Department of Plastic Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, United States.
McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States.
Front Immunol. 2020 May 6;11:826. doi: 10.3389/fimmu.2020.00826. eCollection 2020.
Mesenchymal stromal cell (MSC)-based cytotherapies fuel the hope for reduction of chronic systemic immunosuppression in allotransplantation, and our group has previously shown this capability for both swine and human cells. MSCs harvested from distinct anatomical locations may have different behavior and lead to different outcomes in both preclinical research and human trials. To provide an effective reference for cell therapy studies, we compared human and porcine MSCs from omental fat (O-ASC), subcutaneous fat (SC-ASC) and bone marrow (BM-MSC) under rapid culture expansion with endothelial growth medium (EGM). MSCs isolated from pigs and deceased human organ donors were compared for yield, viability, cell size, population doubling times (PDT), surface marker expression and differentiation potential after rapid expansion with EGM. Immunosuppressant toxicity on MSCs was investigated for four different standard immunosuppressive drugs. Immunomodulatory function was compared in mixed lymphocyte reaction assays (MLR) with/without immunosuppressive drug influence. Human and porcine omental fat yielded significantly higher cell numbers than subcutaneous fat. Initial PDT was significantly shorter in ASCs than BM-MSCs and similar thereafter. Viability was reduced in BM-MSCs. Porcine MSCs were positive for CD29, CD44, CD90, while human MSCs expressed CD73, CD90 and CD105. All demonstrated confirmed adipogenic differentiation capacity. Cell sizes were comparable between groups and were slightly larger in human cells. Rapamycin revealed slight, mycophenolic acid strong and significant dose-dependent toxicity on viability/proliferation of almost all MSCs at therapeutic concentrations. No relevant toxicity was found for Tacrolimus and Cyclosporin A. Immunomodulatory function was dose-dependent and similar between groups. Immunosuppressants had no significant adverse effect on MSC immunomodulatory function. MSCs from different harvest locations and donor species differ in terms of isolation yields, viability, PDT, and size. We did not detect relevant differences in immunomodulatory function with or without the presence of immunosuppressants. Human and pig O-ASC, SC-ASC and BM-MSC share similar immunomodulatory function and warrant confirmation in large animal studies. These findings should be considered in preclinical and clinical MSC applications.
间充质基质细胞（MSC）为基础的细胞疗法为减少同种异体移植中的慢性全身免疫抑制带来了希望，我们的研究小组之前已经证明了这一能力在猪和人类细胞中都存在。从不同解剖部位采集的间充质基质细胞可能具有不同的行为，并在临床前研究和人体试验中导致不同的结果。为了为细胞治疗研究提供有效的参考，我们比较了来自大网膜脂肪（O-ASC）、皮下脂肪（SC-ASC）和骨髓（BM-MSC）的人类和猪的间充质基质细胞，在快速培养中使用内皮生长培养基（EGM）。我们比较了从猪和已故人类器官供体中分离的间充质基质细胞，以确定其在快速培养中使用 EGM 后的产量、活力、细胞大小、倍增时间（PDT）、表面标记表达和分化潜能。研究了四种不同标准免疫抑制剂药物对间充质基质细胞的免疫抑制毒性。在混合淋巴细胞反应（MLR）实验中比较了免疫调节功能，有无免疫抑制剂的影响。人类和猪的大网膜脂肪产生的细胞数量明显高于皮下脂肪。ASCs 的初始 PDT 明显短于 BM-MSCs，此后相似。BM-MSCs 的活力降低。猪间充质基质细胞表达 CD29、CD44、CD90，而人类间充质基质细胞表达 CD73、CD90 和 CD105。所有细胞均证实具有确认的成脂分化能力。细胞大小在各组之间相当，人类细胞稍大。雷帕霉素在治疗浓度下对几乎所有间充质基质细胞的活力/增殖显示出轻微、霉酚酸酸强和显著的剂量依赖性毒性。他克莫司和环孢素 A 未发现相关毒性。免疫调节功能呈剂量依赖性，各组之间相似。免疫抑制剂对间充质基质细胞免疫调节功能无显著不良影响。来自不同采集部位和供体物种的间充质基质细胞在分离产量、活力、PDT 和大小方面存在差异。我们没有发现在存在或不存在免疫抑制剂的情况下，间充质基质细胞的免疫调节功能存在相关差异。人类和猪的 O-ASC、SC-ASC 和 BM-MSC 具有相似的免疫调节功能，值得在大动物研究中进一步证实。这些发现应在临床前和临床 MSC 应用中加以考虑。
