Urology Department, Urology and Nephrology Center, Mansoura, Egypt.
Biotechnology Department, Urology and Nephrology Center, Mansoura, Egypt.
Stem Cell Res Ther. 2022 Jul 26;13(1):350. doi: 10.1186/s13287-022-03048-y.
The purpose of this study was to investigate allogenic immune responses following the transplantation of insulin-producing cells (IPCs) differentiated from human adipose tissue-derived stem cells (hAT-MSCs) into humanized mice.
hAT-MSCs were isolated from liposuction aspirates obtained from HLA-A2-negative healthy donors. These cells were expanded and differentiated into IPCs. HLA-A2-positive humanized mice (NOG-EXL) were divided into 4 groups: diabetic mice transplanted with IPCs, diabetic but nontransplanted mice, nondiabetic mice transplanted with IPCs and normal untreated mice. Three million differentiated cells were transplanted under the renal capsule. Animals were followed-up to determine their weight, glucose levels (2-h postprandial), and human and mouse insulin levels. The mice were euthanized 6-8 weeks posttransplant. The kidneys were explanted for immunohistochemical studies. Blood, spleen and bone marrow samples were obtained to determine the proportion of immune cell subsets (CD4, CD8, CD16, CD19 and CD69), and the expression levels of HLA-ABC and HLA-DR.
Following STZ induction, blood glucose levels increased sharply and were then normalized within 2 weeks after cell transplantation. In these animals, human insulin levels were measurable while mouse insulin levels were negligible throughout the observation period. Immunostaining of cell-bearing kidneys revealed sparse CD45 cells. Immunolabeling and flow cytometry of blood, bone marrow and splenic samples obtained from the 3 groups of animals did not reveal a significant difference in the proportions of immune cell subsets or in the expression levels of HLA-ABC and HLA-DR.
Transplantation of IPCs derived from allogenic hAT-MSCs into humanized mice was followed by a muted allogenic immune response that did not interfere with the functionality of the engrafted cells. Our findings suggest that such allogenic cells could offer an opportunity for cell therapy for insulin-dependent diabetes without immunosuppression, encapsulation or gene manipulations.
本研究旨在探讨人脂肪组织来源的干细胞（hAT-MSCs）分化的胰岛素产生细胞（IPCs）移植入人源化小鼠后引发的同种异体免疫反应。
从 HLA-A2 阴性健康供者的吸脂术抽吸物中分离 hAT-MSCs。将这些细胞扩增并分化为 IPCs。将 HLA-A2 阳性的人源化小鼠（NOG-EXL）分为 4 组：移植 IPCs 的糖尿病小鼠、未移植但患有糖尿病的小鼠、移植 IPCs 的非糖尿病小鼠和未经处理的正常小鼠。将 300 万个分化细胞移植到肾包膜下。动物进行随访以确定其体重、血糖水平（餐后 2 小时）以及人胰岛素和鼠胰岛素水平。移植后 6-8 周处死小鼠。取出肾脏进行免疫组织化学研究。采集血液、脾脏和骨髓样本以确定免疫细胞亚群（CD4、CD8、CD16、CD19 和 CD69）的比例以及 HLA-ABC 和 HLA-DR 的表达水平。
在 STZ 诱导后，血糖水平急剧升高，然后在细胞移植后 2 周内恢复正常。在这些动物中，可测量到人胰岛素水平，而整个观察期间鼠胰岛素水平可忽略不计。携带细胞的肾脏的免疫染色显示稀疏的 CD45 细胞。对来自 3 组动物的血液、骨髓和脾样本进行免疫标记和流式细胞术分析，未发现免疫细胞亚群比例或 HLA-ABC 和 HLA-DR 的表达水平有显著差异。
将源自同种异体 hAT-MSCs 的 IPCs 移植入人源化小鼠后，引发的同种异体免疫反应较弱，不会干扰植入细胞的功能。我们的研究结果表明，这种同种异体细胞为无需免疫抑制、囊封或基因操作的胰岛素依赖性糖尿病的细胞治疗提供了机会。
