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......

基本信息

批准号：
7790537
负责人：
DAVID H SACHS
金额：
$ 37.73万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2000
资助国家：
美国
起止时间：
2000-09-15 至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/7790537
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 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 Preparation Prevention Primates Principal Investigator Protocols documentation Recombinants Reporting Rodent Role SCID Mice Sampling Studies Spleen Stem cells T-Cell Depletion T-Lymphocyte Testing Tissues Transplantation Transplantation Tolerance Treatment Protocols Xenograft procedure absorption conditioning homologous recombination human ITGA5 protein irradiation killings knockout animal macrophage meetings nonhuman primate nuclear transfer pre-clinical prevent programs reconstitution research study response success thymus transplantation

项目摘要

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.

之前跨越猪与灵长类动物异种屏障实现混合嵌合的尝试均取得了成功。失败，主要是由于细胞上表达的针对 Gal 抗原的灵长类动物天然抗体水平较高所有成熟猪造血细胞的表面。因此，遵循混合嵌合诱导方案在非人类灵长类动物中，我们有猪造血干细胞长期植入的证据（HSC），它似乎不表达 Gal。然而，尽管抗体被吸收，但抑制补体和各种药物治疗、天然抗 Gal 抗体持续存在和/或复发，以及似乎在抑制猪 HSC 后代繁殖灵长类动物中发挥重要作用收件人。最近推出的半乳糖基转移酶 (Gal-T) 敲除 (GalT-KO) 猪，源自来自我们最高度近交系的小型猪，现在使研究猪与狒狒成为可能在没有天然抗 Gal 抗体作用的情况下进行异种移植。此举的目标建议利用这些新的 GalT-KO 动物作为造血细胞供体在猪与狒狒组合中建立混合异种嵌合体。我们的上一个研究和我们的初步数据都表明应用混合嵌合方法的可行性诱导跨过这一屏障的移植耐受性，这种方法已成功用于该实验室用于啮齿动物、猪和食蟹猴的同种异体移植和一致异种移植。具体来说，我们将： 1) 优化 GalT-KO 小型猪的 HC 植入条件反射狒狒； 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 HCin 狒狒植入的因素； 3) 测试 GalT-KO猪HC植入在狒狒中的作用，能够诱导耐受性随后器官异种移植的接受者。特别是目标 3 将应用目标 1 的研究结果 2，以及本计划项目的其他项目中制定的策略，以混合在此临床前，诱导对器官异种移植物的移植耐受的嵌合方法，不和谐的物种组合。此外，计划的实验将提供以下方面的基本信息：异种干细胞植入和负责异种的免疫途径灵长类动物的排斥和耐受诱导。因此，这些研究应该具有理论和对异种移植作为临床方式的最终应用的实际影响。