CD163-positive M2 Macrophages Research Articles

Subconjunctival administration of mesenchymal stem cells alleviates ocular inflammation in a murine model of corneal alkali burn.

Corneal alkali burns cause extensive damage not only on the cornea but also into the intraocular tissues. As an anti-inflammatory therapy, subconjunctival administration of mesenchymal stem cells (MSCs) for corneal protection after corneal alkali burn has been explored. Little evidence demonstrates the potential of subconjunctival MSCs delivery in protecting the post-burn intraocular tissues. This study aimed to evaluate the therapeutic efficacy of subconjunctival injection of human placental (hP)-MSCs in protecting against ocular destruction after the burn. hP-MSCs were subconjunctivally administered to C57/BL mice after corneal alkali burn. Western blot of iNOS and CD206 was performed to determine the M1, M2 macrophage infiltration in the cornea. Infiltration of inflammatory cells in the anterior uvea and retina were analyzed by flow cytometry. The TUNEL assay or Western blot of Bax and Bcl2 was used to evaluate the anti-apoptotic effects of MSCs. MSCs could effectively facilitate cornea repair by suppressing inflammatory cytokines IL-1β, MCP-1, and MMP9, and polarizing CD206 positive M2 macrophages. Anterior uveal and retinal inflammatory cytokines expression and inflammatory cells infiltration were inhibited in the MSC-treated group. Reduced TUNEL positive staining and Bax/Bcl2 ratio indicated the anti-apoptosis of MSCs. MSC-conditioned medium promoted human corneal epithelial cell proliferation and regulated LPS-stimulated inflammation in RAW 264.7 macrophages, confirming the trophic and immunoregulatory effects of MSCs. Our findings demonstrate that subconjunctival administration of MSCs exerted anti-inflammatory and anti-apoptotic effects in the cornea, anterior uvea, and retina after corneal alkali burn. This strategy may provide a new direction for preventing post-event complications after corneal alkali burn.

Prognostic implications of histologic growth patterns and tumor-infiltrating macrophages in colorectal liver metastases.

Histopathologic patterns at the invasion fronts of tumors predict metastatic potential and prognosis in several cancers. We examined whether such patterns at the interface between colorectal liver metastases and hepatic parenchyma have similar prognostic value. Microscopic growth patterns at edges of metastases including desmoplasia, pushing borders, and replacement of hepatocytes were retrospectively analyzed with respect to surgical outcomes in 142 patients who underwent hepatectomy for colorectal metastases. Patterns included desmoplasia in 58 patients (41%), hepatocyte replacement in 41 (29%), and pushing borders in 43 (30%). Maximum metastasis diameter and serum carcinoembryonic antigen concentration in patients showing desmoplastic tumor growth were lower than those in others (P < 0.05 and P < 0.01). Disease-free survival and overall survival were better in patients showing desmoplastic growth, while a non-desmoplastic tumor growth pattern showed a negative influence. More cluster of differentiation (CD) 68-positive M1 macrophages and fewer CD206-positive M2 macrophages were demonstrated at interfaces of tumors with hepatic parenchyma when desmoplasia was present, although markers for proliferative activity (MIB1 index) and metastatic potential (E-cadherin expression) appeared uninfluenced by desmoplasia. Better long-term results were associated with metastatic tumors showing desmoplastic growth patterns at invasion fronts, which may reflect local immune state in a prognostically useful manner.

A study on the correlation between M2 macrophages and regulatory T cells in the progression of colorectal cancer.

M2 macrophages and regulatory T cells (Tregs) can promote tumors and development by inhibiting the anti-tumor immune response. This study investigated the effect of CD163-positive M2 macrophages and Foxp3-positive Tregs in the progression of colorectal cancer and lymph node metastasis. It also investigated the correlation between M2 macrophages and Tregs. Postoperative tissue specimens and clinical data were collected from 197 patients with colorectal cancer who underwent initial surgical treatment in The Second Ward of Colorectal Surgery of the First Affiliated Hospital of Jinzhou Medical University from March 2020 to December 2020. Immunohistochemical methods were used to detect the expression levels of CD163 protein-labeled M2 macrophages and Foxp3 protein-labeled Tregs in colorectal cancer tissues, matched paracancer tissues, and lymph node tissues. The correlation between CD163 and Foxp3 in cancer tissues and lymph node tissues were analyzed, as well as the relationship between clinicopathological characteristics and preoperative tumor markers. M2 macrophages and Tregs were importantly positively correlated in cancer and lymph node tissues, which significantly increased in cancer and metastatic lymph node tissues. Interestingly, M2 macrophages in non-metastatic lymph nodes also increased significantly in patients with metastatic lymph nodes. In addition, both CD163 and Foxp3 were upregulated with increasing tumor node metastasis stage, depth of infiltration, and lymphatic metastasis; and both were positively correlated with carcinoembryonic antigen. CD163 may be a good predictor of pre-metastatic status of colorectal cancer lymph nodes. carcinoembryonic antigen affects the distribution of M2 macrophages and Tregs in colorectal cancer. There is a certain correlation between the two types of cells. It is possible that M2 macrophages, together with suppressor Tregs cells, promote an immunosuppressive environment.

Delayed Supplementation Strategy of Extracellular Vesicles from Adipose-Derived Mesenchymal Stromal Cells with Improved Proregenerative Efficiency in a Fat Transplantation Model.

Background Mesenchymal stromal cells (MSCs) and their secreted extracellular vesicles (MSC-EVs) possess similar proregenerative effects when injected into defects immediately following trauma. However, MSC-EVs are superior to MSCs in terms of storage and rejection reflection, while immediate administration of MSC-EVs is related to several target cells for most donor cells die within few weeks. Besides, the inflammatory cascade is incited, providing an unfavorable environment for target cells. We hypothesized that delayed injection of MSC-EVs might have priority on tissue regeneration than instant injection. Method Extracellular vesicles isolated from adipose-derived mesenchymal stromal cells (ADSC-EVs) were administered into human umbilical vein endothelial cells (HUVECs) in vitro at different doses. The migration of HUVECs was assessed using the scratch wound healing assay, whereas the length of tubes and number of vessel-like structures formed by HUVECs were determined using tube formation assay. Next, 24 BALB/c nude mice were randomly divided into three groups (n = 8). For the EV-delayed group, ADSC-EVs were injected into transplanted fat a week later than the EV-immediate group. The volume and weight of grafts were measured at 3 months after fat transplantation. Further, the number of CD31-possitive vessels and CD206-possitive cells in the fat grafts was quantified. Results Compared with the EV-immediate group, the EV-delayed group had a higher fat tissue retention volume (0.11 ± 0.02 mL versus 0.08 ± 0.01 mL), more neovessels (31.00 ± 4.60 versus 24.20 ± 3.97), and fewer cysts. Furthermore, there were more Ki67-positive cells (25.40 ± 7.14 versus 16.20 ± 4.17) and CD206-positive M2 macrophages cells (23.60 ± 3.44 versus 14.00 ± 3.85) in the EV-delayed group than in the EV-immediate group. Conclusion Delayed injection of ADSC-EVs promotes fat graft volume retention by stimulating angiogenesis. These findings suggest that delayed supplementation might be a more effective strategy for the application of MSC-EVs in tissue regeneration.

A case of patch granuloma annulare with CD68‐negative, CD163‐positive M2 macrophages infiltration in an interstitial pattern

Patch granuloma annulare is a rare type of granuloma annulare. Histopathologically, patch granuloma annulare shows interstitial infiltration of histiocytes. In our case, immunohistochemical analyses demonstrated CD68-negative, CD163-positive M2 macrophages infiltration in an interstitial pattern. Patch granuloma annulare (GA), a rare type of GA, is marked by asymptomatic and nonspecific skin discoloration that progresses slowly.1 Histopathologically, patch GA shows an interstitial pattern, whereas classic GA usually shows a palisading pattern, and both patterns are different in immunohistochemical findings.2 Here, we report a case of patch granuloma annulare with CD68-negative, CD163-positive M2 macrophages infiltration in an interstitial pattern. A 52-year-old Japanese woman presented with subtle, irritated erythematous-to-brown macules and patches that increased in size and number on the legs over one year. Physical examination showed well-demarcated and smooth macules, coalescing into large patches, which were distributed symmetrically and geographically on her extremities (Figure 1A,B). She had no chronic disease or medication use, and her laboratory tests were normal. Since topical corticosteroids and oral anti-allergic drugs had been ineffective, a skin biopsy was taken from her thigh. The histopathological result showed numerous histiocytes that infiltrated between interstitial collagen in the upper and middle dermis with some mucin deposition, which were particularly dense around vessels (Figure 1C–F). The characteristic skin lesions and pathological findings led to the diagnosis of patch granuloma annulare. The NB-UVB treatment was performed based on previous reports3 and almost all lesions faded away after 31 sessions of the exposure (total cumulative dose 19.4 J/cm2). In our case, histopathological and immunohistochemical analyses demonstrated an interstitial pattern of GA with negative CD68 and positive CD163 staining (Figure 1G). GA can be divided into two main types according to histopathology: palisading and interstitial patterns. The former shows focal palisaded granulomatous inflammation, and the latter shows interstitial infiltration of histiocytes. Classic GA often shows a palisading pattern, but it sometimes shows an interstitial pattern; in this situation, it is difficult to reach a diagnosis because of the inconsistency between histopathological findings and the characteristic skin rash. The finding that CD68 and CD163 staining corresponds with histiocytes of the palisading granuloma in the palisading pattern of GA is useful. In the interstitial pattern, CD163 staining corresponds with the histiocytes of the stroma, but CD68 staining is absent.2 CD68 is a pan-macrophage marker and CD163 is an M2 macrophage marker.4 It has been reported that the M1/M2 macrophage ratio reflects inflammatory activity based on the observation that M1 macrophages are pro-inflammatory and M2 macrophages are anti-inflammatory.5 These histopathological and immunohistochemical analyses may lead to the correct diagnosis and evaluation of clinical disease activity of GA. Patch GA is often asymptomatic or just mildly irritating and itchy, and the skin rash is inconspicuous and slowly enlarges. It often disappears spontaneously or in response to topical steroids, but it can also expand over a prolonged period, as was seen in the present case.6-8 The reason for such a mild condition may be related to the large proportion of CD163-positive anti-inflammatory M2 macrophages. In conclusion, patch GA is a rare form of GA characterized by a mild skin rash with an indolent course. Histopathological and immunohistochemical evaluation of the ratio of M1/M2 macrophages may contribute to understanding the disease activity. The authors declare no conflicts of interest. Approval of the research protocol: N/A. Informed consent: N/A. Registry and the Registration No. of the study/trial: N/A. Animal studies: N/A.

In Vitro Model of Human Skeletal Muscle Tissue for the Study of Resident Macrophages and Stem Cells.

Simple SummaryThe skeletal muscle of younger adults has a remarkable regenerative capacity, which substantially declines with age. Despite many interspecies differences, animals have been used to study new treatments to promote muscle regeneration in humans. This study reports a novel human experimental model using human skeletal muscle tissue of older adults that was extracted during surgical procedures. We describe an optimal procedure for maintaining human skeletal muscle tissue under experimental conditions for 11 days. This experimental model allows the investigation of resident macrophages and stem cells, which mediate muscle regeneration.Findings from studies of muscle regeneration can significantly contribute to the treatment of age-related loss of skeletal muscle mass, which may predispose older adults to severe morbidities. We established a human experimental model using excised skeletal muscle tissues from reconstructive surgeries in eight older adults. Muscle samples from each participant were preserved immediately or maintained in agarose medium for the following 5, 9, or 11 days. Immunofluorescence analyses of the structural proteins, actin and desmin, confirmed the integrity of muscle fibers over 11 days of maintenance. Similarly, the numbers of CD80-positive M1 and CD163-positive M2 macrophages were stable over 11 days in vitro. However, the numbers of PAX7-positive satellite cells and MYOD-positive myoblasts changed in opposite ways, suggesting that satellite cells partially differentiated in vitro. Further experiments revealed that stimulation with unsaturated fatty acid C18[2]c (linoleic acid) increased resident M1 macrophages and satellite cells specifically. Thus, the use of human skeletal muscle tissue in vitro provides a direct experimental approach to study the regulation of muscle tissue regeneration by macrophages and stem cells and their responses to therapeutic compounds.

Role of Macrophages and Mast Cells as Key Players in the Maintenance of Gastrointestinal Smooth Muscle Homeostasis and Disease.

The gut contains the largest macrophage pool in the body, with populations of macrophages residing in the mucosa and muscularis propria of the gastrointestinal (GI) tract. Muscularis macrophages (MMs), which are located within the muscularis propria, interact with cells essential for GI function, such as interstitial cells of Cajal, enteric neurons, smooth muscle cells, enteric glia, and fibroblast-like cells, suggesting that these immune cells contribute to several aspects of GI function. This review focuses on the latest insights on the factors contributing to MM heterogeneity and the functional interaction of MMs with other cell types essential for GI function. This review integrates the latest findings on macrophages in other organs with increasing knowledge of MMs to better understand their role in a healthy and diseased gut. We describe the factors that contribute to (muscularis macrophage) MM heterogeneity, and the nature of MM interactions with cells regulating GI function. Finally, we also describe the increasing evidence suggesting a critical role of another immune cell type, the mast cell, in normal and diseased GI physiology.

Fc fragment of immunoglobulin G receptor IIa (FCGR2A) as a new potential prognostic biomarker of esophageal squamous cell carcinoma.

Fc fragment of immunoglobulin G receptor IIa (FCGR2A) as a new potential prognostic biomarker of esophageal squamous cell carcinoma.

P-420 Pre-selected for an award: Uncomplicated oocyte donation pregnancies display elevated CD163 positive type 2 macrophage load in the decidua, which is associated with fetal-maternal HLA class II mismatches

Abstract Study question Do quantity and composition of decidual macrophages differ between uncomplicated oocyte donation (OD) pregnancies and non-OD in vitro fertilization (IVF) pregnancies? Summary answer OD placentas show higher decidual CD163 positive fraction within the total macrophage population compared to non-OD IVF placentas. What is known already The embryo of an OD pregnancy is completely allogeneic to the mother, which may lead to a bigger challenge for the maternal immune system to tolerize the fetus compared to autologous pregnancies. Placental macrophages may be essential in maintaining a healthy pregnancy. Macrophages can be classified into different categories based on phenotype and characteristics, in which type 2 macrophages are thought to exhibit immune suppressive activity. Study design, size, duration This retrospective case-control study included patients who delivered in the Leiden University Medical Center between January 1st 2006 and July 1st 2016. A total of 42 pregnancies were enrolled in this study, conceived by uncomplicated singleton OD pregnancies (n = 25) or non-OD IVF pregnancies (n = 17). Medical records were reviewed and clinical data were collected. Placental tissue samples were collected for immunohistochemical staining and blood samples were collected for HLA typing. Participants/materials, setting, methods Placentas were collected and immunohistochemically stained for CD14 (pan-macrophage marker) and CD163 (type 2 macrophage marker). The extent of staining was quantitated by digital image analysis software. To assess mismatching, maternal and fetal DNA was typed for HLA-A, -B, C, -DRB1, and -DQB1. Main results and the role of chance A significantly lower percentage of CD14 positive staining was observed in the decidua basalis of OD pregnancies compared to non-OD IVF pregnancies (p = 0.030). Consequently, the CD163/CD14 ratio in OD group was higher than in non-OD IVF group (p = 0.243). In the parietalis, OD pregnancies demonstrated a significantly higher percentage of CD163+ staining (p = 0.040) and a significantly higher CD163/CD14 ratio (p = 0.032) compared to non-OD IVF group. The reproducibility of this quantitative analysis was found to be high. OD group was separated into a syngeneic group (number of mismatches lower than half of the antigens per HLA locus) and an allogeneic group (number of mismatches higher than half of the antigens per HLA locus). Significant differences of CD163+ and CD163/CD14 ratio were found in the decidua parietalis when comparing the HLA-classII-allogeneic OD group with the non-OD IVF group (p = 0.047). This difference was not found for the HLA-class-II-syngeneic OD group. Limitations, reasons for caution Our study only focused on decidua basalis and parietalis, no other locations in the placentas. Larger sample size might be needed to verify the association between macrophages and HLA mismatches. Wider implications of the findings To our knowledge, this study is the first to quantify a higher CD163 positive M2 macrophages load within the total decidual macrophages of uncomplicated OD pregnancy compared to non-OD IVF pregnancies. Trial registration number not applicable

P–420 uncomplicated oocyte donation pregnancies display elevated CD163 positive type 2 macrophage load in the decidua, which is associated with fetal-maternal HLA class II mismatches

Abstract Study question Do quantity and composition of decidual macrophages differ between uncomplicated oocyte donation (OD) pregnancies and non-OD in vitro fertilization (IVF) pregnancies? Summary answer OD placentas show higher decidual CD163 positive fraction within the total macrophage population compared to non-OD IVF placentas. What is known already The embryo of an OD pregnancy is completely allogeneic to the mother, which may lead to a bigger challenge for the maternal immune system to tolerize the fetus compared to autologous pregnancies. Placental macrophages may be essential in maintaining a healthy pregnancy. Macrophages can be classified into different categories based on phenotype and characteristics, in which type 2 macrophages are thought to exhibit immune suppressive activity. Study design, size, duration This retrospective case-control study included patients who delivered in the Leiden University Medical Center between January 1st 2006 and July 1st 2016. A total of 42 pregnancies were enrolled in this study, conceived by uncomplicated singleton OD pregnancies (n = 25) or non-OD IVF pregnancies (n = 17). Medical records were reviewed and clinical data were collected. Placental tissue samples were collected for immunohistochemical staining and blood samples were collected for HLA typing. Participants/materials, setting, methods Placentas were collected and immunohistochemically stained for CD14 (pan-macrophage marker) and CD163 (type 2 macrophage marker). The extent of staining was quantitated by digital image analysis software. To assess mismatching, maternal and fetal DNA was typed for HLA-A, -B, C, -DRB1, and -DQB1. Main results and the role of chance A significantly lower percentage of CD14 positive staining was observed in the decidua basalis of OD pregnancies compared to non-OD IVF pregnancies (p = 0.030). Consequently, the CD163/CD14 ratio in OD group was higher than in non-OD IVF group (p = 0.243). In the parietalis, OD pregnancies demonstrated a significantly higher percentage of CD163+ staining (p = 0.040) and a significantly higher CD163/CD14 ratio (p = 0.032) compared to non-OD IVF group. The reproducibility of this quantitative analysis was found to be high. OD group was separated into a syngeneic group (number of mismatches lower than half of the antigens per HLA locus) and an allogeneic group (number of mismatches higher than half of the antigens per HLA locus). Significant differences of CD163+ and CD163/CD14 ratio were found in the decidua parietalis when comparing the HLA-classII-allogeneic OD group with the non-OD IVF group (p = 0.047). This difference was not found for the HLA-class-II-syngeneic OD group. Limitations, reasons for caution Our study only focused on decidua basalis and parietalis, no other locations in the placentas. Larger sample size might be needed to verify the association between macrophages and HLA mismatches. Wider implications of the findings: To our knowledge, this study is the first to quantify a higher CD163 positive M2 macrophages load within the total decidual macrophages of uncomplicated OD pregnancy compared to non-OD IVF pregnancies. Trial registration number Not applicable

Generation and Evaluation of Novel Biomaterials Based on Decellularized Sturgeon Cartilage for Use in Tissue Engineering.

Because cartilage has limited regenerative capability, a fully efficient advanced therapy medicinal product is needed to treat severe cartilage damage. We evaluated a novel biomaterial obtained by decellularizing sturgeon chondral endoskeleton tissue for use in cartilage tissue engineering. In silico analysis suggested high homology between human and sturgeon collagen proteins, and ultra-performance liquid chromatography confirmed that both types of cartilage consisted mainly of the same amino acids. Decellularized sturgeon cartilage was recellularized with human chondrocytes and four types of human mesenchymal stem cells (MSC) and their suitability for generating a cartilage substitute was assessed ex vivo and in vivo. The results supported the biocompatibility of the novel scaffold, as well as its ability to sustain cell adhesion, proliferation and differentiation. In vivo assays showed that the MSC cells in grafted cartilage disks were biosynthetically active and able to remodel the extracellular matrix of cartilage substitutes, with the production of type II collagen and other relevant components, especially when adipose tissue MSC were used. In addition, these cartilage substitutes triggered a pro-regenerative reaction mediated by CD206-positive M2 macrophages. These preliminary results warrant further research to characterize in greater detail the potential clinical translation of these novel cartilage substitutes.

Overexpression of PLXDC2 in Stromal Cell-Associated M2 Macrophages Is Related to EMT and the Progression of Gastric Cancer.

The tumor microenvironment (TME) comprises distinct cell types, including stromal types such as fibroblast cells and macrophage cells, which have recently become a critical factor in tumor development and progression. Here, we identified the TME-related gene, plexin domain containing 2 (PLXDC2), in a high-stromal-score population. And we revealed that this gene was related to poor survival and advanced (tumor-node-metastasis) stage in gastric cancer (GC) patients from The Cancer Genome Atlas database. An integrated gene profile and functional analysis of the proportions of tumor-infiltrating immune cells revealed that the expression of the M2 macrophages cell marker CD163 was positively correlated with PLXDC2 expression. In addition, the M2 macrophages gene signature and high PLXDC2 expression were associated with the inflammatory signaling pathway and the epithelial-to-mesenchymal transition (EMT)-related gene signature. Single-cell study of GC identified PLXDC2 was enriched specifically in fibroblasts and monocytes/macrophages populations, which supported its important role in the stroma. Furthermore, according to a tissue microarray immunohistochemistry analysis, the expression of PLXDC2 elevated in human GC stromal specimens compared to tumor tissue specimens. Moreover, PLXDC2 overexpression in the stromal compartment was associated with CD163-positive regulatory M2 macrophages, and its functions were related to the pathogenesis of GC. Multiplexed immunohistochemistry verified PLXDC2’s correlation with EMT markers. Our data suggested that PLXDC2 was expressed in stromal cells and that its crosstalk with tumor-associated macrophages could contribute to cancer biology by inducing the EMT process.

M2 tumor-associated macrophages play important role in predicting response to neoadjuvant chemotherapy in triple-negative breast carcinoma.

Two types of macrophages are present in tumor microenvironment. M1 macrophages exhibit potent anti-tumor properties, while M2 macrophages play the pro-tumoral roles. The presence of M2 macrophages is associated with worsened overall survival in triple-negative breast carcinoma (TNBC) patients. However, the relationship between M2 macrophages and response to neoadjuvant chemotherapy (NAC) is unknown. M2 macrophages were investigated on biopsy whole sections from 66 TNBCs treated with NAC by CD163 together with other immune checkpoint markers (PD1, PD-L1 and CD8) using a multi-color immunohistochemical multiplex assay. Incomplete response was significantly associated with older age, lower PD-L1 expression (tumor and stroma), lower levels of CD8-positive TILs in stroma, but higher level of CD163-positive macrophages, with the level of CD163-positive M2 macrophages in peritumoral area as the strongest factor. Our data have demonstrated that the level of CD163-positive M2 macrophages was significantly higher in TNBC patients with incomplete response than patients with complete response, suggesting M2 macrophages' important role in predicting TNBC patients' response to NAC.

PLOD2-driven IL-6/STAT3 signaling promotes the invasion and metastasis of oral squamous cell carcinoma via activation of integrin β1.

We previously reported that high expression of procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (PLOD2) leads to stabilization and plasma membrane translocation of integrin β1 to promote the invasion and metastasis of oral squamous cell carcinoma (SCC). The present study aimed to further understand the relationship between PLOD2-integrin β1 signaling and the tumor microenvironment. This study provided further advanced insights indicating that elevated interleukin (IL)-6 in the tumor microenvironment acts as a key molecule that triggers PLOD2-integrin β1 axis-derived acceleration of tumor invasion and metastasis. It was found using the dual-luciferase reporter assay system that signal transducer and activator of transcription 3 (STAT3) activation by IL-6 was essential for increasing the expression levels of PLOD2 through direct activation of the PLOD2 promoter in oral SCC, whereas IL-6 stimulation did not contribute to integrin β1 expression or the subsequent maturation process towards a functional form on the plasma membrane. Furthermore, the expression of IL-6 in oral SCC tissues was mainly observed in the tumor stroma. Finally, with double immunofluorescence staining, it was found that IL-6 expression occurred in CD163-positive M2 macrophages distributed around the tumor nest. These results combined with our previous results indicate that as IL-6 significantly increases STAT3-mediated PLOD2 promoter activity, IL-6 released by M2-type tumor-associated macrophages is a crucial factor that promotes PLOD2-integrin β1 axis-enhanced invasion and metastasis of oral SCC cells.

A study of the correlation between M2 macrophages and lymph node metastasis of colorectal carcinoma

BackgroundLymph node metastasis is a major prognostic sign of colorectal carcinoma and an important indicator for individualized treatment. M2 macrophages play a key role in carcinogenesis and tumor development by enhancing invasiveness and promoting lymph node metastasis. The purpose of this study was to investigate the effect of CD163-positive M2 macrophages on lymph node metastasis in colorectal carcinoma.MethodsPostoperative lymph node tissues were obtained from 120 patients with colorectal carcinoma who underwent radical surgery in the First Affiliated Hospital of Jinzhou Medical University between December 2019 and May 2020. We detected the expression of the CD163 protein in lymph nodes using immunohistochemistry. Furthermore, the relationships between M2 macrophages identified by expression of CD163 and lymph node metastasis were analyzed using the independent sample t-test and Chi-square test.ResultsM2 macrophages were increased in metastatic lymph nodes and non-metastatic lymph nodes adjacent to the cancer. The M2 macrophage count was higher in patients with macro-metastases than in patients with micro-metastases.ConclusionsThe presence of M2 macrophages represents an important indicator for lymph node metastasis in colorectal carcinoma and may be a potential marker for its prediction. Thus, M2 macrophage localization might offer a new target for the comprehensive treatment of colorectal carcinoma.

Immunomodulatory effect of dimethyloxallyl glycine/nanosilicates-loaded fibrous structure on periodontal bone remodeling

Background/purposeRelieving immuno-inflammatory responses is the prerequisite step for treating periodontitis. The angiogenic small molecule, dimethyloxalylglycine (DMOG), and osteoinductive inorganic nanomaterial, nanosilicate (nSi) have a powerful effect on bone regeneration, whereas the roles in osteoimmunomodulation have not been totally uncovered. Our study aimed to explore the immunomodulatory effect of DMOG/nSi-loaded fibrous membranes on periodontal bone remodeling. Materials and methodsThe fibrous membranes were prepared by incorporating DMOG and nSi into poly (lactic-co-glycolic acid) (PLGA) with electrospinning. The morphology features, surface chemical property and biocompatibility of DMOG/nSi-PLGA fibrous membranes were characterized. Thereafter, the fibrous membranes were implanted into rat periodontal defects, bone remodeling potential and immunomodulatory effect were evaluated by micro-computed tomography (micro-CT), histological evaluation and immunohistochemical analysis. ResultsDMOG/nSi-PLGA membranes possessed favorable physicochemical properties and biocompatibility. After the fibrous membranes implanted into periodontal defects, DMOG/nSi-PLGA membranes could relieve immuno-inflammatory responses of the defects (reduction of inflammatory cell infiltration, CD40L and CD11b-positive cells), increased CD206-positive M2 macrophages, and eventually facilitated periodontal bone regeneration. ConclusionDMOG/nSi-PLGA fibrous membranes exert protective effects during periodontal bone defect repairing, and steer immune response towards bone regeneration. Consequently, DMOG/nSi-PLGA fibrous membranes may serve as a promising scaffold in periodontal tissue engineering.

The expression and meaning of CD68, CD163, CD57, and IgG4 in granulomatous lobular mastitis.

The exact etiology and pathogenesis of granulomatous lobular mastitis (GLM) are yet to be illuminated. This study aimed to investigate CD68, CD163-positive M2 macrophages, CD57-positive natural killer (NK) cells, and IgG4 in GLM lesion tissue to explore their correlation with the occurrence and clinical features of GLM. Surgical pathologic specimens of GLM were collected from patients admitted to Hunan Provincial People's Hospital between October, 2014 and October 2015. Based on the postoperative pathological diagnosis, the tissues were divided into 3 groups: the experimental group (GLM, n=36), control group 1 (plasma cell mastitis, PCM, n=17), and control group 2 (breast cystic hyperplasia, n=10). Immunohistochemical staining was carried out using Elivision super testing to detect CD68, CD163, CD57, and IgG4 expression in the pathological tissue samples. The relationship between clinical parameters, including age, reproductive condition, nipple retraction, and tumor size, and the expressions of CD68, CD163, CD57, and IgG4 was analyzed. There was no obvious difference in the levels of CD68, CD163, and CD57 expression between the GLM group and the PCM group, although both groups had higher expression levels of expression than the breast cystic hyperplasia group (P<0.05). In the GLM group, the expression level of CD57 at 2 weeks-3 months was significantly higher than at ≤2 weeks (P<0.05). The expression level of CD57 in PCM patients >2 years after lactation was significantly higher than in patients ≤2 years after lactation (P<0.05). The level of IgG4 expression in GLM patients with nipple retraction was significantly higher than in those without nipple retraction (P<0.05). Inflammatory cells are closely linked to the occurrence of GLM and PCM. In our study, both the GLM and PCM groups had low expression of IgG4, but the expression level of IgG4 in GLM patients with inverted nipples was significantly higher than that in patients without inverted nipples. This suggests that there may be two different clinical subtypes of GLM. Furthermore, our research also found that NK cells can provide a basis for GLM clinical staging.

Generation of Novel Diagnostic and Therapeutic Exosomes to Detect and Deplete Protumorigenic M2 Macrophages.

Given their protumorigenic function and prevalence in most malignant tumors with lower survival; early detection, and intervention of CD206-positive M2 macrophages may boost the clinical outcome. To determine in vivo distribution of M2 macrophages, 111In-oxine-based radiolabeling of the targeted exosomes is adopted. When these radiolabeled targeted exosomes are injected into breast tumor-bearing mice, exosomes accumulate at the periphery of the primary tumor, metastatic foci in the lungs, spleen, and liver. Ex vivo quantification of radioactivity also shows similar distribution. Injecting DiI dye-labeled exosomes into the same mice shows adherence of exosomes to the CD206-positive M2 macrophages on ex vivo fluorescent microscopy imaging. In addition, these engineered exosomes are utilized to carry the Fc portion of lgG2b with the intention of augmenting antibody-dependent cell-mediated cytotoxicity. It is demonstrated that M2 macrophage targeting therapeutic exosomes deplete M2 macrophages both in vitro and in vivo, and reduce tumor burden, increasing survival in a metastatic breast cancer model.

Sodium tanshinone IIA sulfonate restrains fibrogenesis through induction of senescence in mice with induced deep endometriosis

Research questionDoes sodium tanshinone IIA sulfonate (STS) induce cellular senescence in endometriotic lesions and thus restrict lesional development and fibrogenesis in a recently established mouse model of deep endometriosis? DesignProspective randomized animal experiment in which deep endometriosis was induced in female Balb/C mice, which were then randomly divided into three groups (low-dose STS, high-dose STS and inert vehicle control) and received treatment for 2 weeks. All mice were then sacrificed and their lesions excised and harvested. Lesion weight was quantified and all lesion samples were subjected to histochemical analysis of the extent of lesional fibrosis by Masson trichrome staining, and of cellular senescence by senescence-associated β-galactosidase (SA-β-gal), along with immunohistochemistry analyses of p53, CCN1, activate Salvador 1 (Sav1), hyaluronan synthase 2 (HAS2), survivin, granulocyte-macrophage colony-stimulating factor (GM-CSF) and CD163-positive M2 macrophages. Plasma P-selectin and hyaluronic acid levels were also quantified. Hotplate testing was also administered before the induction, then before and after treatment. ResultsSTS treatment resulted in significantly reduced lesion weight, stalled lesional fibrogenesis and improved hyperalgesia, seemingly through the induction of cellular senescence by activating p53, Sav1 and CCN1 while suppressing HAS2, survivin and GM-CSF, resulting in increased apoptosis and reduced lesional infiltration of alternatively activated macrophages. In addition, STS treatment significantly reduced the plasma concentration of P-selectin and hyaluronic acid, possibly leading to reduced lesional platelet aggregation. ConclusionsSTS appears to be a promising compound for treating endometriosis. The results suggest that senescence may restrict lesional progression and fibrogenesis, and targeting the senescence pathway may have desirable therapeutic potential.

Colonic M1 macrophage is associated with the prolongation of gastrointestinal motility and obesity in mice treated with vancomycin.

Gut microbiota plays a pivotal role in not only the gastrointestinal (GI) immune system but also GI motility and metabolism. Antibiotic treatments are likely to affect the gut flora and GI immune system, subsequently disturbing GI motility and body metabolism. In the present study, we investigated antibiotic-induced alterations of body metabolism and GI motility in association with the macrophage profile in the colon. Specific pathogen-free (SPF) mice (ICR; 6 weeks old; female) were orally administered vancomycin (0.2 mg/ml) in drinking water for 5 weeks, and subsequent changes in pathophysiology were observed. The expression of CD80 and CD163 was examined by immunohistochemistry and the expression of cytokines in colonic tissues was evaluated by reverse transcription-quantitative polymerase chain reaction. The gastrointestinal transit time (GITT) was measured by administration of carmine red (6% w/v) solution. In the vancomycin-treated SPF mice, significant increases in body weight, cecum weight and GITT were observed compared with the controls. The number of CD80-positive M1 macrophages and the expression of interferon-γ and interleukin-12 were significantly increased, whereas, the numbers of CD163-positive M2 macrophages in the mucosal and muscular layers were decreased in the colon of vancomycin-treated mice. GITT was positively correlated with the number of CD80-positive M1 macrophages in the colonic mucosa; however, was negatively correlated with the number of CD163-positive M2 macrophages in the mucosal and muscular layers. Therefore, it was suggested that antibiotic treatment affects body metabolism and GI motility, accompanied by alterations in macrophage polarization and cytokine profiles in the colon.