Engineered hydrogel biomaterials facilitate lung progenitor cell differentiation from induced pluripotent stem cells

Lung progenitor (LP) cells identified by the expression of transcription factor NK2 homeobox 1 (NKX2.1) are essential for development of all lung epithelial cell types and hold tremendous potential for pulmonary research and translational regenerative medicine applications. Here we present engineered hydrogels as a promising alternative to the naturally derived materials that are often used to differentiate human induced pluripotent stem cells (iPSCs) into LP cells. Poly(ethylene glycol) norbornene (PEGNB) hydrogels with defined composition were used to systematically investigate the role of microenvironmental stiffness, cell origin, and splitting during the differentiation process. Results demonstrated that each of these factors impacted LP differentiation efficiency. Soft hydrogels replicating healthy lung stiffness (E = 4.00  0.25 kPa) produced the highest proportion of LP cells (54% by flow cytometry), stiff hydrogels (E = 18.83  2.24 kPa) resulted in 48% differentiation efficiency, and a thin coating of Matrigel on tissue culture (TC) plastic (E~3 GPa) resulted in the lowest proportion of LP cells (32%) at the end of the non-split differentiation protocol. Collectively these results showed that engineered hydrogels enable researchers to control parameters that impact cell differentiation and produce LP cells using well-defined microenvironments that may improve our ability to translate iPSC-derived LP cells into clinical applications.

通过转录因子NK2同源盒1（NKX2.1）表达的肺祖细胞（LP）对于所有肺上皮细胞类型的发育至关重要，并在肺科学研究以及转化再生医学应用领域展现出巨大的潜力。本研究旨在将工程化水凝胶作为一种有前景的替代品，用于区分人诱导多能干细胞（iPSCs）为LP细胞。本研究采用具有明确组成的聚乙二醇诺伯伦（PEGNB）水凝胶，系统性地探讨了微环境刚度、细胞来源以及分裂过程在分化中的作用。研究结果表明，这些因素均对LP分化效率产生影响。模拟健康肺组织刚度的软水凝胶（E = 4.00 ± 0.25 kPa）产生了最高的LP细胞比例（通过流式细胞术检测为54%），刚性水凝胶（E = 18.83 ± 2.24 kPa）导致48%的分化效率，而在非分裂分化方案结束时，组织培养塑料（TC）上的Matrigel薄膜（E~3 GPa）导致LP细胞比例最低（32%）。综上所述，这些结果表明，工程化水凝胶使研究人员能够控制影响细胞分化的参数，并利用定义明确的微环境来产生LP细胞，这可能会提高我们将iPSC来源的LP细胞转化为临床应用的能力。