怀孕期间会发生多种复杂的生物过程，包括胎儿细胞迁移到母体循环以及随后植入母体组织并形成微嵌合体。胎儿微嵌合体已在多种组织中被发现；然而，它们的功能作用在很大程度上仍然未知。不同的报告表明这些细胞有助于组织修复和调节免疫反应，但它们也与先兆子痫和肿瘤形成有关。在母体心脏中，心肌梗塞后，胎儿来源的细胞可以形成不同的细胞谱系。然而，这些细胞的功能作用及其对心脏功能和修复的影响尚不清楚。在这项工作中，我们发现胎儿起源的微嵌合体存在于母体循环和心脏移植物中。为了确定它们的功能作用，将 WT 雌性小鼠与表达白喉毒素 (DT) 受体的雄性小鼠杂交。母亲接受 DT 治疗以消除微嵌合体，并研究对心肌梗塞的反应。我们发现，与未经治疗的小鼠相比，微嵌合体的去除改善了产后和梗死后模型雌性的心脏收缩，而未治疗的小鼠中DT给药没有显着效果。这些结果表明，微嵌合体在母亲心肌梗塞后发挥着有害作用。版权所有 © 2024 Llorente、López-Olañeta、Blázquez-López、Vázquez-Ogando、Martínez-García、Vaquero、Carmona、Desco、Lara-Pezzi 和 Gómez-Gaviro 。

Multiple complex biological processes take place during pregnancy, including the migration of fetal cells to maternal circulation and their subsequent engraftment in maternal tissues, where they form microchimerisms. Fetal microchimerisms have been identified in several tissues; nevertheless, their functional role remains largely unknown. Different reports suggest these cells contribute to tissue repair and modulate the immune response, but they have also been associated with pre-eclampsia and tumor formation. In the maternal heart, cells of fetal origin can contribute to different cell lineages after myocardial infarction. However, the functional role of these cells and their effect on cardiac function and repair are unknown. In this work, we found that microchimerisms of fetal origin are present in the maternal circulation and graft in the heart. To determine their functional role, WT female mice were crossed with male mice expressing the diphtheria toxin (DT) receptor. Mothers were treated with DT to eliminate microchimerisms and the response to myocardial infarction was investigated. We found that removal of microchimerisms improved cardiac contraction in postpartum and post-infarction model females compared to untreated mice, where DT administration had no significant effects. These results suggest that microchimerisms play a detrimental role in the mother following myocardial infarction.Copyright © 2024 Llorente, López-Olañeta, Blázquez-López, Vázquez-Ogando, Martínez-García, Vaquero, Carmona, Desco, Lara-Pezzi and Gómez-Gaviro.