Integral tissue regeneration is a major unmet medical need.The recent pivotal work of the coordinator provides a unique clinical situation of induced de novo generation of trachea and bronchus. Local immunoregulatory responses involving regulatory T (treg) cells responsive to IL-33 are important to promote tissue repair in animals. We aim at determining the optimal combination of immune cells and of specific molecules that promote tissue regeneration and repair from tissues with clinically occurring regeneration or in control trachea. Tissue cells and immune cells will be cocultured in invtiro sytems. We will verify in mice whether some combinations of molecules and specific cells such as Treg cells, can promote tissue repair in those mice.