Tolerance Induction in a GAIT-KO Pig-to-Baboon Model Through Establishment ......

通过建立 GAIT-KO 猪狒狒模型的耐受性诱导......

• 批准号: 7549244
• 负责人: DAVID H SACHS
• 金额: $ 32.97万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7549244
• 关键词: Allogenic; Allografting; Animals; Antibodies; Antibody Formation; Antigens; Appearance; B-Lymphocytes; Blood specimen; Bone Marrow; Cell Surface Receptors; Cell Transplantation; Cell surface; Cells; Chimerism; Clinic; Clinical; Coagulation Process; Communicable Diseases; Complement; Condition; Data; Dose; Elements; Engraftment; Failure; Family suidae; Gait; Galactosyltransferases; Goals; Growth Factor; Hematopoietic; Hematopoietic stem cells; Human; Immune; Immune system; Immunity; Immunologics; Immunosuppression; Immunosuppressive Agents; In Vitro; Interleukin-3; Knock-out; Laboratories; Macaca fascicularis; Manuscripts; Mediating; Miniature Swine; Modality; Modeling; Modification; Natural Immunity; Natural Killer Cells; Organ; Organ Transplantation; Papio; Pathology; Pathway interactions; Peripheral; Phagocytosis; Pharmaceutical Preparations; Play; Polymerase Chain Reaction; Preparation; Prevention; Primates; Principal Investigator; Protocols documentation; Recombinants; Reporting; Rodent; Role; SCID Mice; Sampling Studies; Spleen; Standards of Weights and Measures; Stem cells; Sus scrofa; T-Cell Depletion; T-Lymphocyte; Testing; Therapeutic immunosuppression; Tissues; Transplantation; Transplantation Tolerance; Treatment Protocols; Xenograft procedure; absorption; conditioning; homologous recombination; human ITGA5 protein; irradiation; killings; knockout animal; macrophage; nonhuman primate; nuclear transfer; pre-clinical; prevent; programs; reconstitution; research study; response; success; thymus transplantation

Previous attempts to achieve mixed chimerism across the xenogeneic barrier of pig-to-primate have all failed, largely due to high levels of primate natural antibodies to the Gal antigen, expressed on the cell surface of all mature pig hematopoeitic cells. Thus, following mixed chimerism induction protocols in non-human primates, we have had evidence for long-term engraftment of pig hematopoietic stem cells (HSC), which do not appear to express Gal. However, despite antibody absorptions, inhibition of complement and various drug treatments, natural anti-Gal antibodies persisted and/or recurred, and appeared to play an important role in inhibiting the progeny of pig HSC from repopulating primate recipients. The recent availability of galactosyltransferase (Gal-T) knockout (GalT-KO) swine, derived from our most highly inbred line of miniature swine, has now made it possible to study pig-to-baboon xenotransplantation in the absence of effects of natural anti-Gal antibodies. The goal of this proposal is to utilize these new GalT-KO animals as hematopoietic cell donors for the establishment of mixed xenogeneic chimerism in the pig-to-baboon combination. Ourprevious studies and our preliminary data all suggest the feasibility of applying the mixed chimerism approach to induction of transplantation tolerance across this barrier, an approach already used successfully in this laboratory for allografts and concordant xenografts in rodents, pigs and cynomolgus monkeys. Specifically, we will: 1) Optimize the engraftment of HC from GalT-KO miniature swine in conditioned baboons; 2) Examine the role of selected innate immune and non-immune factors in promoting and/or resisting engraftment of GalT-KO HCin baboons; and 3) Test the role of GalT-KO pig HC engraftment in baboons enabling the induction of tolerance in recipients of subsequent organ xenografts. Aim 3, in particular, will apply the findings of Aims 1 and 2, as well as strategies developed in the other projects of this Program Project, to the mixed chimerism approach for inducing transplantation tolerance to organ xenografts in this preclinical, discordant species combination. In addition, the experiments planned will provide basic information on xenogeneic stem cell engrafment and on the immunologic pathways responsible for xenogeneic rejection and tolerance induction in primates. As such, these studies should have both theoretical and practical implications for the eventual application of xenotransplantation as a clinical modality.

以前试图通过猪到灵长类动物的异种屏障实现混合嵌合体的尝试， 失败，主要是由于高水平的灵长类动物天然抗体的Gal抗原，表达在细胞上 所有成熟猪造血细胞的表面。因此，按照混合嵌合体诱导方案， 在非人灵长类动物中，我们有证据表明猪造血干细胞可以长期植入 (HSC)，似乎不表达Gal.然而，尽管抗体抑制， 补体和各种药物治疗后，天然抗Gal抗体持续存在和/或复发， 似乎在抑制猪HSC子代在灵长类动物中的再增殖中起重要作用 受惠人士半乳糖基转移酶（Gal-T）敲除（GalT-KO）猪的最近可用性， 从我们最高度近亲繁殖的小型猪，现在已经有可能研究猪到狒狒 在不存在天然抗Gal抗体的作用下进行异种移植。这个目标 一项提议是利用这些新的GalT-KO动物作为造血细胞供体， 在猪-狒狒组合中建立混合异种嵌合体。我们的过去 研究和我们的初步数据都表明应用混合嵌合体方法的可行性， 为了跨越这一障碍诱导移植耐受，这种方法已经成功地用于 本实验室用于啮齿类动物、猪和食蟹猴的同种异体移植物和一致性异种移植物。 具体而言，我们将：1）优化来自GalT-KO小型猪的HC在小鼠中的植入。 条件狒狒; 2）检查选定的先天免疫和非免疫的作用 促进和/或抵抗GalT-KO HC在狒狒体内植入的因素;和3）测试 GalT-KO猪HC在狒狒中的植入能够诱导耐受性的作用， 随后的器官异种移植的接受者。具体而言，目标3将应用目标1的结论 和2，以及在本计划项目的其他项目中制定的战略，以混合 嵌合体方法诱导器官异种移植物的移植耐受性在这个临床前， 不协调的物种组合。此外，计划中的实验将提供以下方面的基本信息： 异种干细胞移植和异种干细胞移植的免疫途径 灵长类动物的排斥和耐受诱导。因此，这些研究应具有理论和 异种移植作为一种临床模式的最终应用的实际意义。