Women with antiphospholipid antibodies (aPL) have increased risks of pregnancy complications, including a ten-fold increased risk of preeclampsia, which is potentially triggered by the release of placental toxins. Previously, aPL were shown to enter the outer layer of the placenta, the syncytiotrophoblast, associate with mitochondria, and alter mitochondrial function. We hypothesised that aPL may also increase mitochondrial reactive oxygen species (ROS) production, leading to cellular dysfunction and release of toxins. First trimester placental explants were incubated with monoclonal aPL, ID2 and IIC5 (25, 50, and 100 μg/mL), for 3 h at 37 °C and ROS production followed using CellROX Deep Red. In addition, the candidate treatment compounds chloroquine, melatonin, and Mito-Q were tested at therapeutic concentrations for their ability to prevent ROS production. Mitochondria isolated from term placentae were incubated with fluorescently-labelled ID2, IIC5, or control IgG antibodies (2.5, 5, 10, or 20 μg/mL) for 30 min, and mitochondria with bound antibodies were quantified using flow cytometry. In addition, respirometry coupled with fluorimetry was used to interrogate explant mitochondrial respiration and ROS production following incubation with 25, 50, or 100 μg/mL ID2, IIC5, or control IgG for 3 h at 37 °C. ID2 increased explant ROS production in a manner that was completely prevented by the endocytosis inhibitor chloroquine, and partially prevented by the antioxidants melatonin and Mito-Q. Both ID2 and IIC5 displayed a greater ability to bind isolated mitochondria than control antibodies, and increased ROS production attributable to the mitochondrial enzyme glycerol 3-phosphate dehydrogenase (mGPDH). Our evidence supports the hypothesis that aPL interact with syncytiotrophoblast mitochondria, likely via the binding of cardiolipin and β₂ glycoprotein I in mitochondrial membranes, and induce ROS production which contributes to overall oxidative stress and placental dysfunction.

具有抗磷脂抗体 (aPL) 的女性患妊娠并发症的风险增加，包括先兆子痫的风险增加 10 倍，这可能是由胎盘毒素的释放引发的。以前，aPL 被证明进入胎盘的外层，即合体滋养层，与线粒体相关联，并改变线粒体功能。我们假设 aPL 也可能增加线粒体活性氧 (ROS) 的产生，导致细胞功能障碍和毒素释放。孕早期胎盘外植体与单克隆 aPL、ID2 和 IIC5（25、50 和 100 μg/mL）一起在 37°C 下孵育 3 小时，然后使用 CellROX Deep Red 产生 ROS。此外，候选治疗化合物氯喹、褪黑激素、和 Mito-Q 在治疗浓度下测试了它们防止 ROS 产生的能力。从足月胎盘中分离的线粒体与荧光标记的 ID2、IIC5 或对照 IgG 抗体（2.5、5、10 或 20 μg/mL）孵育 30 分钟，并使用流式细胞术对结合抗体的线粒体进行定量。此外，在与 25、50 或 100 μg/mL ID2、IIC5 或对照 IgG 在 37°C 下孵育 3 小时后，使用呼吸测定法和荧光测定法来询问外植体线粒体呼吸和 ROS 的产生。ID2 以一种被内吞抑制剂氯喹完全阻止的方式增加外植体 ROS 的产生，并且部分被抗氧化剂褪黑激素和 Mito-Q 阻止。ID2 和 IIC5 都表现出比对照抗体更强的结合分离线粒体的能力，线粒体酶甘油 3-磷酸脱氢酶 (mGPDH) 产生的 ROS 增加。我们的证据支持 aPL 与合体滋养层线粒体相互作用的假设，可能是通过心磷脂和 β 的结合₂糖蛋白 I 在线粒体膜中，并诱导 ROS 产生，这有助于整体氧化应激和胎盘功能障碍。