The ovine developmental model represents the standard in vivo model for studies involving maternofetal physiology, amniotic fluid (AF) research, and fetal cell therapy prior to human clinical use. Although being close to the human fetal anatomy, 2 separate extraembryonic fluid compartments remain during gestation, known as the amnion and the allantois. A clear distinction between AF versus allantoic fluid (AL) is therefore indispensable for correct scientific conclusions with regard to human translation. In the presented study, the biochemical composition of AF and AL was evaluated in ovine gravid uteri postmortem (n = 31) over the entire gestation. Four parameters, consisting of Na+, Cl–, Mg2+, and total protein, have been found to allow for specific discrimination of the 2 fetal fluids at all gestational phases and therefore as potential surrogate parameters for gestational age. In addition, volumetric changes of the developing fetus and the 2 fetal fluid cavities were analyzed by contrast-enhanced computed tomography (n = 12). AF showed a significant, linear volumetric increase over gestation, whereas AL volume maintained relatively static independent of gestational age. These results serve as a basis for future studies by providing surrogate markers enabling a reliable distinction of isolated fetal fluids and contained cells in the ovine developmental model over the entire gestation.

中文翻译：

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绵羊发育模型中与妊娠年龄相关的胎儿流体动力学：建立用于分化干细胞起源的替代标记

绵羊发育模型代表了涉及母胎生理学、羊水 (AF) 研究和人类临床使用前的胎儿细胞治疗的研究的标准体内模型。尽管接近人类胎儿的解剖结构，但在妊娠期间仍保留 2 个独立的胚胎外液隔室，称为羊膜和尿囊。因此，AF 与尿囊液 (AL) 之间的明确区别对于关于人工翻译的正确科学结论是必不可少的。在本研究中，AF 和 AL 的生化成分在整个妊娠期间在羊妊娠子宫死后 (n = 31) 中进行了评估。四个参数，由 Na+、Cl-、Mg2+ 和总蛋白组成，已发现允许在所有妊娠阶段对 2 种胎儿液体进行特定区分，因此可作为胎龄的潜在替代参数。此外，通过对比增强计算机断层扫描（n = 12）分析发育中的胎儿和 2 个胎儿液腔的体积变化。AF 在妊娠期间显示出显着的线性体积增加，而 AL 体积保持相对静态，与胎龄无关。这些结果通过提供替代标记物作为未来研究的基础，能够可靠地区分分离的胎儿体液和整个妊娠期绵羊发育模型中包含的细胞。通过对比增强计算机断层扫描 (n = 12) 分析发育中的胎儿和 2 个胎儿液腔的体积变化。AF 在妊娠期间显示出显着的线性体积增加，而 AL 体积保持相对静态，与胎龄无关。这些结果通过提供替代标记物作为未来研究的基础，能够可靠地区分分离的胎儿体液和整个妊娠期绵羊发育模型中包含的细胞。通过对比增强计算机断层扫描 (n = 12) 分析发育中的胎儿和 2 个胎儿液腔的体积变化。AF 在妊娠期间显示出显着的线性体积增加，而 AL 体积保持相对静态，与胎龄无关。这些结果通过提供替代标记物作为未来研究的基础，能够可靠地区分分离的胎儿体液和整个妊娠期绵羊发育模型中包含的细胞。