Gustafson Carl-Johan, Birgisson Agust, Junker Johan, Huss Fredrik, Salemark Lars, Johnson Hans, Kratz Gunnar
Department of Plastic and Reconstructive Surgery, Karolinska University Hospital, Stockholm, Sweden.
Burns. 2007 Sep;33(6):726-35. doi: 10.1016/j.burns.2006.10.382. Epub 2007 Apr 30.
Providing cutaneous wounds with sufficient epidermis to prevent infections and fluid loss is one of the most challenging tasks associated with surgical treatment of burns. Recently, application of cultured keratinocytes in this context has allowed this challenge to be met without several of the limitations connected with the use of split-thickness skin grafts. The continuous development of this novel approach has now revealed that transplantation of cultured autologous keratinocytes as single-cell suspensions exhibits several advantages over the use of cultured epidermal grafts. However, a number of methodological problems remain to be solved, primarily with regards to the complexity of culturing these cells; loss of viability and other negative effects during their preparation and transportation; the relatively long period of time required following transplantation to obtain a sufficiently protective epidermis. In the present investigation we attempted to eliminate these limitations by culturing the keratinocytes on macroporous gelatin spheres. Accordingly, the efficacies of normal human keratinocytes in single-cell suspension or growing on macroporous gelatin spheres, as well as of split-thickness skin grafts in healing wounds on athymic rats were compared. Human keratinocytes were found to adhere and proliferate efficiently both on the surface and within the pores of such spheres. Transplantation of such cells adherent to the spheres resulted in significantly more rapid formation of a stratified epidermis than did transplantation of single-cell suspensions or spheres alone. Twenty-three days after transplantation, the epidermis formed from the cells bound to the spheres was not as thick as the epidermis on wounds covered with split-thickness skin grafts, but significantly thicker than on wounds to which single-cell suspensions, spheres alone or no transplant at all was applied. Furthermore, fluorescence in situ hybridisation revealed that the transplanted keratinocytes, both those adherent to gelatin spheres and those in single-cell suspension, were components of the newly formed epidermis. These findings indicate that application of biodegradable macroporous spheres may prove to be of considerable value in designing cell-based therapies for the treatment of acute and persistent wounds.
为皮肤伤口提供足够的表皮以防止感染和体液流失是烧伤手术治疗中最具挑战性的任务之一。最近，在这种情况下应用培养的角质形成细胞使得这一挑战得以应对，而没有与使用中厚皮片相关的一些局限性。这种新方法的不断发展现已表明，作为单细胞悬液移植培养的自体角质形成细胞比使用培养的表皮移植物具有若干优势。然而，一些方法学问题仍有待解决，主要涉及培养这些细胞的复杂性；在其制备和运输过程中的活力丧失及其他负面影响；移植后获得足够保护性表皮所需的相对较长时间。在本研究中，我们试图通过在大孔明胶球上培养角质形成细胞来消除这些局限性。因此，比较了正常人角质形成细胞作为单细胞悬液或在大孔明胶球上生长时的功效，以及中厚皮片对无胸腺大鼠伤口愈合的功效。发现人角质形成细胞能在这种球体的表面和孔内有效黏附并增殖。移植黏附于球体的这种细胞导致分层表皮的形成比移植单细胞悬液或单独的球体明显更快。移植23天后，由黏附于球体的细胞形成的表皮不如覆盖中厚皮片的伤口上的表皮厚，但明显比应用单细胞悬液、单独的球体或根本不进行移植的伤口上的表皮厚。此外，荧光原位杂交显示，移植的角质形成细胞，无论是黏附于明胶球的还是单细胞悬液中的，都是新形成表皮的组成部分。这些发现表明，可生物降解大孔球体的应用在设计用于治疗急性和持续性伤口的基于细胞的疗法中可能具有相当大的价值。
