The ability to suppress macrophage-mediated inflammation in orbital fat stem cells is controlled by miR-671-5p

Abstract

IntroductionOur previous works demonstrated that systemic orbital fat-derived stem cell (OFSC) transplantation was effective in ameliorating lipopolysaccharide (LPS)-induced extensive acute lung injury (ALI) in vivo mainly through paracrine regulation of macrophage-mediated cytokine-storm. In this study, we explore the molecular mechanism(s) of OFSCs regulating macrophage activity in a cytokine-inducible fashion.MethodsLPS (100 ng/ml)-activated macrophages were treated by conditioned medium from OFSCs (OFSCs-CM) or non-contact cultured with OFSCs for 6 hours. The potency of OFSCs on macrophage proliferation and pro-inflammation ability were determined. Expression levels of pro-inflammatory cytokines in macrophages, inducible immuno-modulatory factors in OFSCs, were investigated. Deep sequencing analysis as well as interaction between microRNA (miRNA) and genes of immuno-modulators in OFSCs induced by activated macrophages was predicted by miRTar. Transfection of miRNA inhibitor into OFSCs was performed. Real-time RT-PCR and transplantation of OFSCs into mice with LPS-induced ALI confirmed the in vitro and in vivo mechanism.ResultsThe paracrine effect of OFSCs on inhibition of macrophage pro-inflammatory cytokine release was more potent than induction of macrophage G0/G1 cell cycle arrest. OFSCs-CM suppressed LPS-induced inducible nitric oxide synthetase and the pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1 alpha, and IL-1 beta expression in macrophages. Under non-contact culture, LPS-activated macrophages effectively triggered the expression of soluble immuno-modulating factors in OFSCs, i.e., IL-10, IL-1 receptor antagonist (IL-1 RA), indoleamine 2,3-dioxygenase, and soluble TNF receptor type II (sTNF RII). Under miRTar prediction, miR-671-5p was identified as a critical microRNA in regulation of multiple immune-modulating factors in OFSCs response to macrophages. The baseline level of miR-671-5p was high in OFSCs, and down-regulation of miR-671-5p upon co-culture with activated macrophages was observed. MiR-671-5p inhibitor transfection into OFSCs selectively enhanced the IL-1 RA and sTNF RII expressions. In addition, inhibition of miR-671-5p in OFSCs enhanced the anti-inflammatory ability against LPS-induced ALI.ConclusionThe paracrine effect of OFSCs inhibits the pro-inflammatory ability and proliferation of macrophages. The immune-modulation capacity of OFSCs can be triggered by activated macrophages, and down-regulation of miR-671-5p enhances OFSC immuno-modulation ability by up-regulating IL-1 RA and sTNF RII expression.

Niche-Dependent Regulations of Metabolic Balance in High-Fat Diet–Induced Diabetic Mice by Mesenchymal Stromal Cells

“…It is known that release of soluble immune-modulatory factors from MSCs is induced by TNF-a, IL-1, and interferon-g (IFN-g) (35,36). Recently, we and others report that MSCs exert their anti-inflammatory action via producing IDO, IL-10, IL-1 RA, and sTNF RII by themselves and reducing TNF-a and IL-1 level from macrophages (27,37). In a coculture study, MSCs show their protective effect on both islet cells and b-cells against IFN-g-, TNF-a-, and IL-1b-induced apoptosis (38).…”

“…We have previously reported that indoleamine 2,3-dioxygenase (IDO), human IL-10 (hIL-10), soluble TNF receptor II (sTNF RII), and IL-1 RA are inducible immune modulators produced by human MSCs in response to the stimulation of macrophage-produced IL-1a, IL-1b, and TNF-a (27). We have also demonstrated that in a murine model of type 1 diabetes, systemic transplantation of MSCs regulates blood glucose homeostasis by differentiation into insulin-producing cells in liver when islet cells are totally depleted in the pancreas, and such heterotopic engraftment is not observed in nondiabetic mice (28).…”

Mesenchymal stem cells prolong survival and prevent lethal complications in a porcine model of fulminant liver failure

“…MSCs can be harvested from a number of tissue sources including adipose tissues . Adipose tissue‐derived MSCs can be obtained with ease and used allogenically, The abundant secreted growth factors and cytokines not only promote blood vessel formation and endothelial‐cell proliferation, but are also anti‐inflammatory . MSCs are immunologically privileged because they lack major histocompatibility complex (MHC) II expression.…”

“…[20][21][22][23] Adipose tissue-derived MSCs can be obtained with ease and used allogenically, 24 The abundant secreted growth factors and cytokines not only promote blood vessel formation and endothelial-cell proliferation, 25 but are also anti-inflammatory. [26][27][28] MSCs are immunologically privileged because they lack major histocompatibility complex (MHC) II expression. In addition, human MSC-derived hepatocytes do not express MHCII in vitro.…”

Local Injection of Mesenchymal Stem Cells Protects Testicular Torsion-induced Germ Cell Injury

“…Orbital fat-derived stem cells (OFSCs) are MSCs isolated from human orbital fat tissue [14] and their therapeutic effects on acute tissue injury have been demonstrated via paracrine tissue support, immunomodulation, and differentiation ability in our previous experimental studies [15][16][17]. In this study, rats received surgery with 720°of unilateral testicular torsion for 3 hours, and local injection of OFSCs 30 minutes before surgical detorsion was performed.…”