Beta Cell Neogenesis (BENE), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium.
Department of Paediatrics, Division of Paediatric Endocrinology, Ghent University, Ghent, Belgium.
Diabetologia. 2018 Aug;61(8):1804-1810. doi: 10.1007/s00125-018-4646-7. Epub 2018 May 22.
AIMS/HYPOTHESIS: The initial avascular period following islet transplantation seriously compromises graft function and survival. Enhancing graft revascularisation to improve engraftment has been attempted through virus-based delivery of angiogenic triggers, but risks associated with viral vectors have hampered clinical translation. In vitro transcribed mRNA transfection circumvents these risks and may be used for improving islet engraftment.
Mouse and human pancreatic islet cells were transfected with mRNA encoding the angiogenic growth factor vascular endothelial growth factor A (VEGF-A) before transplantation under the kidney capsule in mice.
At day 7 post transplantation, revascularisation of grafts transfected with Vegf-A (also known as Vegfa) mRNA was significantly higher compared with non-transfected or Gfp mRNA-transfected controls in mouse islet grafts (2.11- and 1.87-fold, respectively) (vessel area/graft area, mean ± SEM: 0.118 ± 0.01 [n = 3] in Vegf-A mRNA transfected group (VEGF) vs 0.056 ± 0.01 [n = 3] in no RNA [p < 0.05] vs 0.063 ± 0.02 [n = 4] in Gfp mRNA transfected group (GFP) [p < 0.05]); EndoC-bH3 grafts (2.85- and 2.48-fold. respectively) (0.085 ± 0.02 [n = 4] in VEGF vs 0.030 ± 0.004 [n = 4] in no RNA [p < 0.05] vs 0.034 ± 0.01 [n = 5] in GFP [p < 0.05]); and human islet grafts (3.17- and 3.80-fold, respectively) (0.048 ± 0.013 [n = 3] in VEGF vs 0.015 ± 0.0051 [n = 4] in no RNA [p < 0.01] vs 0.013 ± 0.0046 [n = 4] in GFP [p < 0.01]). At day 30 post transplantation, human islet grafts maintained a vascularisation benefit (1.70- and 1.82-fold, respectively) (0.049 ± 0.0042 [n = 8] in VEGF vs 0.029 ± 0.0052 [n = 5] in no RNA [p < 0.05] vs 0.027 ± 0.0056 [n = 4] in GFP [p < 0.05]) and a higher beta cell volume (1.64- and 2.26-fold, respectively) (0.0292 ± 0.0032 μl [n = 7] in VEGF vs 0.0178 ± 0.0021 μl [n = 5] in no RNA [p < 0.01] vs 0.0129 ± 0.0012 μl [n = 4] in GFP [p < 0.001]).
CONCLUSIONS/INTERPRETATION: Vegf-A mRNA transfection before transplantation provides a promising and safe strategy to improve engraftment of islets and other cell-based implants.
目的/假设：胰岛移植后的初始无血管期严重损害移植物功能和存活。通过基于病毒的血管生成触发物的递送来增强移植物再血管化以改善植入已被尝试，但与病毒载体相关的风险阻碍了临床转化。体外转录 mRNA 转染规避了这些风险，可用于改善胰岛移植。
在小鼠肾包膜下移植前，用编码血管生成生长因子血管内皮生长因子 A（VEGF-A）的 mRNA 转染小鼠和人胰岛细胞。
在移植后 7 天，与未转染或 GFP mRNA 转染对照相比，Vegf-A（也称为 Vegfa）mRNA 转染的胰岛移植物的再血管化明显更高（分别为 2.11 倍和 1.87 倍）（血管面积/移植物面积，平均值±SEM：VEGF 转染组为 0.118±0.01[n=3]，无 RNA 组为 0.056±0.01[n=3]，p<0.05；GFP mRNA 转染组为 0.063±0.02[n=4]，p<0.05）；EndoC-bH3 移植物（分别为 2.85 倍和 2.48 倍）（VEGF 组为 0.085±0.02[n=4]，无 RNA 组为 0.030±0.004[n=4]，p<0.05；GFP 组为 0.034±0.01[n=5]，p<0.05）；人胰岛移植物（分别为 3.17 倍和 3.80 倍）（VEGF 组为 0.048±0.013[n=3]，无 RNA 组为 0.015±0.0051[n=4]，p<0.01；GFP 组为 0.013±0.0046[n=4]，p<0.01）。在移植后 30 天，人胰岛移植物保持血管化优势（分别为 1.70 倍和 1.82 倍）（VEGF 组为 0.049±0.0042[n=8]，无 RNA 组为 0.029±0.0052[n=5]，p<0.05；GFP 组为 0.027±0.0056[n=4]，p<0.05）和更高的β细胞体积（分别为 1.64 倍和 2.26 倍）（VEGF 组为 0.0292±0.0032μl[n=7]，无 RNA 组为 0.0178±0.0021μl[n=5]，p<0.01；GFP 组为 0.0129±0.0012μl[n=4]，p<0.001）。
结论/解释：移植前 Vegf-A mRNA 转染为改善胰岛和其他基于细胞的植入物的植入提供了一种有前景且安全的策略。
