Markowicz Marta, Koellensperger Eva, Neuss Sabine, Koenigschulte Sarah, Bindler Christine, Pallua Norbert
Department of Plastic Surgery, Hand and Burn Surgery, RWTH Aachen University, Pauwelsstrasse 30, 52057 Aachen, Germany.
Cell Transplant. 2006;15(8-9):723-32. doi: 10.3727/000000006783464408.
In the correction of functional and aesthetic impairments, loss of soft connective tissue creates the need for adequate implant material. The reconstruction of defects resulting from radical excisions, trauma, or hereditary diseases has seen the use of combined grafts and flaps. With the aim of minimizing donor site morbidity, new methods have been evaluated. Because of a low rate of vascularization, with artificial dermal templates the take has only been poor. As shown in previous studies, improved angiogenetic potency and epidermal formation has been obtained in modified, cell-seeded collagen matrices. We have now investigated the suitability of adult bone marrow mesenchymal stem cells (hMSC) for soft tissue engineering. In this study, hMSC were isolated and expanded. Cells (10(6)) were seeded onto EDC cross-linked collagen sponges and implanted in 30 immunodeficient mice. Collagen sponges without cells were used as controls. The grafts were evaluated after 2 and 6 weeks. After explantation, macroscopic appearance, weights, and histology (scaffold degradation, cellularity, and invasion depth of the seeded cells) were all assessed. After 2 and 6 weeks in vivo, new vessels were found macroscopically on all cell-seeded collagen grafts. The control grafts appeared to be degraded with a lower rate of vessel ingrowth. In the experimental group, weight gain was significant after 2 and 6 weeks in vivo compared to the same grafts after 72 h in vitro, while weight increased only slightly in the control group. Histologically, populated scaffolds showed a high density of vascularization under a capsule. The control sponges showed single capillaries and a thicker capsule. Compared to the controls, cellularity (cells/field) was greater in cell-containing collagen grafts after 2 and 6 weeks. The results obtained demonstrate that in vitro cultured human mesenchymal stem cells seeded on modified collagen sponges may be able to act as a replacement for soft tissue.
在功能和美学障碍的矫正中，软组织的缺失产生了对合适植入材料的需求。根治性切除、创伤或遗传性疾病导致的缺损重建已采用联合移植和皮瓣。为了将供区发病率降至最低，人们对新方法进行了评估。由于血管化率低，人工真皮模板的成活率一直很低。如先前研究所示，在改良的、接种细胞的胶原基质中，血管生成能力和表皮形成得到了改善。我们现在研究了成人骨髓间充质干细胞（hMSC）在软组织工程中的适用性。在本研究中，分离并扩增了hMSC。将细胞（10⁶）接种到EDC交联的胶原海绵上，并植入30只免疫缺陷小鼠体内。无细胞的胶原海绵用作对照。在2周和6周后对移植物进行评估。取出后，评估宏观外观、重量和组织学（支架降解、细胞密度和接种细胞的浸润深度）。在体内2周和6周后，在所有接种细胞的胶原移植物上肉眼可见新血管。对照移植物似乎降解较慢，血管长入率较低。在实验组中，与体外培养72小时后的相同移植物相比，体内2周和6周后重量显著增加，而对照组重量仅略有增加。组织学上，植入细胞的支架在包膜下显示出高密度的血管化。对照海绵显示单个毛细血管和较厚的包膜。与对照组相比，含细胞的胶原移植物在2周和6周后的细胞密度（细胞/视野）更高。所得结果表明，接种在改良胶原海绵上的体外培养人骨髓间充质干细胞可能能够替代软组织。
