Interleukin-13 contributes to the occurrence of oral submucosal fibrosis

Oral submucous fibrosis (OSF) is a chronic progressive fibrosis disease that affects in oral mucosal tissues. Interleukin (IL)-13 has been implicated in the development of fibrosis in multiple organs. Indeed, it contributes to diseases such as pulmonary fibrosis, liver cirrhosis among others. Currently, its expression in OSF and the specific mechanisms are not well understood. The aim of this study was to investigate the role of IL-13 in OSF and further explore whether IL-13 regulates-polarization of M2-macrophages in OSF. Initially, in the tissues of patients with OSF, we observed a high expression of M2-macrophages and IL-13 protein. Additionally, we found a correlation between the expression of IL-13 and the stage of OSF. Arecoline inhibited the proliferation of fibroblasts (FBs) and promoted IL-13 production in vitro. Furthermore, our observations revealed that M2-macrophages increased upon co-culturing M0-macrophages with supernatants containing the IL-13 cytokine. In conclusion, our study demonstrated that arecoline stimulates FBs leading to increased secretion of IL-13, which in turn IL-13 leads to polarization of M2-macrophages and promotes the occurrence of OSF. This suggests that IL-13 may be a potential therapeutic target of OSF.

Tumor Microenvironment and Glioblastoma Cell Interplay as Promoters of Therapeutic Resistance

The invasive nature of glioblastoma is problematic in a radical surgery approach and can be responsible for tumor recurrence. In order to create new therapeutic strategies, it is imperative to have a better understanding of the mechanisms behind tumor growth and invasion. The continuous cross-talk between glioma stem cells (GSCs) and the tumor microenvironment (TME) contributes to disease progression, which renders research in this field difficult and challenging. The main aim of the review was to assess the different possible mechanisms that could explain resistance to treatment promoted by TME and GSCs in glioblastoma, including the role of M2 macrophages, micro RNAs (miRNAs), and long non-coding RNAs (lncRNAs) from exosomes from the TME. A systematic review of the literature on the role of the TME in developing and promoting radioresistance and chemoresistance of GBM was performed according to PRISMA-P (Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols) guidelines. A dedicated literature review search was also performed on the immunotherapeutic agents against the immune TME. We identified 367 papers using the reported keywords. The final qualitative analysis was conducted on 25 studies. A growing amount of evidence in the current literature supports the role of M2 macrophages and non-coding RNAs in promoting the mechanisms of chemo and radioresistance. A better insight into how GBM cells interact with TME is an essential step towards comprehending the mechanisms that give rise to resistance to standard treatment, which can help to pave the way for the development of novel therapeutic strategies for GBM patients.

Macrophages: From Simple Phagocyte to an Integrative Regulatory Cell for Inflammation and Tissue Regeneration-A Review of the Literature

The understanding of macrophages and their pathophysiological role has dramatically changed within the last decades. Macrophages represent a very interesting cell type with regard to biomaterial-based tissue engineering and regeneration. In this context, macrophages play a crucial role in the biocompatibility and degradation of implanted biomaterials. Furthermore, a better understanding of the functionality of macrophages opens perspectives for potential guidance and modulation to turn inflammation into regeneration. Such knowledge may help to improve not only the biocompatibility of scaffold materials but also the integration, maturation, and preservation of scaffold-cell constructs or induce regeneration. Nowadays, macrophages are classified into two subpopulations, the classically activated macrophages (M1 macrophages) with pro-inflammatory properties and the alternatively activated macrophages (M2 macrophages) with anti-inflammatory properties. The present narrative review gives an overview of the different functions of macrophages and summarizes the recent state of knowledge regarding different types of macrophages and their functions, with special emphasis on tissue engineering and tissue regeneration.

[Mechanisms of the wound-healing action of native collagen type I in ischemic model full-thickness skin wounds on the example - medical devices Collost «(part I)]

Active collagen type I successfully used in regenerative medicine. However, despite the large amount of material of cellular and molecular mechanisms underlying skin repair, the molecular mechanisms of wound healing with use collagen type I, not studied enough.

PURPOSE OF THE STUDY

To study the mechanism of the native collagen type I wound-healing action of native type I collagen on the example of the medical device Collost (7% gel) in a model of the rats difficult-to-heal skin wounds.

MATERIAL AND METHODS

Male rats in population SD (72 individuals) surgically formed an ischemic dorsal skin flap (3×10 cm) with two full-thickness skin wounds 6 mm in diameter.The trained animals divided into 2 groups: in the experimental group, medical device Collost (gel) applied once after the operation, in the control group - a standard medical device for comparison. The dynamics of wound healing assessed, the number of M2 macrophages, myofibroblasts, vascularization and expression of the main markers of the repair process in the wound tissues and time points for assessment were: after 3, 7 and 14 days after operation using macroscopic, immunohistochemical, and molecular methods.

RESULTS

It has been established that the mechanism of action of native collagen type I is associated with the acceleration of the appearance of «progenitorous» M2-macrophages in the wound tissues, decrease in the severity of inflammation or reduction in the duration of the inflammatory stage of the repair process, change in the expression spectrum of number of growth factors, an acceleration of neovasculogenesis.

CONCLUSION

In this work, on the modern experimental model shown regenerative efficiency of a medical device based on collagen type I and described the molecular and cellular processes of wound healing when using it It has been shown that the acceleration of wound healing processes occurs when using a medical device based on native collagen type 1, it is also accompanied by a better aesthetic closure of the damaged skin area.

TIE2-expressing monocytes and M2-polarized macrophages impact survival and correlate with angiogenesis in adenocarcinoma of the pancreas

Introduction

M2-polarized tumor-associated macrophages (TAMs) and TIE2-expressing monocytes (TEMs) are associated with angiogenesis and have been identified as a potential prognostic marker in several solid tumors, including hepatobiliary malignancies. However, little is known regarding their influence on tumor progression and patient survival in pancreatic ductal adenocarcinoma (PDAC).

Results

Patients with tumors characterized by the presence of CD163⁺ TAMs or TEMs in TCA or TIF, respectively, showed a significantly decreased 1-, 3- and 5-year overall and recurrence-free survival compared to patients without CD163⁺ TAMs or TEMs (all ρ < 0.05). Patients with TEMs in TCA showed a higher incidence of tumor recurrence (ρ < 0.05). Furthermore, the presence of CD163⁺ TAMs was associated with a higher tumor MVD (ρ < 0.05).

Conclusions

Presence of M2-polarized TAMs and TEMs is associated with a decreased overall and recurrence-free survival of patients with PDAC.

Materials and methods

The localization and density of CD163⁺ M2-polarized TAMs and TEMs were quantified in the tumor central area (TCA) and tumor-infiltrating front (TIF) in human PDAC tissue (n = 106) and correlated to clinicopathological characteristics, tumor recurrence rates and patient survival. In parallel, tumor microvascular density (MVD) and the density of angiopoietin-positive tumor cells were quantified. Statistical analysis was performed using SPSS software.

High density of M2-macrophages in acral lentiginous melanoma compared to superficial spreading melanoma

AIMS

Acral lentiginous melanoma (ALM) is the most common type of melanoma in people with darker skin phototypes. There is some evidence that the aetiology, pathogenesis, risk factors and natural history of ALM differ from those of superficial spreading melanoma (SSM). ALM behaves more aggressively than SSM, but the biological explanation for these differences remains unknown. The presence of one subtype of macrophages, termed M2-macrophage (M2-M), has been found to be related to local progression, metastasis and poor prognosis in several neoplasms. The aim of this study was to compare the density of M2-Ms in ALMs versus SSMs, and to examine whether or not the density of M2-Ms is associated with histopathological features predictive of adverse prognosis in cutaneous melanoma (CM), as well as development of metastasis.

METHODS AND RESULTS

Sixty-seven ALMs and 67 SSMs cases were analysed. The tumours were classified according to thickness, ulceration, mitosis and metastasis. M2-M quantity was evaluated using immunohistochemistry with anti-CD163 and anti-CD206 antibodies. M2-Ms were increased in ALM compared with SSM, and were related to the histopathological features predictive of adverse prognosis in CM, such as thickness > 1.0 mm, ulceration and mitotic activity, and the development of metastasis.

CONCLUSIONS

Our study is the first, to our knowledge, to demonstrate the increased presence of M2-Ms in ALM compared with SSM. Our findings suggest that the increased M2-Ms in ALM are associated with the main histopathological features predictive of adverse prognosis in CM, as well as the presence of metastasis, and that these cells can be related to the aggressive behaviour seen in ALMs.

Human mesenchymal stromal cell-secreted lactate induces M2-macrophage differentiation by metabolic reprogramming

Human mesenchymal stromal cells (MSC) have been shown to dampen immune response and promote tissue repair, but the underlying mechanisms are still under investigation. Herein, we demonstrate that umbilical cord-derived MSC (UC-MSC) alter the phenotype and function of monocyte-derived dendritic cells (DC) through lactate-mediated metabolic reprogramming. UC-MSC can secrete large quantities of lactate and, when present during monocyte-to-DC differentiation, induce instead the acquisition of M2-macrophage features in terms of morphology, surface markers, migratory properties and antigen presentation capacity. Microarray expression profiling indicates that UC-MSC modify the expression of metabolic-related genes and induce a M2-macrophage expression signature. Importantly, monocyte-derived DC obtained in presence of UC-MSC, polarize naïve allogeneic CD4⁺ T-cells into Th2 cells. Treatment of UC-MSC with an inhibitor of lactate dehydrogenase strongly decreases lactate concentration in culture supernatant and abrogates the effect on monocyte-to-DC differentiation. Metabolic analysis further revealed that UC-MSC decrease oxidative phosphorylation in differentiating monocytes while strongly increasing the spare respiratory capacity proportional to the amount of secreted lactate. Because both MSC and monocytes are recruited in vivo at the site of tissue damage and inflammation, we propose the local increase of lactate concentration induced by UC-MSC and the consequent enrichment in M2-macrophage generation as a mechanism to achieve immunomodulation.

A unique anti-CD115 monoclonal antibody which inhibits osteolysis and skews human monocyte differentiation from M2-polarized macrophages toward dendritic cells

Cancer progression has been associated with the presence of tumor-associated M2-macrophages (M2-TAMs) able to inhibit anti-tumor immune responses. It is also often associated with metastasis-induced bone destruction mediated by osteoclasts. Both cell types are controlled by the CD115 (CSF-1R)/colony-stimulating factor-1 (CSF-1, M-CSF) pathway, making CD115 a promising target for cancer therapy. Anti-human CD115 monoclonal antibodies (mAbs) that inhibit the receptor function have been generated in a number of laboratories. These mAbs compete with CSF-1 binding to CD115, dramatically affecting monocyte survival and preventing osteoclast and macrophage differentiation, but they also block CD115/CSF-1 internalization and degradation, which could lead to potent rebound CSF-1 effects in patients after mAb treatment has ended. We thus generated and selected a non-ligand competitive anti-CD115 mAb that exerts only partial inhibitory effects on CD115 signaling without blocking the internalization or the degradation of the CD115/CSF-1 complex. This mAb, H27K15, affects monocyte survival only minimally, but downregulates osteoclast differentiation and activity. Importantly, it inhibits monocyte differentiation to CD163⁺CD64⁺ M2-polarized suppressor macrophages, skewing their differentiation toward CD14^-CD1a⁺ dendritic cells (DCs). In line with this observation, H27K15 also drastically inhibits monocyte chemotactic protein-1 secretion and reduces interleukin-6 production; these two molecules are known to be involved in M2-macrophage recruitment. Thus, the non-depleting mAb H27K15 is a promising anti-tumor candidate, able to inhibit osteoclast differentiation, likely decreasing metastasis-induced osteolysis, and able to prevent M2 polarization of TAMs while inducing DCs, hence contributing to the creation of more efficient anti-tumor immune responses.

Cancer-associated fibroblasts and macrophages: Friendly conspirators for malignancy

Inflammation, which is now recognized as an hallmark of cancer, is intimately linked to the reactivity of stromal fibroblasts. Accumulating evidence indicate that cancer-associated fibroblasts not only drive the epithelial-mesenchymal transition and metabolically sustain the growth of cancer cells, but also engage in a reciprocal relationship with M2 macrophages that dramatically boost malignancy.