探讨在既定免疫抑制策略干预下，基因编辑猪-恒河猴异种心脏移植术后免疫应答、心功能变化及组织结构重塑情况。

基于α-1，3-半乳糖基转移酶基因/β-1，4-N-乙酰半乳糖胺基转移酶2基因/人源CD46转基因/人源CD55转基因/人源血栓调节蛋白转基因五基因编辑供体猪，构建基因编辑猪-恒河猴异种心脏移植模型。免疫抑制方案分为诱导期和维持期，以抗CD154抗体和甲泼尼龙为基础；诱导期加用抗CD20抗体、抗胸腺细胞球蛋白和眼镜蛇毒因子，维持期联合吗替麦考酚酯并逐渐减量甲泼尼龙；发生急性排斥反应时予甲泼尼龙强化治疗。术后评估受体猴的生理指标、心功能、免疫细胞动态变化及组织学特征。

受体猴术后存活46 d，围手术期及术后早期一般状态相对稳定，未发生超急性或急性排斥反应。术后供、受体心脏均可维持有效收缩，受体猴自身心脏左心室射血分数始终维持在50%以上，供体猪心左心室射血分数整体较低，并伴左、右心室内膜进行性增厚，至实验终点均达基线水平的3倍左右。术后白细胞计数早期升高，红细胞和血小板计数未见持续性下降；氨基转移酶、总胆红素、凝血功能指标及肌钙蛋白水平呈阶段性波动。免疫组织化学结果示猪心肌CD68和IgG Fc段表达高于猴心肌。流式细胞术结果显示，术后第5天外周血CD3^＋CD19^－细胞比例升至74.9%，之后维持在76.2%~89.7%；CD3^－CD19^－细胞比例由手术当天的89.2%降至术后第1天的81.7%，之后维持在10.2%~25.0%，CD3^－CD19^＋细胞比例始终不超过0.1%；CD3^＋CD19^＋细胞比例于术后第7天升至3.4%，其余时间点未见明显升高。

在体液免疫被有效抑制的情况下，T细胞介导的细胞免疫应答是驱动移植物心脏结构改变和功能减退的主要机制。

To investigate the immune response, cardiac functional changes, and tissue remodeling following xenotransplantation of gene-edited pig hearts into rhesus macaques under current immunosuppressive strategies.

A pig-to-rhesus macaque heterotopic heart xenotransplantation model was established using a donor pig with five genes modifications (α-1, 3-galactosyltransferase/β-1, 4-N-acetylgalactosaminyltransferase 2/human CD46 transgene/human CD55 transgene/human thrombomodulin transgene). The immunosuppressive regimen comprised induction and maintenance phases and was based on anti-CD154 antibody and methylprednisolone. During the induction phase, anti-CD20 antibody, antithymocyte globulin, and cobra venom factor were additionally administered. During the maintenance phase, mycophenolate mofetil was added and methylprednisolone was gradually tapered. In the event of acute rejection, intensified methylprednisolone therapy was administered. Postoperative assessments included physiological parameters, cardiac function, immune cell dynamics, and histological features of the recipient monkey.

The recipient monkey survived for 46 days after transplantation. The recipient′s general condition remained relatively stable during the perioperative and early postoperative periods, with no hyperacute or acute rejection observed. Both the donor and recipient hearts maintained effective contractility after transplantation. The left ventricular ejection fraction of the recipient monkey′s native heart remained above 50% throughout the study, whereas that of the donor porcine heart was generally lower. Progressive thickening of the left and right ventricular endocardium was observed in the donor heart, reaching approximately threefold above baseline by the experimental endpoint. Leukocyte counts increased during the early postoperative period, whereas erythrocyte and platelet counts showed no sustained decline. Aminotransferase, total bilirubin, coagulation parameters, and troponin levels fluctuated over different postoperative phases. Immunohistochemistry showed higher CD68 and IgG Fc expression in porcine myocardium than in monkey myocardium. Flow cytometry showed that the proportion of peripheral blood CD3⁺ CD19^- cells increased to 74.9% on postoperative day 5, and thereafter remained between 76.2% and 89.7%. The proportion of CD3^-CD19^- cells decreased from 89.2% on the day of surgery to 81.7% on postoperative day 1, and thereafter remained between 10.2% and 25.0%. The proportion of CD3^-CD19⁺ cells remained below 0.1% throughout the observation period. The proportion of CD3⁺ CD19⁺ cells increased to 3.4% on postoperative day 7, with no marked increase observed at the other time points.

T cell-mediated cellular immune responses are the primary drivers of graft structural changes and functional deterioration under effective humoral immune suppression.