Amniotic extracelluar matrix microgels for attenuation of radiation-induced lung injury

Radiation-induced lung injury (RILI) is one of the major complications in patients exposed to accidental radiation and radiotherapy for thoracic malignancies. However, there is no reliable approach to effectively treat RILI. With favorable biological and physical characteristics, decellularized extracellular matrix (dECM) from amniotic membrane can not only act as a reactive oxygen species scavenger to attenuate the damage of oxidative stress, but also release bio-factors to polarize the macrophages from M1-like phenotype to M2-like phenotype, thus switching the microenvironment from pro-inflammation status to pro-healing status. Meanwhile, as a promising drug delivery system, microgels with a small size and high surface/volume ratio can not only be inhaled into lung tissues with a desired concentration, but also preserve the structural integrity and the functionalities of the contained therapeutics. Therefore, it will be a potent strategy to combine microgels and amniotic dECM for the treatment of RILI, in which the inhaled microgels show a high surface area to rapidly remove reactive oxygen species and release cargos to reduce the inflammation-mediated damage by modulating macrophage phenotypes. We hypothesize that amniotic dECM microgels will be a promising and effective biomaterial for the attenuation of RILI.