Upadhya Raghavendra, Madhu Leelavathi N, Rao Shama, Shetty Ashok K
Department of Molecular and Cellular Medicine, Institute for Regenerative Medicine, Texas A&M University College of Medicine, College Station, TX, United States.
Front Mol Neurosci. 2022 May 17;15:845542. doi: 10.3389/fnmol.2022.845542. eCollection 2022.
Extracellular vesicles (EVs) shed by human-induced pluripotent stem cell (hiPSC)-derived neural stem cells (hNSC-EVs) have shown potent antiinflammatory properties in a mouse macrophage assay and a mouse model of acute neuroinflammation. They can also quickly permeate the entire brain after intranasal administration, making them attractive as an autologous or allogeneic off-the-shelf product for treating neurodegenerative diseases. However, their ability to modulate activated human microglia and specific proteins and miRNAs mediating antiinflammatory effects of hNSC-EVs are unknown. We investigated the proficiency of hNSC-EVs to modulate activated human microglia and probed the role of the protein pentraxin 3 (PTX3) and the miRNA miR-21-5p within hNSC-EVs in mediating the antiinflammatory effects. Mature microglia generated from hiPSCs (iMicroglia) expressed multiple microglia-specific markers. They responded to lipopolysaccharide (LPS) or interferon-gamma challenge by upregulating tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) mRNA expression and protein release. iMicroglia also exhibited proficiency to phagocytose amyloid-beta (Aβ). The addition of hNSC-EVs decreased TNF-α and IL-1β mRNA expression and the release of TNF-α and IL-1β by LPS-stimulated iMicroglia (proinflammatory human Microglia). However, the antiinflammatory activity of hNSC-EVs on LPS-stimulated microglia was considerably diminished when the PTX3 or miR-21-5p concentration was reduced in EVs. The results demonstrate that hNSC-EVs are proficient for modulating the proinflammatory human microglia into non-inflammatory phenotypes, implying their utility to treat neuroinflammation in neurodegenerative diseases. Furthermore, the role of PTX3 and miR-21-5p in the antiinflammatory activity of hNSC-EVs provides a new avenue for improving the antiinflammatory effects of hNSC-EVs through PTX3 and/or miR-21-5p overexpression.
人诱导多能干细胞（hiPSC）来源的神经干细胞分泌的细胞外囊泡（hNSC-EVs）在小鼠巨噬细胞试验和急性神经炎症小鼠模型中已显示出强大的抗炎特性。鼻内给药后，它们还能迅速渗透到整个大脑，这使其作为一种用于治疗神经退行性疾病的自体或异体现成产品具有吸引力。然而，它们调节活化的人小胶质细胞的能力以及介导hNSC-EVs抗炎作用的特定蛋白质和微小RNA（miRNA）尚不清楚。我们研究了hNSC-EVs调节活化的人小胶质细胞的能力，并探讨了hNSC-EVs中蛋白五聚素3（PTX3）和miRNA miR-21-5p在介导抗炎作用中的作用。由hiPSC产生的成熟小胶质细胞（i小胶质细胞）表达多种小胶质细胞特异性标志物。它们通过上调肿瘤坏死因子-α（TNF-α）和白细胞介素-1β（IL-1β）mRNA表达及蛋白质释放来响应脂多糖（LPS）或干扰素-γ刺激。i小胶质细胞还表现出吞噬β-淀粉样蛋白（Aβ）的能力。添加hNSC-EVs可降低LPS刺激的i小胶质细胞（促炎人小胶质细胞）中TNF-α和IL-1β mRNA表达以及TNF-α和IL-1β的释放。然而，当EVs中PTX3或miR-21-5p浓度降低时，hNSC-EVs对LPS刺激的小胶质细胞的抗炎活性显著降低。结果表明，hNSC-EVs能够有效地将促炎人小胶质细胞调节为非炎症表型，这意味着它们在治疗神经退行性疾病中的神经炎症方面具有实用性。此外，PTX3和miR-21-5p在hNSC-EVs抗炎活性中的作用为通过PTX3和/或miR-21-5p过表达来提高hNSC-EVs的抗炎效果提供了一条新途径。
