Proteomic Discovery of Biomaterial Antigens

描述（由申请人提供）：组织工程假体，如使用异种生物材料作为支架的替代心脏瓣膜，提供了一种可以解决耐久性问题的活植入物的可能性。在这种应用中，异种生物材料经过“脱细胞”以去除细胞相关抗原，从而防止组织排斥。这种方法的假设是：1)重要的异种抗原仅与组织的细胞成分有关，2)组织学切片上细胞的消失等同于组织中抗原的完全去除。这些有缺陷的假设可能造成的不幸后果是最近报道的儿童协同移植物脱细胞非固定猪心脏瓣膜的灾难性失败。异种生物材料在戊二醛固定和组织工程生物假体中的应用可以通过更好地了解这些材料的免疫原性而得到加强。该方法的关键是更好地了解异种组织中抗原的数量和分布（例如细胞膜，细胞外基质）。因此，本建议的具体目的是：用二维凝胶电泳法提取和分离候选异种生物材料的细胞膜、细胞质和细胞外基质蛋白组分。2. 通过将分离的蛋白质暴露于自然发生的和获得的针对候选组织产生的抗体中来确定异种生物材料的抗原性。3. 用MALDI-TOF-TOF质谱法鉴定引起抗原反应的蛋白。本应用程序中描述的蛋白质组学方法提供了一种强大且特定的方法来筛选大量蛋白质，以获得跨物种的重要抗原性特性。这一信息将为异种组织工程组织的可行性和异种移植提供重要的见解。异种生物材料是来自动物的组织，可用于制造人类的替代组织（即组织工程）。该应用程序提供了有关生物材料免疫排斥的信息，在动物组织可用于组织工程之前，必须更好地了解这些信息。

DESCRIPTION (provided by applicant): Tissue-engineered prostheses such as replacement heart valves that utilize xenogeneic biomaterials as scaffold offer the possibility of a living implant that could resolve durability issues. In this application, xenogeneic biomaterials undergo "decellularization" to remove cell-associated antigens, thereby preventing tissue rejection. The assumptions of this approach are: 1) that important xenogeneic antigens are associated solely with the cellular component of the tissue, and 2) that disappearance of cells from histologic section equates to complete removal of antigens from the tissue. A likely and unfortunate consequence of these flawed assumptions was the recently reported catastrophic failure of Synergraft-decellularized non-fixed porcine heart valves in children. The application of xenogeneic biomaterials to fabrication of both glutaraldehyde-fixed and tissue-engineered bioprostheses could be enhanced by a better understanding of the immunogenicity of these materials. Critical to that approach is a better understanding of both the number and distribution (e.g. cell-membrane, extracellular matrix) of antigens within xenogeneic tissues. Thus, the specific aims of this proposal are: 1.To extract and separate by 2-D gel electrophoresis the cell membrane, cytoplasmic and extracellular matrix protein fractions of candidate xenogeneic biomaterials. 2. To determine antigenicity of xenogeneic biomaterials by exposing separated proteins to naturally-occurring and acquired antibodies generated against the candidate tissues. 3. To identify by MALDI-TOF-TOF mass spectrometry proteins that elicits an antigenic response. The proteomic approach described in this application offers a powerful and specific method for screening a large number of proteins for the critically important property of antigenicity across species. This information will provide important insight about the feasibility of xenogeneic tissue-engineered tissues and about xenotransplantation in general. Xenogeneic biomaterials are tissues from animals that could be used in the fabrication of replacement tissues for humans (i.e. tissue engineering). This application provides information about immune rejection of biomaterials that must be better understood before animal tissues can be used in tissue engineering.