Mehta Vedanta, Abi-Nader Khalil N, Carr David, Wallace Jacqueline, Coutelle Charles, Waddington Simon N, Peebles Donald, David Anna L
Prenatal Cell and Gene Therapy Group, EGA Institute for Women's Health, University College London, London, UK.
Methods Mol Biol. 2012;891:291-328. doi: 10.1007/978-1-61779-873-3_14.
Safety is an absolute prerequisite for introducing any new therapy, and the need to monitor the consequences of administration of both vector and transgene to the fetus is particularly important. The unique features of fetal development that make it an attractive target for gene therapy, such as its immature immune system and rapidly dividing populations of stem cells, also mean that small perturbations in pregnancy can have significant short- and long-term consequences. Certain features of the viral vectors used, the product of the delivered gene, and sometimes the invasive techniques necessary to deliver the construct to the fetus in utero have the potential to do harm. An important goal of prenatal gene therapy research is to develop clinically relevant techniques that could be applied to cure or ameliorate human disease in utero on large animal models such as sheep or nonhuman primates. Equally important is the use of these models to monitor for potential adverse effects of such interventions. These large animal models provide good representation of individual patient-based investigations. However, analyses that require defined genetic backgrounds, high throughput, defined variability and statistical analyses, e.g. for initial studies on teratogenic and oncogenic effects, are best performed on larger groups of small animals, in particular mice. This chapter gives an overview of the potential adverse effects in relation to prenatal gene therapy and describes the techniques that can be used experimentally in a large animal model to monitor the potential adverse consequences of prenatal gene therapy, with relevance to clinical application. The sheep model is particularly useful to allow serial monitoring of fetal growth and well-being after delivery of prenatal gene therapy. It is also amenable to serially sampling using minimally invasive and clinically relevant techniques such as ultrasound-guided blood sampling. For more invasive long-term monitoring, we describe telemetric techniques to measure the haemodynamics of the mother or fetus, for example, that interferes minimally with normal animal behaviour. Implanted catheters can also be used for serial fetal blood sampling during gestation. Finally, we describe methods to monitor events around birth and long-term neonatal follow-up that are important when considering human translation of this therapy.
安全性是引入任何新疗法的绝对前提，监测载体和转基因对胎儿的给药后果尤为重要。胎儿发育的独特特征使其成为基因治疗的一个有吸引力的靶点，比如其不成熟的免疫系统和快速分裂的干细胞群体，但这也意味着孕期的微小干扰可能会产生重大的短期和长期后果。所用病毒载体的某些特性、所传递基因的产物，以及有时将构建体传递给子宫内胎儿所需的侵入性技术都有可能造成损害。产前基因治疗研究的一个重要目标是开发可应用于在绵羊或非人灵长类等大型动物模型中治疗或改善子宫内人类疾病的临床相关技术。同样重要的是利用这些模型监测此类干预的潜在不良反应。这些大型动物模型很好地代表了基于个体患者的研究。然而，对于需要明确遗传背景、高通量、明确变异性和统计分析的分析，例如对致畸和致癌作用的初步研究，最好在更大的小型动物群体，特别是小鼠中进行。本章概述了与产前基因治疗相关的潜在不良反应，并描述了可在大型动物模型中实验性使用的技术，以监测产前基因治疗的潜在不良后果，与临床应用相关。绵羊模型对于在产前基因治疗后连续监测胎儿生长和健康状况特别有用。它也适合使用超声引导下采血等微创且与临床相关的技术进行连续采样。对于更具侵入性的长期监测，我们描述了测量母体或胎儿血流动力学的遥测技术，例如，这种技术对正常动物行为的干扰最小。植入导管也可用于在妊娠期进行连续的胎儿采血。最后，我们描述了在考虑将这种疗法转化应用于人类时，监测出生前后事件和长期新生儿随访的方法。
