Mixed Pig-Human Chimerism in a Humanized Mouse Model

人源化小鼠模型中的混合猪-人嵌合现象

• 批准号: 8190127
• 负责人: Megan Sykes
• 金额: $ 45.96万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-15 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8190127
• 关键词: Allogenic; Animal Sources; Antibodies; Antibody Formation; Antigens; Automobile Driving; B-Lymphocytes; Bone Marrow Cells; CD34 gene; Cell physiology; Cells; Cellular Structures; Chimera organism; Chimerism; Complement; Dendritic Cells; Family suidae; Funding; Generations; Genetic; Hematopoiesis; Heterophile Antibodies; Human; Human Development; Immune; Immune response; Immune system; Immunization; Immunodeficient Mouse; Immunoglobulin Class Switching; Immunoglobulin G; Immunoglobulin-Secreting Cells; Immunosuppression; Infection; Interleukin-15; Lymphocyte; Modeling; Modification; Mus; Natural Killer Cells; Opportunistic Infections; Organ; Papio; Population; Process; Proteins; Rattus; Systems Analysis; T cell response; T-Lymphocyte; Testing; Tetanus Toxoid; Thymus Gland; Time; Toxic effect; Transgenic Organisms; Transplantation; Xenograft procedure; bone; clinical application; cytokine; cytotoxic; mouse model; nonhuman primate; pathogen; prevent; response; vector

Mixed xenogeneic chimerism is a promising approach to achieving tolerance across species barriers. This approach is being explored in nonhuman primates in Project 2. The studies in Project 3 will complement those in the nonhuman primate model by exploring the ability of porcine mixed xenogeneic chimerism to tolerize non-T cell components of the human immune system and analyzing the function of xenotolerant human T cells in detail. We have developed a humanized mouse model that allows generation of functional human T cells and B cells as well as human dendritic cells of several classes. These mice mount effective T cell responses and class-switched IgG responses following immunization and produce natural anti-pig xenoantibodies. We have also generated transgenic immunodeficient mice expressing porcine cytokines that promote porcine hematopoiesis from pig bone manow cells (BMCs). Using this model, we have demonstrated that the addition of porcine BMCs to the humanized mouse model results in central T cell tolerance induction specifically to the pig BMC donor, with preserved responsiveness to allogeneic and third party pig antigens. Our previous studies in the rat to mouse species combination have demonstrated that even low levels of mixed xenogeneic chimerism tolerize T cells centrally and tolerize natural killer (NK) cells and pre-existing natural antibody-producing B cells to the xenogeneic donor. In this proposal we will use this humanized mouse model to explore the ability of mixed porcine chimerism to tolerize human NK cells and B cells. We will also assess T cell function and the ability to clear opportunistic infections in pig-human mixed xenogeneic chimeras. We will: 1) Explore the ability of mixed xenogeneic chimerism to induce human NK cell tolerance in the pig-human species combination; 2) Explore the ability of mixed xenogeneic chimerism to induce human natural antibody-producing B cell tolerance in the pig-human species combination; and 3) Compare T cell immune responses in humanized mice with and without porcine mixed xenogeneic chimerism. These studies will assess T cell immune recognition in further detail and determine the ability to tolerize additional components of the human immune system that pose significant barriers to xenotransplantation. They have direct bearing on the mixed chimerism strategy being explored in the pig-->baboon model in Project 2 and will determine the potential utility of adding BMT to thymic transplantation in Project 1. The studies are also highly relevant to the non-Gal Nab studies in Projects 1 and 4.

混合的异构嵌合嵌合体是在物种障碍之间实现耐受性的一种有前途的方法。这 项目2中的非人类灵长类动物正在探索方法。项目3中的研究将补充 那些在非人类灵长类动物模型中，通过探索猪混合异构嵌合嵌合的能力 耐受人免疫系统的非T细胞成分并分析异种体的功能 人类T细胞详细。我们已经开发了人源化的小鼠模型，该模型允许产生功能 人类T细胞和B细胞以及几个类别的人类树突细胞。这些老鼠有效 免疫后T细胞反应和类切换的IgG反应，并产生天然抗PIG 异种抗体。我们还产生了表达猪细胞因子的转基因免疫缺陷小鼠 从猪骨骼的细胞（BMC）促进猪造血。使用此模型，我们有 证明在人源化小鼠模型中添加猪BMC会导致中央T细胞 对PIG BMC供体的耐受性诱导，对同种异体和第三 派对猪抗原。我们先前在大鼠对小鼠物种组合的研究表明， 即使是低水平的混合异种嵌合体可耐心地耐心地耐心，并耐受天然杀手（NK）细胞 以及对异构供体的预先存在的天然抗体生成B细胞。在此提案中，我们将使用 这种人源化的小鼠模型探索混合猪嵌合耐受人NK细胞的能力 和B细胞。我们还将评估T细胞功能以及清除猪曼的机会性感染的能力 混合异种嵌合体。我们将：1）探索混合异构嵌合诱导的能力 人类NK细胞的耐受性中的人类组合中的耐受性； 2）探索混合的能力 异构嵌合诱导人类诱导人类自然抗体的B细胞耐受性 物种组合； 3）将人性化小鼠的T细胞免疫反应与和 没有猪混合异构嵌合。这些研究将评估T细胞免疫识别 进一步的细节并确定能够耐受人类免疫系统的其他组成部分的能力 构成异种移植的明显障碍。他们直接与混合的嵌合策略有关 在项目2中的猪 - >狒狒模型中进行探索，并将确定添加BMT的潜在效用 在项目1中进行胸腺移植。该研究也与非GAL NAB研究高度相关 项目1和4。