CAREER: Tissue Engineering Better Cell Therapies for Wound Healing.

慢性伤口是指6周后复发或不能愈合的皮肤损伤。这些伤口在美国影响了650万名患者，由于糖尿病患者、肥胖者和老年人的数量急剧增加，这个数字还在迅速增长--这些人都是伤口愈合受损的人群。间充质干细胞(通常被称为成体干细胞)和胰岛素应用于伤口表面，都显示出治愈否则无法愈合的伤口的希望。间充质干细胞通过分泌促进对伤口愈合至关重要的活动的因子来帮助伤口愈合，如新血管的形成、皮肤成分的产生增加以及清洁伤口和形成疤痕组织的细胞的招募。胰岛素通过将间充质干细胞和皮肤细胞招募到伤口区域来帮助伤口愈合。最近观察到，联合使用间充质干细胞和胰岛素分泌细胞治疗的伤口愈合得比正常快，而且没有疤痕形成，该项目的目的是确定实现观察到的加速愈合和减少瘢痕形成所需的胰岛素类型，并揭示所招募的伤口愈合途径。研究成果有可能通过实现快速愈合来改变伤口护理，从而避免与慢性伤口相关的发病率和死亡率，并通过减少或消除疤痕形成来改善重建和整形手术的结果。该项目的长期教育目标是向未来的工程师展示在不熟悉的环境中进行的组织工程研究，如航空，以激发未来生物医学工程职业的创新思维。为了追求这一目标，该项目的教育目标是将研究原则应用于教学，并开发组织工程研究模块，将研究、教学、指导和学习结合在一起，用于基于生物医学工程课程的本科生研究经验(CURE)。教育和外展的方法是招收女学生，将她们分组，并提供动手研究活动，提供创伤愈合模型，使她们能够制定假设和模型，并提出、进行和展示实验，以加深他们对研究的理解。这些女性将被要求在科学会议上展示她们的研究，并在航空科学俱乐部向K-12年级的学生展示她们的研究。该项目的研究重点是调查间充质干细胞(MSCs)和胰岛素产生细胞(IPC)对伤口愈合及其途径的影响，以及确定细胞-细胞与细胞-伤口相互作用如何控制被包裹细胞的分泌体。该项目是由PI实验室最近的研究推动的，在结合这些细胞后，实现了显著加速(14天比40天)、无疤痕的伤口愈合。该研究计划有四个具体目标。目的1是通过体外研究，剖析IPC和胰岛素在共包裹细胞的存活和功能中的作用，即无论是胰岛素本身、IPC的存在还是改善存活和功能的激素释放。目的2是通过在小鼠体内的研究，剖析IPC和胰岛素在加速伤口愈合中的作用，即产生胰岛素的成纤维细胞是否具有与商业上可获得的分泌额外产物的IPC(RIN-5F和RIN-14B)相同的作用。目的3是通过体外研究，确定与创伤环境诱导的MSC因子释放相比，共包裹促进MSC因子释放的程度，即对MSC存活至关重要的Akt信号通路在与IPC共包裹的MSCs中激活更强，还是在单独输送到伤口处的MSCs中激活。目的4是确定IPC+MSCs减少瘢痕形成的程度，即将这项工作扩展到在猪身上进行的有限研究，因为猪的表皮和真皮类似于人类皮肤，并且愈合速度相当。总而言之，这个项目将研究IPC+MSC创伤愈合中涉及的代谢途径，两个细胞和伤口环境之间的相互作用，以及所学到的经验是否可以应用于其他细胞疗法。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Chronic wounds are skin injuries that recur or fail to heal by 6 weeks. These wounds affect 6.5 million patients in the US and this number is growing rapidly due to a drastic increase in the number of diabetics, the obese, and the elderly--all populations in which wound healing is impaired. Mesenchymal stem cells (commonly known as adult stem cells) and insulin applied to wound surfaces have each shown promise in healing otherwise unhealable wounds. Mesenchymal stem cells assist wound healing by secreting factors that promote actions critical to wound healing, such as new blood vessel formation, increases in the production of skin components, and recruitment of cells that clean wounds and form scar tissue. Insulin assists wound healing by recruiting mesenchymal stem cells and skin cells to the wound area. Motivated by the recent observation that wounds treated with a combination of mesenchymal stem cells and insulin-producing cells healed faster than normal and without scarring, the objective of this project is to identify the type of insulin needed to achieve the observed accelerated healing and reduced scarring and to uncover the wound healing pathways that are recruited. Research results have the potential to transform wound care by enabling rapid healing that would avert the morbidity and mortality associated with chronic wounds and to enhance reconstructive and plastic surgery outcomes by reducing or eliminating scar formation. The project's long-term educational goal is to present future engineers with tissue engineering research in unfamiliar contexts, like aviation, to inspire innovative thinking for future careers in biomedical engineering. In pursuit of this goal, this project's educational objective is to apply research principles to teaching and to develop tissue engineering research modules that integrate research, teaching, mentorship, and learning for use in biomedical engineering course-based undergraduate research experiences (CUREs). The educational and outreach approach is to recruit female students, group them in teams and provide hands-on research activities with wound healing models that will enable them to formulate hypotheses and models, and to propose, conduct, and present experiments that will further their understanding of research. The women will be required to present their research in scientific meetings and to K-12 graders in an aviation science club.The project's research focus is on investigating the impact of mesynchymal stem cells (MSCs) and insulin producing cells (IPCs), both individually and coencapsulated, on wound healing and its pathways, and on identifying how cell-cell vs. cell-wound interactions govern the secretome of encapsulated cells. The project is motivated by recent studies from the PI's lab that achieved dramatically accelerated (14 vs 40 days), scar-free wound healing after combining these cells. The research plan has four specific aims. Aim 1 is to dissect, via in vitro studies, the role of IPCs vs insulin in survival and function of the coencapsulated cells, i.e., whether it is insulin itself, the presence of the IPCs or the hormone release that improves survival and function. Aim 2 is to dissect, via in vivo studies in mice, the role of IPCs vs insulin in the accelerated wound healing, i. e, whether insulin-producing fibroblasts have the same effect as commercially available IPCs (RIN-5F and RIN-14B) that secrete additional products. Aim 3 is to determine the extent, via in vitro studies, that coencapsulation promotes MSC factor release in comparison to MSC factor release elicited by wound environments, i.e., whether the Akt signaling pathway, which is critical to MSC survival, is activated more strongly in MSCs coencapsulated with IPCs or in MSCs delivered singly to wounds. Aim 4 is to determine the extent that IPCs+MSCs reduce scar formation, i.e., to extend the work to a limited study in pigs, which have an epidermis and dermis similar to human skin and heal at a comparable rate. In summary, this project will examine the metabolic pathways involved in IPC+MSC wound healing, the interplay between the two cells and the wound environment, and whether lessons learned can be applied to other cell therapies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.