Developmental Biology and Regenerative Medicine Program, The Saban Research Institute at Children's Hospital Los Angeles, Los Angeles, California.
Department of Surgery, Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, California.
Am J Physiol Gastrointest Liver Physiol. 2020 Aug 1;319(2):G261-G279. doi: 10.1152/ajpgi.00387.2019. Epub 2020 Jun 29.
The small intestine has a remarkable ability to enhance its absorptive and digestive surface area through the formation of villi, a process known as villification. We sought to learn whether developing mouse and human tissue-engineered small intestine (TESI) followed known developmental biology routes to villification, such as Sonic hedgehog ()/Indian hedgehog () and bone morphogenetic protein 4 ()/forkhead box F1 () signaling to identify targets to enhance the development of TESI. After generating TESI from prenatal and postnatal stem cell sources, we evaluated the effect of cell source derivation on villification with a grading scheme to approximate developmental stage. χ analysis compared the prevalence of TESI grade from each stem cell source. RNAscope probes detected genes known to direct villification and the development of the crypt-villus axis in mouse and human development. These were compared in TESI derived from various pluripotent and progenitor cell donor cell types as well as native human fetal and postnatal tissues. Prenatal and pluripotent cell sources form mature villus and crypt-like structures more frequently than postnatal donor sources, and there are alternate routes to villus formation. Human TESI recapitulates epithelial to mesenchymal crosstalk of several genes identified in development, with fetal and pluripotent donor-derived TESI arriving at villus formation following described developmental patterns. However, postnatal TESI is much less likely to form complete villus-crypt patterns and demonstrates alternate / and / signaling patterns. Grading TESI and other cellular constructs may assist discoveries to support future human therapies. The small intestine can enhance its absorptive and digestive surface area through a process known as villification. Tissue-engineered small intestine achieves mature villification at varying levels of success between differing sources. We have developed a consistent grading schema of morphology and characterized it across multiple developmental pathways, allowing objective comparison between differing constructs and sources.
小肠通过形成绒毛来增强其吸收和消化表面积的能力，这个过程被称为绒毛化。我们试图了解发育中的小鼠和人类组织工程小肠（TESI）是否遵循已知的发育生物学途径进行绒毛化，例如 Sonic hedgehog（Shh）/Indian hedgehog（Ihh）和骨形态发生蛋白 4（BMP4）/forkhead box F1（FoxF1）信号传导，以确定增强 TESI 发育的靶点。在从产前和产后干细胞来源生成 TESI 后，我们评估了细胞来源对绒毛化的影响，采用分级方案来近似发育阶段。χ 分析比较了每个干细胞来源的 TESI 分级的流行率。RNAscope 探针检测了已知指导小鼠和人类发育中绒毛化和隐窝-绒毛轴发育的基因。在来自各种多能和祖细胞供体细胞类型以及天然人胎儿和产后组织的 TESI 中比较了这些基因。与产后供体来源相比，产前和多能细胞来源更频繁地形成成熟的绒毛和隐窝样结构，并且存在替代的绒毛形成途径。人类 TESI 重现了在发育中鉴定的几个基因的上皮-间充质串扰，胎儿和多能供体衍生的 TESI 遵循描述的发育模式到达绒毛形成。然而，产后 TESI 不太可能形成完整的绒毛-隐窝模式，并且表现出替代的 / 和 / 信号传导模式。对 TESI 和其他细胞构建体进行分级可能有助于支持未来人类治疗的发现。小肠可以通过称为绒毛化的过程增强其吸收和消化表面积。组织工程小肠在不同来源之间以不同的成功率达到成熟的绒毛化。我们已经开发了一种一致的形态学分级方案，并在多个发育途径中对其进行了特征描述，允许在不同的构建体和来源之间进行客观比较。
