultrastructural changes in the tissue macrophages under the effect of a complex of auxiliary factors promoting reparative process activation in the wound including ozonetherapy, local application of autologous platelet-rich plasma (PRP) and vacuum therapy.
 Materials and methods. The patients examined were divided into three groups. The first group included 23 (32,85%) patients who were treated by means of regional ozone therapy. The second group included 23 (32,85%) patients treated by means of local PRP therapy. The control group included 24 (34,28%) patients who during the postoperative period received a complex of therapeutic measures according to the generally accepted method.
 Results. Stimulation of the macrophage functional activity under ozone effect with destructive changes found in the cells without necrotizing damage was found tobe explained by apoptosis mechanism involvement as a positive factor in the regulation of local homeostasis on completion of inflammatory (exudative) phase of the wound process.
 Conclusions. A complex of such auxiliary therapeutic measures confirm more determined level of the reparative process activation on the level of the tissue macrophages in both groups examined (№ 1 and №2) in comparison with the control one.
 Prospects of further research. The results obtained confirm and determine further necessity to carry out search in novations in the treatmen to diabetic foot syndrome using the factors of physical and biological effect directed to the activation of the wound reparative process.

ULTRASTRUCTURAL CHANGES OF MONONUCLEAR MACROPHAGES UNDER THE ACTION OF OZONE THERAPY AND LOCAL APPLICATION OF AUTOLOGOUS PLATELET-RICH PLASMA IN THE TREATMENT OF DIABETIC FOOT SYNDROME

Objective – to study the character of ultra- structural changes in the tissue macrophages under the eff ect to complex of accessory factors promoting reparative process activation in the wound: ozone therapy, local application of autologous platelet-rich-plasma.Materials and methods. The patients were divided into three groups. The 1st group included 23 (32,85%) individuals who were treated by means of ozone therapy. The 2nd group included 23 (32,85%) patients treated by means of local platelet-rich plasma (PRP) therapy. The control group included 24 (34,28%) individuals who received a complex of therapeutic measures according to the generally accepted method. Surgery or all the patients was performed with maximum saving of the vessels in the plantar region, and the local treatment included topical vacuum therapy in the amount of 5-6 procedures. Electronic- microscopic examination used the fragments of tissue from the wound surface preserved in 2,5% glutaraldehyde solution on phosphate buff erі (рН – 7,2-7,4), followed by further processing in 1% anhydride solution. The material was dehydrated in increasing concentration alcohols and placed into araldite. The morphological structures were contrasted with a concentrated solution of uranyl acetate in the process of dehydration, and on the sections – with lead citrate. The sections 40-60 nm thick obtained by means of ultratome УМТП-3 were examined under the electron microscope TESLA БС-500. The specimens for examination were taken in the patients during dressings on the 7, 14 and 21-23 days of treatment. The dynamics of changes in the tissue macrophages was conducted by means of Astaldi principle generalizing percentage evaluation. It is a semi-quantitative method considering distinctive cytological changes determined in the similar amount of the cells examined (tissue macrophages).Results. Stimulation of the macrophage functional activity under the eff ect of ozone with destructive changes found in the cells without necrotizing damage was found to be explained by apoptosis mechanism involved as a positive factor in the regulation of local homeostasis at the completion of infl ammatory (exudative) phase of the wound process. Activation of phagocytic possibilities of the tissue macrophages with local application of autologous platelet-rich plasma occurs without any signs of apoptosis prevailing, and it is indicative of stimulation of their functional activity by antigenic or enzymatic mechanisms stimulating their functional activity.Conclusions. Stimulation of macrophage functional activity under ozone eff ect and availability of destructive changes in the cells without necrotizing damage can be explained by the involving of apoptosis mechanism as a positive factor in the regulation of local homeostasis at the completion of infl ammatory (exudative) phase of the wound process. Activation of phagocytic possibilities of the tissue macrophages with local application of autologous platelet-rich-plasma occurs without any signs of apoptosis prevailing, and it is indicative of stimulation of their functional activity by antigenic or enzymatic mechanisms stimulating their functional activity.Prospects of further studies. The results obtained confi rm and determine further necessity to conduct search innovations in the treatment of diabetic foot syndrome using the factors of physical and biological eff ect directed to the activation of a reparative process in the wound.

Concentrated growth factor regulates the macrophage-mediated immune response.

Concentrated growth factor (CGF) is a promising regenerative material that serves as a scaffold and adjunct growth factor for tissue engineering. The host immune response, particularly macrophage activity, plays a critical role in injury repair and tissue regeneration. However, the biological effect of CGF on the immune response is not clear. To enrich the theoretical groundwork for clinical application, the present study examined the immunoregulatory role of CGF in macrophage functional activities in vitro. The CGF scaffold appeared as a dense fibrin network with multiple embedded leukocytes and platelets, and it was biocompatible with macrophages. Concentrated bioactive factors in the CGF extract enhanced THP-1 monocyte recruitment and promoted the maturation of suspended monocytes into adherent macrophages. CGF extract also promoted THP-1 macrophage polarization toward the M2 phenotype with upregulated CD163 expression, as detected by cell morphology and surface marker expression. A cytokine antibody array showed that CGF extract exerted a regulatory effect on macrophage functional activities by reducing secretion of the inflammatory factor interleukin-1β while inducing expression of the chemokine regulated on activation, normal T cell expressed and secreted. Mechanistically, the AKT signaling pathway was activated, and an AKT inhibitor partially suppressed the immunomodulatory effect of CGF. Our findings reveal that CGF induces a favorable immune response mediated by macrophages, which represents a promising strategy for functional tissue regeneration.

Computational Fine-Tuning of Functional Single Nucleotide Polymorphisms Associated with ACP5 Gene to Characterize Missense Mutations

Acid phosphatase 5 (ACP5) gene plays a vibrant role in the synthesis of a tartrate-resistant acid phosphatase (TRAP5) enzyme. TRAP5 is ~35 KD glycosylated di-iron metalloenzyme responsible for the regulation of osteopontin (protein) activity. There are two isoforms of TRAP5, TRAP5a, and TRAP5b. TRAP5a functions with low enzymatic activity due to a loop interacting with the active site and the more active TRAP5b is generated upon proteolytic cleavage of this loop. TRAP5a works as a marker for systematic macrophage function and chronic inflammation activity, while TRAP5b for osteoclast activity. ACP5 is evolutionarily conserved in nature and acts as a multifunctional protein that involves generations of reactive oxygen species, normal bone development, macrophage function, and osteoblast regulation, affecting a series of pathways, as well as reflecting bone resorption and osteoclast activity. To understand its fundamental role, a functional investigation of missense mutations of the ACP5 gene was carried out through an in-silico approach. Two nsSNPs G109R and L201P were predicted to be deleterious using multiple computational tools like SIFT, Polyphen-1, PolyPhen-2, MAPP, SNAP, Predict SNP and PhD-SNP. Additionally, the structural analysis was performed. The result is that there was no similarity between the native and mutant structures. Therefore, these reported mutations in ACP5 modify the expression, function, and structure of a TRAP5 protein. These findings suggest that TRAP5 can be a therapeutic target in immunological disorders, cancer, and metabolic bone diseases. These deleterious mutations can be lethal to its function and may hamper its therapeutic strategy leading to various diseases such as autoimmune cytopenia, systemic lupus erythematosus (SLE) immune-osseous dysplasia, spasticity with leukodystrophy, moyamoya syndrome, and sjogren's syndrome.

Impact of (Sodium) Aminophthalhydrazide on Insulin+ and Pdx1+ Rat Liver Cells in Experimental Model of Diabetes Mellitus Type I

Aim: to evaluate quantity and functional activity of insulin+ hepatic cells in response to modulation of macrophage functional activity in rats in the modelling of diabetes mellitus type 1. Materials and methods: experiment was carried out on male Wistar rats, which were divided into 3 groups: intact, DM and DM+APH. To model DM alloxan in the dose of 170 mg/kg was injected intraperitoneally, the dose of APH was 2 mg/kg intramuscularly (a total of 20 injections within 30 days). Biochemical, enzyme immunoassay, immunohistochemical and statistical research methods were used. Results: сompare to the DM, in DM+APH group the increasing numbers of insulin+ hepatocytes and insulin+ sinusoidal cells were detected. At the same time, the total number of sinusoidal cells and Pdx1+ liver cells increase in both DM and DM+APH groups. It was found, that the content of insulin in the cytoplasm of insulin+ hepatocytes significantly higher in the DM+APH group, compare to intact and diabetic animals, which indicates the impact of APH at the growth of functional activity of insulin+ hepatocytes. An increase in the expression of insulin in the hepatic cells at the modulation of macrophage activity by APH may contribute to the correction of hyperglycemia in diabetic rats. Conclusion: introduction of APH leads to an increase in the number of insulin+ hepatocytes and their insulin-producing function, as well as insulin+ sinusoidal cells in animals with experimental diabetes. An increase in the total number of sinusoidal hepatic cells when the APH was administered in animals with alloxan-induces DM was revealed. At the same time, the action of APH enhances the expression of Pdx1 — a factor of differentiation for insulin-producing cells in the liver of diabetic animals.

BRCA-1 depletion impairs pro-inflammatory polarization and activation of RAW 264.7 macrophages in a NF-κB-dependent mechanism.

BRCA-1 is a nuclear protein involved in DNA repair, transcriptional regulation, and cell cycle control. Its involvement in other cellular processes has been described. Here, we aimed to investigate the role of BRCA-1 in macrophages M(LPS), M(IL-4), and tumor cell-induced differentiation. We used siRNAs to knockdown BRCA-1 in RAW 264.7 macrophages exposed to LPS, IL-4, and C6 glioma cells conditioned medium (CMC6), and evaluated macrophage differentiation markers and functional phagocytic activity as well as DNA damage and cell survival in the presence and absence of BRCA-1. LPS and CMC6, but not by IL-4, increased DNA damage in macrophages, and this effect was more pronounced in BRCA-1-depleted cells, including M(IL-4). BRCA-1 depletion impaired expression of pro-inflammatory cytokines, TNF-α and IL-6, and reduced the phagocytic activity of macrophages in response to LPS. In CMC6-induced differentiation, BRCA-1 knockdown inhibited TNF-α and IL-6 expression which was accompanied by upregulation of the anti-inflammatory markers IL-10 and TGF-β and reduced phagocytosis. In contrast, M(IL-4) phenotype was not affected by BRCA-1 status. Molecular docking predicted that the conserved BRCA-1 domain BRCT can interact with the p65 subunit of NF-κB. Immunofluorescence assays showed that BRCA-1 and p65 co-localize in the nucleus of LPS-treated macrophages and reporter gene assay showed that depletion of BRCA-1 decreased LPS and CMC6-induced NF-κB transactivation. IL-4 had no effect upon NF-κB. Taken together, our findings suggest a role of BRCA-1 in macrophage differentiation and phagocytosis induced by LPS and tumor cells secretoma, but not IL-4, in a mechanism associated with inhibition of NF-κB.

Immunomodulatory effect of human amniotic epithelial cells on restoration of ovarian function in mice with autoimmune ovarian disease.

Autoimmune ovarian disease (AOD) is considered to be a major cause of premature ovarian failure (POF). The immunomodulatory properties of human amniotic epithelial cells (hAECs) have been studied in many disease models. We previously reported that hAECs restored ovarian function in chemotherapy-induced POF mice, but the immunomodulatory mechanism of hAECs is still unclear. To investigate the effect of hAECs on recipient mice, especially on regulatory Treg cells, hAECs and hAEC-conditioned medium (hAEC-CM) were intravenously injected into AOD mice immunized with zona pellucida protein 3 peptides (pZP3). Ovarian function was evaluated through estrous cycle, hormone secretion, follicle development, and cell apoptosis analysis. Immune cells including CD3, CD4, CD8 and Treg cells in the spleens were tested by flow cytometry. To elucidate the effect of hAEC-CM on macrophage function, inflammation model in vitro was established in RAW264.7 cells induced by lipopolysaccharide (LPS). hAECs and hAEC-CM regulated estrous cycles, promoted follicle development, ameliorated cell apoptosis and fibrosis in ovaries of AOD mice. In addition, hAECs significantly reversed the decrease of pZP3-induced Treg cells in the spleens. In vitro, hAEC-CM significantly inhibited the inflammatory reaction induced by LPS in RAW264.7 cells via up-regulating the expression of M2 macrophage genes. Further study demonstrated that hAEC-secreted transforming growth factor-beta and macrophage inhibitory factor played important roles in the macrophage polarization and migration under inflammatory stimulation. Taken together, hAECs restored ovarian function by up-regulating Treg cells in the spleens and reduced the inflammatory reaction via modulating the activated macrophage function in a paracrine manner in the ovaries of AOD mice.

Metabolic influence on macrophage polarization and pathogenesis

Macrophages play an essential role not only in mediating the first line of defense but also in maintaining tissue homeostasis. In response to extrinsic factors derived from a given tissue, macrophages activate different functional programs to produce polarized macrophage populations responsible for inducing inflammation against microbes, removing cellular debris, and tissue repair. However, accumulating evidence has revealed that macrophage polarization is pivotal in the pathophysiology of metabolic syndromes and cancer, as well as in infectious and autoimmune diseases. Recent advances in transcriptomic and metabolomic studies have highlighted the link between metabolic rewiring of macrophages and their functional plasticity. These findings imply that metabolic adaption to their surrounding microenvironment instructs activation of macrophages with functionally distinct phenotypes, which in turn probably leads to the pathogenesis of a wide spectrum of diseases. In this review, we have introduced emerging concepts in immunometabolism with focus on the impact on functional activation of macrophages. Furthermore, we have discussed the implication of macrophage plasticity on the pathogenesis of metabolic syndromes and cancer, and how the disease microenvironment manipulates macrophage metabolism with regard to the pathophysiology.

P-145 - Hyperoxia-induced macrophage dysfunction and acute lung injury are attenuated by modulation of α7nAChR via reduced HMGB1 hyperacetylation and release

Prolonged exposure to hyperoxia during mechanical ventilation (MV) can result in acute lung injury (ALI) and is associated with HMGB1 accumulation in the airways. The aim of this study was to determine whether modulation of α7 nicotinic acetylcholine receptor (α7nAChR) with either GTS-21 (partial agonist) or GAT107 (ago-PAM) could inhibit hyperoxia-induced HMGB1 accumulation in the airways and improve innate immunity and clinical outcomes. RAW 264.7 cells, treated with either GTS-21 or GAT107 in the presence of 95% O2 exhibited decreased levels of HMGB1 in culture media and enhanced phagocytic ability. Hyperacetylation of nuclear HMGB1 can lead to its release into the extracellular milieu and is observed in cells exposed to hyperoxia. Activation of α7nAChR is effective in reducing both hyperoxia-induced HMGB1 accumulation and hyperacetylation. To determine whether activation of α7nAChR-mediated macrophage function can be translated into clinical outcomes, mice were exposed to >99% O2 for 3 d with GTS-21 treatment. GTS-21 significantly decreased both the accumulation of airway levels and hyperacetylation of HMGB1, protein content and neutrophil infiltration. Therefore, α7nAChRs represent a possible pharmacological target for the treatment of HALI in patients receiving MV.

RGC32 Promotes Bleomycin-Induced Systemic Sclerosis in a Murine Disease Model by Modulating Classically Activated Macrophage Function.

Systemic sclerosis (SSc) is a multisystem autoimmune disorder that is characterized by inflammation and fibrosis in the skin and internal organs. Previous studies indicate that inflammatory cells and cytokines play essential roles in the pathogenesis of SSc; however, the mechanisms that underlie the inflammation-driven development of SSc are not fully understood. In this study, we show that response gene to complement 32 (RGC32) is abundantly expressed in mouse macrophages in the early stage of bleomycin-induced SSc. Importantly, RGC32 is required to induce the inflammatory response during the onset of SSc, because RGC32 deficiency in mice significantly ameliorates skin and lung sclerosis and inhibits the expression of inflammatory mediators inducible NO synthase (iNOS) and IL-1β in macrophages. RGC32 appears to be a novel regulator for the differentiation of classically activated macrophages (M1 macrophages). IFN-γ and LPS stimulation induces RGC32 expression in primary peritoneal macrophages and bone marrow-derived macrophages. RGC32 deficiency impairs the polarization of M1 macrophages and attenuates iNOS and IL-1β production. Mechanistically, RGC32 interacts with NF-κB proteins and promotes iNOS and IL-1β expression by binding to their promoters. Collectively, our data reveal that RGC32 promotes the onset of SSc by regulating the inflammatory response of M1 macrophages, and it may serve as a promising therapeutic target for treating SSc.

HIF1\u03b1-dependent glycolysis promotes macrophage functional activities in protecting against bacterial and fungal infection

Macrophages are important innate immune defense system cells in the fight against bacterial and fungal pathogenic infections. They exhibit significant plasticity, particularly with their ability to undergo functional differentiation. Additionally, HIF1α is critically involved in the functional differentiation of macrophages during inflammation. However, the role of macrophage HIF1α in protecting against different pathogenic infections remains unclear. In this study, we investigated and compared the roles of HIF1α in different macrophage functional effects of bacterial and fungal infections in vitro and in vivo. We found that bacterial and fungal infections produced similar effects on macrophage functional differentiation. HIF1α deficiency inhibited pro-inflammatory macrophage functional activities when cells were stimulated with LPS or curdlan in vitro or when mice were infected with L. monocytogenes or C. albicans in vivo, thus decreasing pro-inflammatory TNFα and IL-6 secretion associated with pathogenic microorganism survival. Alteration of glycolytic pathway activation was required for the functional differentiation of pro-inflammatory macrophages in protecting against bacterial and fungal infections. Thus, the HIF1α-dependent glycolytic pathway is essential for pro-inflammatory macrophage functional differentiation in protecting against bacterial and fungal infections.

Abstract 3702: Quantitative imaging of metabolic changes in macrophage subsets

Abstract Macrophages play an important role in tumor therapeutic response. However, current methods cannot image heterogeneities in macrophage activity on a single-cell level over time within intact, living samples. Macrophage metabolism is closely linked to macrophage function, as M1-like macrophages rely on aerobic glycolysis and M2-like macrophages rely on fatty acid oxidation and oxidative phosphorylation. Thus, we propose to develop optical metabolic imaging (OMI) using two-photon microscopy to monitor cell-level changes in macrophage polarization and functional activity. OMI exploits the auto-fluorescence intensities and lifetimes of the metabolic co-enzymes NAD(P)H and FAD, and has been previously used to dynamically image in vivo tumors with cell-level resolution. The optical redox ratio (fluorescence intensity of NAD(P)H divided by FAD) provides a global measure of redox balance within individual cells. The fluorescence lifetimes of NAD(P)H and FAD provide information in protein-binding activities in metabolic reactions. OMI was used to monitor metabolic changes in macrophages on a single-cell level during polarization and after metabolic perturbations. RAW 264.7 macrophages were stimulated towards an M1- or M2-like phenotype, and imaged with OMI at 24, 48, and 72 hours post-polarization. M1- and M2-like macrophages exhibited significant differences (p<0.05) in redox ratio and FAD fluorescence lifetime values at 48 and 72 hours post-polarization. The M1-like and M2-like character of the macrophages were validated with quantitative polymerase chain reaction (qPCR) analysis. Population density modeling of single-cell metabolism established differences in intra-sample heterogeneity across subsets over time. M1- and M2-like macrophages were also treated with 2-deoxy-glucose (glycolysis inhibitor), etomoxir (fatty acid oxidation inhibitor), and cyanide (oxidative phosphorylation inhibitor. Treatment with etomoxir caused a significant decrease in redox ratio in M2-like macrophages (p<0.05) with no significant effect on M1-like macrophages. In contrast, the redox ratio decreased in M1-like macrophages upon inhibition of glycolysis (p<0.05). Comparable to previously published data, inhibition of oxidative phosphorylation in both groups yielded a decreased NAD(P)H mean lifetimes (p<0.05) and increased FAD mean lifetimes (p<0.05). These results establish OMI as a method to image heterogeneity in macrophage populations within intact, living samples. This method could be used to understand macrophage interactions in the microenvironment of intact in vivo tumors. Citation Format: Tiffany M. Heaster, David L. Elion, Rebecca S. Cook, Melissa C. Skala. Quantitative imaging of metabolic changes in macrophage subsets [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3702. doi:10.1158/1538-7445.AM2017-3702

Regulation of the peritoneal macrophage functional activity by the MP-5 and MP-6 myelopeptides under stress.

In mice, two-hour immobilization stress inhibited zymosan-induced production by macrophages of the oxygen radicals and cytokine IL-1β. After myelopeptides MP-5 and MP-6 were administered into mice, the stress-induced inhibition of the reactive oxygen species (ROS) and IL-1β was abrogated. MP-5 peptide stimulated spontaneous ROS production by macrophages and reduced IL-10 production under stress. Thus, under in vivo conditions and under stress, the effect of MP-5 and MP-6 myelopeptides modulates the peritoneal macrophage activity.

Shotgun proteomic analysis of the secretome of bovine endometrial mesenchymal progenitor/stem cells challenged or not with bacterial lipopolysaccharide

The use of the conditioned medium (CM) for diseases treatment is based on its enrichment with biomolecules with therapeutic properties and themselves have a beneficial effect. Secretome of bovine endometrial mesenchymal progenitor/stem cells (eMSCs) using a proteomics approach is until now unknown. This work aimed to evaluate the secretome of bovine eMSCs-CM challenged or not with lipopolysaccharide (LPS). For this, eMSCs characterized were challenged (TG) or not (CG). The CM was collected 12h after stimulation and submitted to mass spectrometry analysis. The classification of identified proteins was done by PANTHER according to biological processes, molecular function, cellular component and protein class. 397 protein groups were identified in TG and 302 in CG. We observed positive enrichment for antibacterial response proteins, macrophage activation function, receptor-mediated endocytosis, hydrolase activity, inhibitory enzyme in TG, and for activity structural molecule and intermediate filament cytoskeleton in the CG. Our experimental model shows that eMSCs respond to LPS in the concentration used and can be used to study immune-inflammatory response, besides of the secretion of proteins mainly related to tissue remodeling, immune response and angiogenesis which is an interesting feature for use in cell therapy.

Effect of low dose irradiation on titanium particles with LPS adhered activated macrophage function and signaling pathways may be involved

Effect of low dose irradiation on titanium particles with LPS adhered activated macrophage function and signaling pathways may be involved

THE TREATMENT OF PURULENT-NECROTIC INJURIES OF PATIENTS WITH DIABETES MELLITUS USING REGIONAL PROLONGED OZONE THERAPY

In patients with ischemic-gangrenous form of diabetic foot syndrome intra-arterial injection of ozone-containing physiological solution by Seldinger’s method promotes decrease of glycemia level and produces a positive therapeutic effect on the results of a comprehensive treatment of this category of patients. Stimulation of macrophage functional activity under ozone influence as well as availability of destructive changes in the cells without necrotizing injuries can be explained by involving apoptosis mechanism as a positive factor in the regulation of local homeostasis on completion of inflammatory (exudative) phase of a traumatic process.

NBS1 is required for macrophage homeostasis and functional activity in mice

AbstractNijmegen breakage syndrome 1 (NBS1) is a component of the MRE11 complex, which is a sensor of DNA double-strand breaks and plays a crucial role in the DNA damage response. Because activated macrophages produce large amounts of reactive oxygen species (ROS) that can cause DNA lesions, we examined the role of NBS1 in macrophage functional activity. Proliferative and proinflammatory (interferon gamma [IFN-γ] and lipopolysaccharide [LPS]) stimuli led to increased NBS1 levels in macrophages. In mice expressing a hypomorphic allele of Nbs1, Nbs1∆B/∆B, macrophage activation–induced ROS caused increased levels of DNA damage that were associated with defects in proliferation, delayed differentiation, and increased senescence. Furthermore, upon stimulation, Nbs1∆B/∆B macrophages exhibited increased expression of proinflammatory cytokines. In the in vivo 2,4-dinitrofluorobenezene model of inflammation, Nbs1∆B/∆B animals showed increased weight and ear thickness. By using the sterile inflammation by zymosan injection, we found that macrophage proliferation was drastically decreased in the peritoneal cavity of Nbs1∆B/∆B mice. Our findings show that NBS1 is crucial for macrophage function during normal aging. These results have implications for understanding the immune defects observed in patients with NBS and related disorders.

A112: Vascular endothelial growth factor (VEGF) modulates functional activity of murine peritoneal macrophages in vitro

Recruitment of mononuclear phagocytes from the blood into tissues is considered to be a crucial process during inflammatory reactions, wound healing and tumor growth. Macrophages are known to reveal high plasticity and may change under the influence of microenvironment. The aim of the study was to evaluate the changes of macrophage functional activity under the influence of Vascular endothelial growth factor (VEGF) in vitro. This factor is known to be the main angiogenic factor but also possesses several immunomodulatory properties. Here we report that VEGF revealed a dose-dependent effects on cultured freshly isolated murine resident peritoneal macrophages: modulated iNOS mRNA expression, nitroxide and superoxide anion production, decreased 5′-nucleotidase (5′-N) activity, but had no influence on fluid-phase pinocytosis. Moreover, VEGF increased expression of its own mRNA via autocrine pathway as well as of VEGF protein expression. VEGF also induced up-regulation of extracellular matrix protein thrombospondin-1 (TSP-1) mRNA, which is considered as a part of macrophage activation phenotype. Production of cytokines and chemokines by macrophages was screened with the help of Multi- analyte ELISArray kits. It was found that incubation of macrophages in the presence of VEGF increased the production of angiogenic cytokines – TNF-α and IL-6 as well as several monocyte and leukocyte chemoattractants such as MCP-1, RANTES and MIP-1β. Therefore, we suggest that locally established VEGF gradient may influence inflammatory phenotype of tissue macrophages as well as potentiate their pro-angiogenic properties. This work was supported by Russian Foundation for Basic Research – Russia, Grant No. 15-04-06150 .