Department of Obstetrics and Gynecology, University of Yamanashi, 1110 Simokato, Chuo, Yamanashi 409-3898, Japan.
J Reprod Immunol. 2010 Mar;84(2):117-23. doi: 10.1016/j.jri.2009.11.006. Epub 2010 Jan 29.
Fetus-derived cells are present in the blood and tissues of the maternal body over a long period of time, even after delivery, resulting in fetal cell microchimerism. The exact process by which fetal cells cross the placental barrier to enter the maternal circulation is unclear. The objective of this paper was to determine the time during pregnancy that fetal cells with multilineage potential migrate to the maternal organs. Wild type female mice were crossbred with male transgenic mice, expressing enhanced green fluorescent protein (EGFP). Total hysterectomies were performed at different time points of pregnancy. On day 60 after surgery, mice were injected with either streptozotocin (STZ) to induce insulin-dependent diabetes mellitus, or vehicle. Detection and quantification of fetal cells were then undertaken in a variety of maternal organs via fluorescent microscopy and quantitative PCR amplification of the gfp transgene. In vehicle control mice, fetal cells were detected only in the maternal bone marrow. However on day 30 after STZ injection, fetal cells were detected not only in bone marrow but also in the maternal pancreas, liver and kidney. Histological analysis showed differentiated fetal cells within the pancreatic acinar cells, hepatocytes and tubular epithelial cells. Their morphological appearance was indistinguishable from their maternal counterparts, and their frequency in these organs was constant, regardless of the timing of hysterectomy. These results indicate that most fetal cells with multilineage potential in maternal tissues migrate to the maternal body early after implantation, and thereafter sustain their population over the long term after delivery.
胎儿来源的细胞在母体的血液和组织中存在很长一段时间，甚至在分娩后，导致胎儿细胞微嵌合体。胎儿细胞穿过胎盘屏障进入母体循环的确切过程尚不清楚。本文的目的是确定具有多能性的胎儿细胞迁移到母体器官的妊娠时间。将表达增强型绿色荧光蛋白（EGFP）的雄性转基因小鼠与野生型雌性小鼠杂交。在妊娠的不同时间点进行全子宫切除术。手术后第 60 天，给小鼠注射链脲佐菌素（STZ）诱导胰岛素依赖性糖尿病，或注射载体。然后通过荧光显微镜和 GFP 转基因的定量 PCR 扩增，在各种母体器官中检测和定量胎儿细胞。在载体对照小鼠中，仅在母体骨髓中检测到胎儿细胞。然而，在 STZ 注射后第 30 天，不仅在骨髓中，而且在母体胰腺、肝脏和肾脏中也检测到了胎儿细胞。组织学分析显示在胰腺腺泡细胞、肝细胞和管状上皮细胞中有分化的胎儿细胞。它们的形态外观与其母体细胞无法区分，并且它们在这些器官中的频率是恒定的，与子宫切除术的时间无关。这些结果表明，母体组织中具有多能性的大多数胎儿细胞在植入后早期迁移到母体，并且在分娩后很长一段时间内维持其种群。
