Tissue-Engineered Lung: AnIn VivoandIn VitroComparison of Polyglycolic Acid and Pluronic F-127 Hydrogel/Somatic Lung Progenitor Cell Constructs to Support Tissue Growth

Abstract

In this study, we describe the isolation and characterization of a population of adult-derived or somatic lung progenitor cells (SLPC) from adult mammalian lung tissue and the promotion of alveolar tissue growth by these cells (both in vitro and in vivo) after seeding onto synthetic polymer scaffolds. After extended in vitro culture, differentiating cells expressed Clara cell 10kDa protein, surfactant protein-C, and cytokeratin but did not form organized structures. When cells were combined with synthetic scaffolds, polyglycolic acid (PGA) or Pluronic F-127 (PF-127), and maintained in vitro or implanted in vivo, they expressed lung-specific markers for Clara cells, pneumocytes, and respiratory epithelium and organized into identifiable pulmonary structures (including those similar to alveoli and terminal bronchi), with evidence of smooth muscle development. Although PGA has been shown to be an excellent polymer for culture of specific cell types in vitro, in vivo culture in an immunocompetent host induced a foreign body response that altered the integrity of the developing lung tissue. Use of PF-127/cell constructs resulted in the development of tissue with less inflammatory reaction. These data suggest that the therapeutic use of engineered tissues requires both the use of specific cell phenotypes, as well as the careful selection of synthetic polymers, to facilitate the assembly of functional tissue.

Thermoresponsive hydrogels in biomedical applications

“…This polymer has been found to have a rapid gelation at 37°C (after one-minute incubation, 30% solution in cell culture medium) [59]. F127 was evaluated as a scaffold for lung tissue engineering, showing promising results on tissue growth with low inflammatory response [60]. Weinand and colleagues [59] tested a β-tricalcium phosphate (β-TCP) scaffold, using a F127 hydrogel to facilitate cell delivery and distribution for an in vitro study aiming at bone regeneration.…”

Tooth Organ Engineering: Biological Constraints Specifying Experimental Approaches

“…For this reason, they have been widely used for tissue engineering. The possibility to re-create a specific histological organization has been investigated, in the case of lung tissue engineering by growing pluripotent cells seeded onto synthetic polymers, showing that identifiable pulmonary structures could develop (Cortiella et al, 2006). Although PGA is satisfactory to grow cells in vitro, this polymer can induce inflammatory reactions after implantation in immunocompetent hosts (Ceonzo et al, 2006;Cortiella et al, 2006).…”

“…The possibility to re-create a specific histological organization has been investigated, in the case of lung tissue engineering by growing pluripotent cells seeded onto synthetic polymers, showing that identifiable pulmonary structures could develop (Cortiella et al, 2006). Although PGA is satisfactory to grow cells in vitro, this polymer can induce inflammatory reactions after implantation in immunocompetent hosts (Ceonzo et al, 2006;Cortiella et al, 2006). Different groups have used PGA for tooth engineering (Duailibi et al, 2004(Duailibi et al, , 2008Iwatsuki et al, 2006;Ohara et al, 2010), but the risk of inflammation was only discussed by Duailibi et al (2008).…”

Coming to terms with tissue engineering and regenerative medicine in the lung

“…Synthetic polymers such as polyglycolic acid (175), polylactic-coglycolic acid (PLGA) (122), and pluronic F-127 are also considered of substantial interest in the context of lung scaffolds (35). An obvious advantage of using such synthetic material is the ability to tailor their chemical and biological properties with additional manipulation to achieve desirable mechanical properties.…”