Sulfur Mustard (SM) remains a significant threat to civilian and military populations. Skin exposure to SM induces erythema, followed by edema and large blisters in the affected area, with prolonged healing times. The sequence and manner of cell death and detachment in this injury are still unresolved, in part due to incomplete in vitro and preclinical models. Since the goal of an ex vivo 3D skin model is to replicate the authentic anatomy and physiology of native skin, there is an immense need to develop bioengineered skin with multiple cell types and appropriate physiological potential. Assessment of bioprinted skin as an ex vivo organoid (organ tissue equivalent) has demonstrated that it maintains its layered structure for over 2 months in vitro. Assessment of skin organoids by RNA and protein analysis demonstrate a physiological response similar to those seen in normal human skin. These encouraging results suggest that this skin construct is recapitulating the human organ and we propose to use the funds available through this supplement to further expand the bioprinted human skin into a model of chemical burn injuries. We will use bioprinted skin to model exposure to the known chemical vesicant sulfur mustard (SM), with the ultimate goal of showing the full utility of the bioprinted skin in elucidating biochemical and pathophysiological pathways in an effort to discover biomarkers and medical countermeasures. Based on the data we have generated to date, our central hypothesis is that ex vivo bioprinted skin will model clinical pathological effects of exposure to the chemical vesicant sulfur mustard. The overall goal of this supplemental proposal is to generate proof of principal data showing that the bioprinted skin will respond to the chemical insult in a way that is consistent with the known effects of SM. Our study will validate the dose and time of exposure for modeling the human response to SM in vitro, and will include histological, qRT-PCR, and ELIZA analysis. These studies will focus on demonstrating that the bioprinted skin behaves in a way that is consistent with Specific Aim 1 will characterize the pathological consequences of sulfur mustard exposure.
Specific Aim 2 will look to identify cellular pathways affected by SM induced injury. These studies will validate the use of the bioprinted skin as a viable ex vivo model of SM toxicity which will enable high precision analysis, including real-time monitoring and -omics to elucidate the sequence and mechanism of sulfur mustard skin injuries. Furthermore, it suggests that the bioprinted skin can be developed into a general surrogate of human skin pathophysiology useful in studying other types of insults. Ultimately, we believe that this system will identify biomarkers of exposure and therapeutic efficacy, as well as serving as a useful modality to discovery and optimize medical countermeasures for a range of chemical and biological weapons.
Sulfur Mustard (SM) remains a significant threat to civilian and military populations, and current animal and in vitro models to date do not fully replicate human physiology. Since the goal of an in vitro 3D skin model is to replicate the authentic anatomy and physiology of native skin, there is an immense need to develop bioengineered skin with multiple cell types and appropriate physiological potential. In this project, we will address this need by bioprinting skin with multiple cell types and then model exposure to the known chemical vesicant sulfur mustard (SM), with the ultimate goal of showing the full utility of the bioprinted skin in elucidating biochemical and pathophysiological pathways in an effort to discover biomarkers and medical countermeasures.