Branching morphogenesis of immortalized human bronchial epithelial cells in three-dimensional culture

Abstract

While mouse models have contributed in our understanding of lung development, repair and regeneration, inherent differences between the murine and human airways requires the development of new models using human airway epithelial cells. In this study, we describe a three-dimensional model system using human bronchial epithelial cells (HBECs) cultured on reconstituted basement membrane. HBECs form complex budding and branching structures on reconstituted basement membrane when co-cultured with human lung fetal fibroblasts. These structures are reminiscent of the branching epithelia during lung development. The HBECs also retain markers indicative of epithelial cell types from both the central and distal airways suggesting their multipotent potential. In addition, we illustrate how the model can be utilized to understand respiratory diseases such as lung cancer. The 3D novel cell culture system recapitulates stromal-epithelial interactions in vitro that can be utilized to understand important aspects of lung development and diseases.

A bioengineered niche promotes in vivo engraftment and maturation of pluripotent stem cell derived human lung organoids

“…These advances stem from our ability to culture primary human tissues and derive complex three-dimensional organ-like tissues, called organoids from human pluripotent stem cells (hPSCs) (Dedhia et al, 2016; Fatehullah et al, 2016; Johnson and Hockemeyer, 2015; Huch and Koo, 2015; Rookmaaker et al, 2015; Dye et al, 2016). Both tissue-derived and hPSC-derived human lung models have been developed and recapitulate some structural and cellular features of the human lung (Barkauskas et al, 2013; Rock et al, 2009; Gotoh et al., 2014; Konishi et al, 2016; Vaughan et al, 2006; Pageau et al, 2011; Fessart et al, 2013; Franzdóttir et al, 2010; Kaisani et al, 2014; Dye et al, 2015; Firth et al, 2014; Mou et al, 2016). For example, we recently described methods to direct differentiation of hPSCs in a stepwise process, which mimicked aspects of in vivo lung development, into three-dimensional human lung organoids (HLOs).…”

Organoids as a model system for studying human lung development and disease

“…For example, immortalized airway basal cells and HBECs can produce embryonic-like branching structures when co-cultured with fibroblasts or endothelial cells in 3D conditions [50,51]. These structures contain multipotent cells and structurally resemble the branching epithelia of lung development.…”

“…In mice, FGFs and transforming growth factors (TGFs) exert a strong effect on lung branching morphogenesis [67][68][69], but it remains to be determined whether these processes are fully conserved in humans. The branching structures produced from immortalized HBECs [50,51] mimic the developing lung in structure and contain cells with multipotent potential, providing a model that may serve as a starting point to begin addressing these questions.…”

“…Normal HBECs form organized networks of tubules that branch and bud when cultured in 3D conditions. Once HBECs are transformed they form tubular structures that fail to branch/bud, and instead develop an invasive phenotype indicative of malignant transformation [51]. Exploring the oncogenic transformation in lung organoid culture systems will allow the development of accessible models for studying tumorigenesis, and provide new pre-clinical models for evaluating treatments in a human-specific context.…”

“…HBEC-derived branching structures are used for modelling lung cancer progression [51]. hPSCs are differentiated into alveolar spheroids in vitro [63].…”