Dataset Information

Origin of M2 Mϕ and its macrophage polarization by TGF-β in a mice intervertebral injury model.

ABSTRACT:

Introduction

Studies have identified the presence of M1 and M2 macrophages (Mϕ) in injured intervertebral discs (IVDs). However, the origin and polarization-regulatory factor of M2 Mϕ are not fully understood. TGF-β is a regulatory factor for M2 polarization in several tissues. Here, we investigated the source of M2 Mϕ and the role of TGF-β on M2 polarization using a mice disc-puncture injury model.

Methods

To investigate the origin of M2 macrophages, 30 GFP chimeric mice were created by bone marrow transplantation. IVDs were obtained from both groups on pre-puncture (control) and post-puncture days 1, 3, 7, and 14 and CD86 (M1 marker)- and CD206 (M2 marker)-positive cells evaluated by flow cytometry (n = 5 at each time point). To investigate the role of TGF-β on M2 polarization, TGF-β inhibitor (SB431542) was also injected on post-puncture days (PPD) 5 and 6 and CD206 expression was evaluated on day 7 by flow cytometry (n = 5) and real time PCR (n = 10).

Results

The proportion of CD86⁺ Mϕ within the GFP+ population was significantly increased at PPD 1, 3, 7, and 14 compared to control. CD206-positive cells in GFP-populations were significantly increased on PPD 7 and 14. In addition, the percentage of CD206-positive cells was significantly higher in GFP-populations than in GFP+ populations. TGF-β inhibitor reduced CD206-positive cells and Cd206 expression at 7 days after puncture.

Conclusion

Our findings suggest that M2 Mϕ following IVD injury may originate from resident Mϕ. TGF-β is a key factor for M2 polarization of macrophages following IVD injury.

SUBMITTER: Kawakubo A

PROVIDER: S-EPMC9174651 | biostudies-literature | 2022 Jan-Dec

REPOSITORIES: biostudies-literature

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Publications

Origin of M2 Mϕ and its macrophage polarization by TGF-β in a mice intervertebral injury model.

Kawakubo Ayumu A Miyagi Masayuki M Yokozeki Yuji Y Nakawaki Mitsufumi M Takano Shotaro S Satoh Masashi M Itakura Makoto M Inoue Gen G Takaso Masashi M Uchida Kentaro K

International journal of immunopathology and pharmacology 20220101

<h4>Introduction</h4>Studies have identified the presence of M1 and M2 macrophages (Mϕ) in injured intervertebral discs (IVDs). However, the origin and polarization-regulatory factor of M2 Mϕ are not fully understood. TGF-β is a regulatory factor for M2 polarization in several tissues. Here, we investigated the source of M2 Mϕ and the role of TGF-β on M2 polarization using a mice disc-puncture injury model.<h4>Methods</h4>To investigate the origin of M2 macrophages, 30 GFP chimeric mice were cre ...[more]

PMID: 35592891

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Project description:IntroductionMacrophage phenotypes have been linked to progression and prognosis of cutaneous melanoma. However, the association between Warburg effect in A375 melanoma and macrophages polarization, as well as the underlying mechanisms, remains less well documented.ObjectiveThe present study aimed to investigate the effect of lactate derived from A375 melanoma on macrophage polarization, melanoma phenotype responses and the underlying mechanisms.MethodsFlow cytometry was performed to evaluate the expression of M1 and M2 markers, cell cycle and apoptosis. Levels of transforming growth factor β (TGF-β) and tumor necrosis factor α (TNF-α) were determined with enzyme-linked immunosorbent assay (ELISA) kit. Proliferation and invasion were assessed by CCK8 and transwell assays, respectively. The extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) were analyzed using an XF96 extracellular flux analyzer. Protein expressions were determined by Western blotting.ResultsOur results revealed that melanoma A375 conditioned medium (A375-CM) induced peripheral blood mononuclear cells (PBMCs) to polarize toward anti-inflammatory M2 macrophages. M2 markers CD206 and ARG1 expression increased, as did TGF-β secretion. Conversely, M1 marker CD68 expression decreased. Furthermore, hypoxia promoted macrophage M2 polarization induced by A375-CM. Elevated lactate level in PIG1-conditioned medium (PIG1-CM) induced M2 polarization, whereas the lactate transport inhibitor AZD3965 suppressed this effect in PBMCs cultured with A375-CM. Additionally, lactate derived from melanoma regulated M1/M2 polarization by the tricarboxylic acid (TCA) cycle instead of glycolysis. Significantly, polarized macrophages altered melanoma phenotypes including proliferation, clone formation, cell cycle, apoptosis, migration and invasion via TCA cycle and TGF-β.ConclusionOur data collectively demonstrate that lactate derived from melanoma facilitates polarization of M2 macrophages, which subsequently leads to modifications in melanoma phenotypes via TCA cycle and TGF-β signaling.

Dataset Information

Origin of M2 Mϕ and its macrophage polarization by TGF-β in a mice intervertebral injury model.

Introduction

Methods

Results

Conclusion

Publications

Origin of M2 Mϕ and its macrophage polarization by TGF-β in a mice intervertebral injury model.

Similar Datasets

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