Gene Medicine Research Group, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
Department of Biotechnology of Stem Cells and Organoids, Functional Unit for Research into Chronic Diseases, Instituto de Salud Carlos III, Madrid, Spain.
Stem Cell Res Ther. 2020 Oct 23;11(1):448. doi: 10.1186/s13287-020-01950-x.
Gene therapy is being investigated for a range of serious lung diseases, such as cystic fibrosis and emphysema. Recombinant adeno-associated virus (rAAV) is a well-established, safe, viral vector for gene delivery with multiple naturally occurring and artificial serotypes available displaying alternate cell, tissue, and species-specific tropisms. Efficient AAV serotypes for the transduction of the conducting airways have been identified for several species; however, efficient serotypes for human lung parenchyma have not yet been identified. Here, we screened the ability of multiple AAV serotypes to transduce lung bud organoids (LBOs)-a model of human lung parenchyma generated from human embryonic stem cells. Microinjection of LBOs allowed us to model transduction from the luminal surface, similar to dosing via vector inhalation. We identified the naturally occurring rAAV2 and rAAV6 serotypes, along with synthetic rAAV6 variants, as having tropism for the human lung parenchyma. Positive staining of LBOs for surfactant proteins B and C confirmed distal lung identity and suggested the suitability of these vectors for the transduction of alveolar type II cells. Our findings establish LBOs as a new model for pulmonary gene therapy and stress the relevance of LBOs as a viral infection model of the lung parenchyma as relevant in SARS-CoV-2 research.
基因治疗正在被研究用于一系列严重的肺部疾病，如囊性纤维化和肺气肿。重组腺相关病毒（rAAV）是一种成熟、安全的基因传递病毒载体，具有多种天然和人工血清型，可显示出不同的细胞、组织和物种特异性趋向性。已经确定了几种物种的高效 AAV 血清型用于传导气道的转导；然而，尚未确定用于人类肺实质的高效血清型。在这里，我们筛选了多种 AAV 血清型转导肺芽类器官（LBO）的能力-一种源自人类胚胎干细胞的人类肺实质模型。LBO 的微注射使我们能够模拟从腔表面进行转导，类似于通过载体吸入进行给药。我们确定了天然存在的 rAAV2 和 rAAV6 血清型以及合成的 rAAV6 变体，它们具有对人类肺实质的趋向性。表面活性剂蛋白 B 和 C 的 LBO 阳性染色证实了远端肺的身份，并表明这些载体适合肺泡 II 型细胞的转导。我们的发现确立了 LBO 作为一种新的肺部基因治疗模型，并强调了 LBO 作为肺部实质病毒感染模型的相关性，这在 SARS-CoV-2 研究中具有相关性。
