Somers Pamela, De Somer Filip, Cornelissen Maria, Bouchez Stefaan, Gasthuys Frank, Narine Kishan, Cox Eric, Van Nooten Guido
Heart Center, University Hospital Ghent, Ghent, Belgium.
J Heart Valve Dis. 2008 Nov;17(6):682-8.
One approach in tissue-engineering involves the implantation of decellularized, xenogenic scaffolds, with the expectation of repopulation in vivo. However, a major limitation of this method is the propensity to induce a strong immune host response. The study aim was to mitigate this immunogenicity by employing a crosslinking treatment with genipin.
Porcine matrices were prepared using a detergent-enzymatic treatment and fixed in 0.01% or 0.001% aqueous genipin. The mechanical properties of the matrices were monitored by tensile strength testing. The survival of chicken fibroblasts was used to determine cell-friendliness of the matrices. Non-fixed, decellularized biological scaffolds (n = 3) were implanted in a sheep model and compared to an equal number of genipin-fixed scaffolds (n = 6). Matrices implanted in the pulmonary position were explanted after six weeks and examined using light and transmission electron microscopy. The antibody reaction against porcine tissue in sheep serum was also determined.
Statistically significant differences were found between non-fixed leaflets, 0.001% genipin-and 0.6% glutaraldehyde (GA)-fixed leaflets for work to maximum load (non-fixed 0.00646 J; genipin-fixed 0.00509 J; GA-fixed 0.00543 J) and stiffness (non-fixed 9281 N/m; genipin-fixed 16214 N/m; GA-fixed 14401 N/m). Genipin-treated matrices were not cytotoxic. For all concentrations of genipin a high proportion of viable cells was present (79-100%). Low-dose GA (10 microg/ml) showed a distinct cytotoxicity (24.8% viability). At explant, an intense chronic inflammatory response was observed in non-fixed matrices, in contrast to genipin-fixed scaffolds. The sheep serum showed a marked decrease in IgG response in both 0.001% and 0.01% genipin-fixed matrices (IgG 30 and 20, respectively) when compared to non-fixed matrices (IgG 40).
Genipin crosslinking of the matrices attenuated, but did not eliminate, the inflammatory host reaction. Whether genipin treatment might extend the durability of xenogenic scaffolds remains to be investigated.
组织工程学中的一种方法是植入去细胞化的异种支架，期望其在体内重新填充细胞。然而，该方法的一个主要局限性是易于引发强烈的免疫宿主反应。本研究的目的是通过采用京尼平交联处理来减轻这种免疫原性。
使用去污剂 - 酶处理制备猪基质，并固定于0.01%或0.001%的京尼平水溶液中。通过拉伸强度测试监测基质的力学性能。用鸡成纤维细胞的存活率来确定基质的细胞友好性。将未固定的去细胞化生物支架（n = 3）植入绵羊模型中，并与相同数量的经京尼平固定的支架（n = 6）进行比较。植入肺部位置的基质在六周后取出，并用光学显微镜和透射电子显微镜检查。还测定了绵羊血清中针对猪组织的抗体反应。
在非固定小叶、0.001%京尼平固定小叶和0.6%戊二醛（GA）固定小叶之间，发现最大负荷功（非固定0.00646 J；京尼平固定0.00509 J；GA固定0.00543 J）和刚度（非固定9281 N/m；京尼平固定16214 N/m；GA固定14401 N/m）存在统计学显著差异。经京尼平处理的基质无细胞毒性。对于所有浓度的京尼平，均存在高比例的活细胞（79 - 100%）。低剂量GA（10微克/毫升）显示出明显的细胞毒性（存活率24.8%）。在取出时，与经京尼平固定的支架相比，在非固定基质中观察到强烈持久的炎症反应。与非固定基质（IgG 40）相比，0.001%和0.01%京尼平固定基质中的绵羊血清IgG反应均显著降低（分别为IgG 30和20）。
基质的京尼平交联减轻了，但并未消除，炎症宿主反应。京尼平处理是否可能延长异种支架的耐久性仍有待研究。
