XENOGENEIC THYMIC TRANSPLANTATION AS AN ADJUNCT TO TREATMENT OF AIDS

异种胸腺移植作为艾滋病治疗的辅助手段

• 批准号: 6591306
• 负责人: M ROSENZWEIG
• 金额: $ 11.11万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-05-01 至 2003-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6591306
• 关键词: AIDS; animal tissue; communicable diseases; immunology; inflammation; lymphatic system; transplantation; virus

The goal of this project is to determine the feasability of xenogeneic pig thymus to engraft in an SIV infected macaque, and to determine if this has any impact on T cell reconstitution The initial aim was to establish baseline assays to determine the degree of immunosupression as a result of SIV We have conducted comprehensive analysis to determine the optimal in vitro conditions to determine both alloantigen and xenoantigen responses in macaques Our data demonstrate poor to absent xeno and allo- responses in macaques with advanced SIV disease, as well as 1-2 log reduction in the proliferation response to lectin Based on the poor in vitro proliferative responses we wished to examine whether pig thymic tissue might engraft in SIV-infected macaques without any conditioning We therefore performed transplants of pig thymic tissue in 2 SIV-infected macaques with advanced disease (CD4<200 mm3) Biopsy of the transplant site at 30 days revealed lymphoid aggrega tes of rhesus T cells in both animals, with only minimal inflammatory changes outside the lymphoid aggregates No evidence for engraftment of pig thymic tissue was observed (negative results for pig cytokeratin, MHC class I, MHC class II, and CD2) These results suggest that even SIV-infected animals with advanced disease are able to mount sufficient immune responses to reject swine thymus Due to our inability to achieve engraftment of pig thymus in SIV infected macaques in the absence of conditioning (see below), we altered our experimental design to include a conditioning protocol, namely cyclophosphamide anti-thymocyte globulin (ATG) and cyclosporine In the first animal examined, we achieved 99% depletion of peripheral T cells (CD3+) following ATG treatment, but the CD3+ count rapidly returned to baseline within 3 days The second animal received 3 additional days of ATG, but we observed poor T cell depletion only (90%) depletion after 6 days of ATG Both animals received pig thymus in both the omentum and quadriceps Antiretroviral therapy as well as PCP prophylaxis was continued Biopsies of the quadriceps muscle transplant sites at 1 and 3 months demonstrated profound infiltration of rhesus CD3+CD8+ T cells into the area, with no evidence for engraftment as detected by immunohistochemistry for cytokeratin as well as pig-specific antigens We concluded that we had a low level engraftment, but no clear functional thymus was detected A clear problem in data interpretation is that the animals both had detectable thymus in the mediastinum at autopsy, so the rebound of naive T cells cannot be used as an indicator of engraftment and function, this will be addressed by performing thymectomy prior to SIV-infection in subsequent animals

该项目的目的是确定 异构猪百里香在SIV感染的猕猴中植入，然后 确定这是否对T细胞重建有任何影响 目的是建立基线测定以确定 由于SIV的结果，我们进行了全面的选择 分析以确定最佳体外条件以确定 猕猴中的同种抗原和异种抗原响应我们的数据 表现出较差的XENO和猕猴中的反应 晚期SIV疾病，以及减少1-2对数 基于体外较差的凝集素的增殖反应 我们希望检查猪胸腺组织的增殖反应 可能会在SIV感染的猕猴中食用，而无需任何条件 因此，在2 SIV感染的2个SIV感染中对猪胸腺组织进行了移植 患有晚期疾病的猕猴（CD4 <200 mm3）移植活检 30天的部位揭示了恒河类T细胞的淋巴聚集 两种动物，只有最小的炎症变化 淋巴骨料没有证据表明猪胸腺组织的植入 观察到（猪细胞角蛋白，MHC I类，MHC负面结果 II类和CD2）这些结果表明，即使是SIV感染了 患有晚期疾病的动物能够实现足够的免疫力 由于我们无法实现而拒绝猪胸腺的反应 在没有的情况下，在SIV感染的猕猴中植入了猪胸腺 调理（见下文），我们将实验设计更改为 包括调节方案，即环磷酰胺 第一动物中的​​抗胸腺细胞球蛋白（ATG）和环孢菌素 经过检查，我们达到了99％的外围T细胞耗尽（CD3+） 遵循ATG处理，但CD3+计数迅速恢复到 基线在3天内，第二只动物又收到了3天 ATG，但我们观察到T细胞仅在 6天的ATG两只动物在omentum和 股四头肌抗逆转录病毒疗法以及PCP预防是 股四头肌肌肉移植部位的持续活检，1 3个月显示恒河所CD3+ CD8+ T细胞的深刻渗透 进入该地区，没有证据表明植入 细胞角蛋白和猪特异性抗原的免疫组织化学 我们得出的结论是，我们有一个低水平的植入，但尚无清楚 在数据解释中检测到功能性胸腺明显问题 是动物俩在纵隔中都有可检测到的胸腺 尸检，因此天真T细胞的反弹不能用作 植入和功能的指标，这将通过 在随后的动物中进行SIV感染之前进行胸腺切除术