scholarly journals Macrophage Polarization in the Skin Lesion Caused by Neotropical Species of Leishmania sp

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Carmen M. Sandoval Pacheco ◽  
Gabriela V. Araujo Flores ◽  
Kadir Gonzalez ◽  
Claudia M. de Castro Gomes ◽  
Luiz F. D. Passero ◽  
...  

Macrophages play important roles in the innate and acquired immune responses against Leishmania parasites. Depending on the subset and activation status, macrophages may eliminate intracellular parasites; however, these host cells also can offer a safe environment for Leishmania replication. In this sense, the fate of the parasite may be influenced by the phenotype of the infected macrophage, linked to the subtype of classically activated (M1) or alternatively activated (M2) macrophages. In the present study, M1 and M2 macrophage subsets were analyzed by double-staining immunohistochemistry in skin biopsies from patients with American cutaneous leishmaniasis (ACL) caused by L. (L.) amazonensis, L. (V.) braziliensis, L. (V.) panamensis ,and L. (L.) infantum chagasi. High number of M1 macrophages was detected in nonulcerated cutaneous leishmaniasis (NUCL) caused by L. (L.) infantum chagasi ( M 1 = 112 ± 12 , M 2 = 43 ± 12 cells/mm2). On the other side, high density of M2 macrophages was observed in the skin lesions of patients with anergic diffuse cutaneous leishmaniasis (ADCL) ( M 1 = 195 ± 25 , M 2 = 616 ± 114 ), followed by cases of localized cutaneous leishmaniasis (LCL) caused by L. (L.) amazonensis ( M 1 = 97 ± 24 , M 2 = 219 ± 29 ), L. (V.) panamensis ( M 1 = 71 ± 14 , M 2 = 164 ± 14 ), and L. (V.) braziliensis ( M 1 = 50 ± 13 , M 2 = 53 ± 10 ); however, low density of M2 macrophages was observed in NUCL. The data presented herein show the polarization of macrophages in skin lesions caused by different Leishmania species that may be related with the outcome of the disease.

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Wenbo Zhao ◽  
Junxian Hu ◽  
Qingyi He

Abstract Background When multicystic vesicles (precursors of exosomes) are formed in cells, there are two results. One is decomposition by lysosomes, and the other is the generation of exosomes that are transported out through the transmembrane. On the other hand, M2 macrophages promote the formation of local vascularization and provide necessary support for the repair of bone defects. To provide a new idea for the treatment of bone defects, the purpose of our study was to investigate the effect of WKYMVm (Trp-Lys-Tyr-Met-Val-D-Met-NH2) peptide on the secretion of exosomes from murine bone marrow-derived MSCs (mBMSCs) and the effect of exosomes on the polarization of M2 macrophages. Methods The WKYMVm peptide was used to activate the formyl peptide receptor 2 (FPR2) pathway in mBMSCs. First, we used Cell Counting Kit-8 (CCK-8) to detect the cytotoxic effect of WKYMVm peptide on mBMSCs. Second, we used western blotting (WB) and quantitative real-time polymerase chain reaction (qRT-PCR) to detect the expression of interferon stimulated gene 15 (ISG15) and transcription factor EB (TFEB) in mBMSCs. Then, we detected lysosomal activity using a lysozyme activity assay kit. Third, we used an exosome extraction kit and western blotting to detect the content of exosomes secreted by mBMSCs. Fourth, we used immunofluorescence and western blotting to count the number of polarized M2 macrophages. Finally, we used an inhibitor to block miRNA-146 in exosomes secreted by mBMSCs and counted the number of polarized M2 macrophages. Results We first found that the WKYMVm peptide had no toxic effect on mBMSCs at a concentration of 1 μmol/L. Second, we found that when the FPR2 pathway was activated by the WKYMVm peptide in mBMSCs, ISG15 and TFEB expression was decreased, leading to increased secretion of exosomes. We also found that lysosomal activity was decreased when the FPR2 pathway was activated by the WKYMVm peptide in mBMSCs. Third, we demonstrated that exosomes secreted by mBMSCs promote the polarization of M2 macrophages. Moreover, all these effects can be blocked by the WRWWWW (WRW4, H-Trp-Arg-Trp-Trp-Trp-Trp-OH) peptide, an inhibitor of the FPR2 pathway. Finally, we confirmed the effect of miRNA-146 in exosomes secreted by mBMSCs on promoting the polarization of M2 macrophages. Conclusion Our findings demonstrated the potential value of the WKYMVm peptide in promoting the secretion of exosomes by mBMSCs and eventually leading to M2 macrophage polarization. We believe that our study could provide a research basis for the clinical treatment of bone defects.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Yong You ◽  
Xiaoqing Zhang ◽  
Xiao Wang ◽  
Dan Yue ◽  
Fanxiang Meng ◽  
...  

This study was to identify functions of ILC2, a newly found innate lymphoid cell which mainly locates in mucosa organs like lungs and intestines, in IBD. We injected rIL-33 protein to C57/BL6 mouse to explore how IL-33 induces ILC2 proliferation. The results showed that ILC2 reached a proliferation peak at day 5 and expressed multiple surface markers like CD127, C-kit, CD69, CD44, ST2, CD27, DR3, MHCII, and CD90.2. ILC2 also expressed high quantity of IL-13 and IL-5 and few IL-17A which indicates a potentially immunological function in IBD development. Afterwards, we transferred sort purified ILC2 to Rag1-/- mouse given DSS to induce acute colitis in order to explore the innate function of ILC2. Data showed that ILC2 alleviates DSS-induced acute innate colitis by repairing epithelial barrier and restore body weight. Furthermore, we found that ILC2 can cause macrophages polarizing to M2 macrophages in the gut. Therefore, we concluded that ILC2 played a therapeutic role in mouse acute colitis.


2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi259-vi259
Author(s):  
Lili Chen ◽  
Ming Li

Abstract Guanylate binding protein 1 (GBP1) is an interferon-inducible large GTPase which plays a key role in tumor development, but the molecular mechanism is poorly understood. Here we investigated whether GBP1 could influence the tumor microenvironment in glioblastoma, the most common and malignant brain tumor. We found that forced expression of GBP1 in glioblastoma cells induced macrophage polarization toward an M2 phenotype via upregulating Chemokine (C-C motif) ligand 2 (CCL2). CCL2 acted via its receptor C-C chemokine receptor 2 (CCR2) to enhance macrophage cell migration in vitro. The M2 macrophages in turn promoted glioblastoma cell proliferation and migration. The orthotopic mouse model showed that GBP1 recruited M2 macrophages into tumor to promote glioblastoma progression, and targeting CCL2/CCR2 signaling axis with a small molecule inhibitor RS504393 led to decreased macrophage attraction and M2 polarization and a significant tumor growth retardation and prolonged survival of tumor-bearing mice. Clinically, GBP1 expression positively correlated with M2 macrophage numbers and CCL2 expression in glioblastoma. Taken together, our results reveal that GBP1 modulates the tumor immune microenvironment through CCL2 induction to promote glioblastoma infiltrating growth, and targeting tumor-associated macrophages may represent a new therapeutic strategy against glioblastoma.


2020 ◽  
pp. 153537022097232
Author(s):  
Lisha Li ◽  
Xuemin Qiu ◽  
Na Zhang ◽  
Yan Sun ◽  
Yan Wang ◽  
...  

A loss-of-function mutation in the Lrp5 gene in mice leads to a low bone mass disorder due to the inhibition of the canonical Wnt signaling pathway; however, the role of bone marrow microenvironment in mice with this mutation remains unclear. In this study, we evaluated proliferation and osteogenic potential of mouse osteoblasts using the MTT assay and Alizarin red staining. The levels of alkaline phosphatase, tartrate-resistant acid phosphatase, and adiponectin in culture supernatants were measured using the enzyme-linked immunosorbent assay. Osteoclast bone resorbing activity was evaluated by toluidine staining and the number and area of bone resorption pits were determined. We observed increased osteogenesis in osteoblasts co-cultured with the BM-derived myeloid cells compared to the osteoblasts cultured alone. Mice with global Lrp5 deletion had a relatively higher bone density compared to the mice carrying osteoblast/osteocyte-specific Lrp5 deletion. An increased frequency of M2 macrophages and reduced expression of inflammatory cytokines were detected in the myeloid cells derived from the bone marrow of mice with global Lrp5 deletion. Higher adipogenic potential and elevated levels of adiponectin in the global Lrp5 deletion mice contributed to the preferential M2 macrophage polarization. Here, we identified a novel systemic regulatory mechanism of bone formation and degradation in mice with global Lrp5 deletion. This mechanism depends on a crosstalk between the adipocytes and M2 macrophages in the bone marrow and is responsible for partly rescuing osteopenia developed as a result of decreased Wnt signaling.


2019 ◽  
Vol 20 (19) ◽  
pp. 4966 ◽  
Author(s):  
Tedesco ◽  
Scattolini ◽  
Albiero ◽  
Bortolozzi ◽  
Avogaro ◽  
...  

Macrophages are highly plastic and dynamic cells that exert much of their function through phagocytosis. Phagocytosis depends on a coordinated, finely tuned, and compartmentalized regulation of calcium concentrations. We examined the role of mitochondrial calcium uptake and mitochondrial calcium uniporter (MCU) in macrophage polarization and function. In primary cultures of human monocyte-derived macrophages, calcium uptake in mitochondria was instrumental for alternative (M2) macrophage polarization. Mitochondrial calcium uniporter inhibition with KB-R7943 or MCU knockdown, which prevented mitochondrial calcium uptake, reduced M2 polarization, while not affecting classical (M1) polarization. Challenging macrophages with E. coli fragments induced spikes of mitochondrial calcium concentrations, which were prevented by MCU inhibition or silencing. In addition, mitochondria remodelled in M2 macrophages during phagocytosis, especially close to sites of E. coli internalization. Remarkably, inhibition or knockdown of MCU significantly reduced the phagocytic capacity of M2 macrophages. KB-R7943, which also inhibits the membrane sodium/calcium exchanger and Complex I, reduced mitochondria energization and cellular ATP levels, but such effects were not observed with MCU silencing. Therefore, phagocytosis inhibition by MCU knockdown depended on the impaired mitochondrial calcium buffering rather than changes in mitochondrial and cellular energy status. These data uncover a new role for MCU in alternative macrophage polarization and phagocytic activity.


2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Senlin Zhao ◽  
Yushuai Mi ◽  
Bingjie Guan ◽  
Binbin Zheng ◽  
Ping Wei ◽  
...  

Abstract Background Mounting evidence has demonstrated the vital importance of tumor-associated macrophages (TAMs) and exosomes in the formation of the premetastatic niche. However, the molecular mechanisms by which tumor-derived exosomal miRNAs interact with TAMs underlying premetastatic niche formation and colorectal cancer liver metastasis (CRLM) remain largely unknown. Methods Transmission electron microscopy and differential ultracentrifugation were used to verify the existence of exosomes. In vivo and in vitro assays were used to identify roles of exosomal miR-934. RNA pull-down assay, dual-luciferase reporter assay, etc. were applied to clarify the mechanism of exosomal miR-934 regulated the crosstalk between CRC cells and M2 macrophages. Results In the present study, we first demonstrated the aberrant overexpression of miR-934 in colorectal cancer (CRC), especially in CRLM, and its correlation with the poor prognosis of CRC patients. Then, we verified that CRC cell-derived exosomal miR-934 induced M2 macrophage polarization by downregulating PTEN expression and activating the PI3K/AKT signaling pathway. Moreover, we revealed that hnRNPA2B1 mediated miR-934 packaging into exosomes of CRC cells and then transferred exosomal miR-934 into macrophages. Interestingly, polarized M2 macrophages could induce premetastatic niche formation and promote CRLM by secreting CXCL13, which activated a CXCL13/CXCR5/NFκB/p65/miR-934 positive feedback loop in CRC cells. Conclusions These findings indicate that tumor-derived exosomal miR-934 can promote CRLM by regulating the crosstalk between CRC cells and TAMs. These findings reveal a tumor and TAM interaction in the metastatic microenvironment mediated by tumor-derived exosomes that affects CRLM. The present study also provides a theoretical basis for secondary liver cancer.


Author(s):  
Yong Fan ◽  
Yanjie Hao ◽  
Dai Gao ◽  
Lan Gao ◽  
Guangtao Li ◽  
...  

Pulmonary arterial hypertension (PAH) is a fatal disease characterized by vascular remodeling and chronic inflammation. Macrophages are the key orchestrators of inflammatory and repair responses, and have been demonstrated to be vital in the pathogenesis of PAH. However, specific phenotype of macrophage polarization (M1 & M2 macrophage) in the development of PAH and the underlying mechanisms how they work are still largely unclear. A rat model of monocrotaline (MCT) induced PAH was used. Hemodynamic analysis and histopathological experiments were conducted at day 3, 7, 14, 21 and 28, respectively. In PAH rat lung tissue, confocal microscopic images showed that CD68+NOS2+ M1-like macrophages were remarkably infiltrated on early stage, but dramatically decreased in mid-late stage. Meanwhile, CD68+CD206+ M2-like macrophages in lung tissue accumulated gradually since day 7 to day 28, and the relative ratio of M2/M1 macrophage increased over time. Results detected by western blot and immunohistochemistry were consistent. Further vitro functional studies revealed the possible mechanism involved in this pathophysiological process. By using Transwell co-culture system, it was found that M1 macrophages induced endothelial cell apoptosis, while M2 macrophages significantly promoted proliferation of both endothelial cell and smooth muscle cell. These data preliminarily demonstrated a temporal dynamic change of macrophage M1/M2 polarization status in the development of experimental PAH. M1 macrophages participated in the initial stage of inflammation by accelerating apoptosis of endothelial cell, while M2 macrophages predominated in the reparative stage of inflammation and the followed stage of aberrant tissue remodeling.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
K. Gonzalez ◽  
J. E. Calzada ◽  
C. E. P. Corbett ◽  
A. Saldaña ◽  
M. D. Laurenti

Localized cutaneous leishmaniasis (LCL) caused by Leishmania (Viannia) panamensis is an endemic disease in Panama. This condition causes ulcerated skin lesions characterized by a mixed Th1/Th2 immune response that is responsible for disease pathology. However, the maintenance of the in situ inflammatory process involves other elements, such as Th17 and inflammasome responses. Although these processes are associated with parasite elimination, their role in the increase in disease pathology cannot be discarded. Thus, the role in Leishmania infection is still unclear. In this sense, the present study aimed at characterizing the Th17 and inflammasome responses in the skin lesions of patients with LCL caused by L. (V.) panamensis to help elucidate the pathogenesis of this disease in Panama. Th17 and inflammasome responses were evaluated by immunohistochemistry (IHQ) in 46 skin biopsies from patients with LCL caused by L. (V.) panamensis. The Th17 immune response was assessed using CD3, CD4, RoRγt, IL-17, IL-6, IL-23, and TGF-β1 antibodies, and the inflammasome response was assessed by IL-1β, IL-18, and caspase-1 antibodies. The presence of the Th17 and inflammasome responses was evidenced by a positive reaction for all immunological markers in the skin lesions. An inverse correlation between the density of amastigotes and the density of RoRγt+, IL-17+, IL-1β+, and caspase-1+ cells was observed, but no correlation between Th17 and the inflammasome response with evolutionary disease pathology was reported. These data showed the participation of Th17 cells and the inflammasome in the inflammatory response of the skin lesions of LCL caused by L. (V.) panamensis infection. These results suggest a role in the control of tissue parasitism of IL-17 and the activation of the NLRP3 inflammasome dependent on IL-1β but cannot exclude their role in the development of disease pathology.


Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1303 ◽  
Author(s):  
Alexandra Pritchard ◽  
Sultan Tousif ◽  
Yong Wang ◽  
Kenneth Hough ◽  
Saad Khan ◽  
...  

Cellular cross-talk within the tumor microenvironment (TME) by exosomes is known to promote tumor progression. Tumor promoting macrophages with an M2 phenotype are suppressors of anti-tumor immunity. However, the impact of tumor-derived exosomes in modulating macrophage polarization in the lung TME is largely unknown. Herein, we investigated if lung tumor-derived exosomes alter transcriptional and bioenergetic signatures of M0 macrophages and polarize them to an M2 phenotype. The concentration of exosomes produced by p53 null H358 lung tumor cells was significantly reduced compared to A549 (p53 wild-type) lung tumor cells, consistent with p53-mediated regulation of exosome production. In co-culture studies, M0 macrophages internalized tumor-derived exosomes, and differentiated into M2 phenotype. Importantly, we demonstrate that tumor-derived exosomes enhance the oxygen consumption rate of macrophages, altering their bioenergetic state consistent with that of M2 macrophages. In vitro co-cultures of M0 macrophages with H358 exosomes demonstrated that exosome-induced M2 polarization may be p53 independent. Murine bone marrow cells and bone marrow-derived myeloid-derived suppressor cells (MDSCs) co-cultured with lewis lung carcinoma (LLC)-derived exosomes differentiated to M2 macrophages. Collectively, these studies provide evidence for a novel role for lung tumor-exosomes in M2 macrophage polarization, which then offers new therapeutic targets for immunotherapy of lung cancer.


2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Yohei Kawai ◽  
Yuji Narita ◽  
Aika Yamawaki-Ogata ◽  
Akihiko Usui ◽  
Kimihiro Komori

Background. The pathogenesis of abdominal aortic aneurysm (AAA) is characterized by atherosclerosis with chronic inflammation in the aortic wall. Montelukast is a selective cys-LT 1 receptor antagonist that can suppress atherosclerotic diseases. We evaluated the in vitro properties of montelukast and its in vivo activities in an angiotensin II–infused apolipoprotein E–deficient (apoE−/−) AAA mouse model. Methods. The mouse monocyte/macrophage cell line J774A.1 was used in vitro. M1 macrophages were treated with montelukast, and gene expressions of inflammatory cytokines were measured. Macrophages were cultured with montelukast, then gene expressions of arginase-1 and IL (interleukin)-10 were assessed by quantitative polymerase chain reaction, arginase-1 was measured by fluorescence-activated cell sorting, and IL-10 concentration was analyzed by enzyme-linked immunosorbent assay. In vivo, one group (Mont, n=7) received oral montelukast (10 mg/kg/day) for 28 days, and the other group (Saline, n=7) was given normal Saline as a control for the same period. Aortic diameters, activities of matrix metalloproteinases (MMPs), cytokine concentrations, and the number of M2 macrophages were analyzed. Results. Relative to control, montelukast significantly suppressed gene expressions of MMP-2, MMP-9, and IL-1β, induced gene expressions of arginase-1 and IL-10, enhanced the expression of the arginase-1 cell surface protein, and increased the protein concentration of IL-10. In vivo, montelukast significantly decreased aortic expansion (Saline vs Mont; 2.44 ± 0.15 mm vs 1.59 ± 0.20 mm, P<.01), reduced MMP-2 activity (Saline vs Mont; 1240 μM vs 755 μM, P<.05), and induced infiltration of M2 macrophages (Saline vs Mont; 7.51 % vs 14.7 %, P<.05). Conclusion. Montelukast induces M2 macrophage polarization and prevents AAA formation in apoE−/− mice.


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