REU: Engineered Platforms for Control of Multi-cue Migration

摘要 该项目的目标是使用工程化的细胞外基质环境，利用结构和我- 对细胞外基质的机械控制，以检查细胞对多发性硬化的反应机制 定向迁徙线索。细胞迁移在许多生理和病理过程中起着重要作用。 如伤口愈合、发育和癌症侵袭等。通常，迁移不是简单的随机迁移， 但是通过识别排列好的细胞外基质纤维或硬度梯度而指向目标， 分别产生接触指导和多向趋向性。在许多生物学背景下，这些线索被呈现出来 同时，迫使细胞整合这些信息。例如，硬度的梯度和对齐的胶合- GEN在伤口床内产生，引导真皮成纤维细胞迁移。相似的纤维结构和纹理- 成分刺激癌细胞迁移出肿瘤微环境和包括间质在内的正常细胞 和免疫细胞对肿瘤微环境的影响。虽然对细胞是如何重新启动的已经有了很好的理解 除了个别的定向线索外，几乎对细胞如何整合多个线索和 根据这种整合做出迁移决策。此外，还有一种假设，即联系指导 和耐药是重叠的定向细胞迁移机制，但这还没有得到严格的测试。 从机制上理解多线索定向迁移将需要精细地理解F-2是如何 肌动蛋白和微管网络起作用。事实上，一些证据表明，联系指导和杜罗税- IS可能使用略有不同的F-肌动蛋白网络结构，因为接触指导被认为是由F-肌动蛋白控制的。 肌动蛋白纤维结构，但趋杜性不是。将采用工程方法进行体外环境设计 这允许在2D和3D环境中独立调整接触引导和多向趋向性。进一步- 此外，F-肌动蛋白的分支、捆绑和收缩使细胞更喜欢排列的胶原蛋白纤维。 将测试刚度的一般或梯度。这将揭示涉及的共享或竞争的分子途径 当这两个定向迁移线索单独和一起出现时。了解细胞如何丢失- 格栅对多个线索的响应在包括组织工程在内的几个生物医学领域具有广泛的影响 和疾病治疗学。确定细胞在体外对多种信号的反应将使我们能够预测细胞 在伤口愈合、发育、癌症侵袭和免疫反应中的反应导致候选药物 如癌症或加强伤口愈合和免疫反应的策略。

ABSTRACT The goal of this project is to use engineered extracellular matrix environments leveraging structural and me- chanical control over the extracellular matrix to examine the mechanisms by which cells respond to multiple directional migration cues. Cell migration plays an important role in many physiological and pathological pro- cesses such as wound healing, development and cancer invasion. Frequently migration is not simply random, but directed towards targets through recognition of aligned extracellular matrix fibers or gradients in stiffness, generating contact guidance and durotaxis, respectively. In many biological contexts these cues are presented simultaneously, forcing cells to integrate this information. For instance, gradients of stiffness and aligned colla- gen are generated within the wound bed to direct dermal fibroblast migration. Similar fiber structures and gra- dients stimulate cancer cell migration out of the tumor microenvironment and normal cells including stromal and immune cells towards the tumor microenvironment. While there is a firm understanding of how cells re- spond to individual directional cues, virtually nothing is known about how cells integrate multiple cues and make migrational decisions based on that integration. Furthermore, there is a hypothesis that contact guidance and durotaxis are overlapping directional cell migration mechanisms, but this has not been rigorously tested. Mechanistic understanding of multi-cue directional migration will require a refined understanding of how the F- actin and microtubule networks operates. Indeed, some evidence suggests that contact guidance and durotax- is may use slightly different F-actin network structures, since contact guidance is thought to be governed by F- actin fiber structures, but durotaxis is not. Engineering approaches will be taken to design in vitro environments that allow for independent tuning of contact guidance and durotaxis in both 2D and 3D environments. Further- more, the effect of F-actin branching, bundling and contraction in allowing cells to prefer aligned fibers of colla- gen or gradients of stiffness will be tested. This will uncover shared or competing molecular pathways involved when these two directional migration cues are present in isolation and together. Understanding how cells mi- grate in response to multiple cues has broad impact on several biomedical fields including tissue engineering and disease therapeutics. Determining how cells respond to multiple cues in vitro will allow us to predict cell responses in wound healing, development, cancer invasion and immune response leading to drug candidates as in cancer or strategies to enhance wound healing and immune response.