Silva Iran A N, Gvazava Nika, Bölükbas Deniz A, Stenlo Martin, Dong Jiao, Hyllen Snejana, Pierre Leif, Lindstedt Sandra, Wagner Darcy E
Lung Bioengineering and Regeneration, Department of Experimental Medical Sciences, Lund University, Lund, Sweden.
Wallenberg Center for Molecular Medicine, Lund University, Lund, Sweden.
Bio Protoc. 2022 Aug 20;12(16). doi: 10.21769/BioProtoc.4493.
Acute respiratory distress syndrome (ARDS) is a life-threatening, high mortality pulmonary condition characterized by acute lung injury (ALI) resulting in diffuse alveolar damage. Despite progress regarding the understanding of ARDS pathophysiology, there are presently no effective pharmacotherapies. Due to the complexity and multiorgan involvement typically associated with ARDS, animal models remain the most commonly used research tool for investigating potential new therapies. Experimental models of ALI/ARDS use different methods of injury to acutely induce lung damage in both small and large animals. These models have historically played an important role in the development of new clinical interventions, such as fluid therapy and the use of supportive mechanical ventilation (MV). However, failures in recent clinical trials have highlighted the potential inadequacy of small animal models due to major anatomical and physiological differences, as well as technical challenges associated with the use of clinical co-interventions [e.g., MV and extracorporeal membrane oxygenation (ECMO)]. Thus, there is a need for larger animal models of ALI/ARDS, to allow the incorporation of clinically relevant measurements and co-interventions, hopefully leading to improved rates of clinical translation. However, one of the main challenges in using large animal models of preclinical research is that fewer species-specific experimental tools and metrics are available for evaluating the extent of lung injury, as compared to rodent models. One of the most relevant indicators of ALI in all animal models is evidence of histological tissue damage, and while histological scoring systems exist for small animal models, these cannot frequently be readily applied to large animal models. Histological injury in these models differs due to the type and severity of the injury being modeled. Additionally, the incorporation of other clinical support devices such as MV and ECMO in large animal models can lead to further lung damage and appearance of features absent in the small animal models. Therefore, semi-quantitative histological scoring systems designed to evaluate tissue-level injury in large animal models of ALI/ARDS are needed. Here we describe a semi-quantitative scoring system to evaluate histological injury using a previously established porcine model of ALI via intratracheal and intravascular lipopolysaccharide (LPS) administration. Additionally, and owing to the higher number of samples generated from large animal models, we worked to implement a more sustainable and greener histopathological workflow throughout the entire process.
急性呼吸窘迫综合征（ARDS）是一种危及生命、死亡率高的肺部疾病，其特征为急性肺损伤（ALI）导致弥漫性肺泡损伤。尽管在ARDS病理生理学的理解方面取得了进展，但目前尚无有效的药物治疗方法。由于ARDS通常具有复杂性且涉及多器官，动物模型仍然是研究潜在新疗法最常用的研究工具。ALI/ARDS的实验模型使用不同的损伤方法在大小动物中急性诱导肺损伤。这些模型在新的临床干预措施（如液体疗法和支持性机械通气（MV）的使用）的开发中历来发挥着重要作用。然而，最近临床试验的失败凸显了由于主要的解剖学和生理学差异以及与临床联合干预措施（如MV和体外膜肺氧合（ECMO））使用相关的技术挑战，小动物模型可能存在的不足。因此，需要更大的ALI/ARDS动物模型，以便纳入临床相关的测量和联合干预措施，有望提高临床转化成功率。然而，在使用大型动物模型进行临床前研究时的主要挑战之一是，与啮齿动物模型相比，可用于评估肺损伤程度的物种特异性实验工具和指标较少。在所有动物模型中，ALI最相关的指标之一是组织学组织损伤的证据，虽然存在用于小动物模型的组织学评分系统，但这些系统通常不能轻易应用于大型动物模型。这些模型中的组织学损伤因所模拟损伤的类型和严重程度而异。此外，在大型动物模型中纳入其他临床支持设备（如MV和ECMO）可能会导致进一步的肺损伤以及出现小动物模型中不存在的特征。因此，需要设计用于评估ALI/ARDS大型动物模型中组织水平损伤的半定量组织学评分系统。在此，我们描述了一种半定量评分系统，该系统使用先前建立的通过气管内和血管内注射脂多糖（LPS）的猪ALI模型来评估组织学损伤。此外，由于大型动物模型产生的样本数量较多，我们努力在整个过程中实施更可持续、更环保的组织病理学工作流程。
