Division of Trauma, Department of Surgery, UC San Diego Health Sciences, 212 Dickinson Street, MC 8236, San Diego, CA 92103, USA.
Department of Plastic Surgery, Shanghai Jiao Tong, University Affiliated Sixth People's Hospital, Shanghai 200233, China.
Int J Mol Sci. 2021 Mar 29;22(7):3551. doi: 10.3390/ijms22073551.
Extracellular vesicles (EVs) have an important role in mediating intercellular signaling in inflammation and affect the kinetics of wound healing, however, an understanding of the mechanisms regulating these responses remains limited. Therefore, we have focused on the use of cutaneous injury models in which to study the biology of EVs on the inflammatory phase of wound healing. For this, the foreign body response using sterile subcutaneous polyvinylalcohol (PVA) sponges is ideally suited for the parallel analysis of immune cells and EVs without the need for tissue dissociation, which would introduce additional variables. We have previously used this model to identify mediators of EV biogenesis, establishing that control of how EVs are made affects their payload and biological activity. These studies in normal mice led us to consider how conditions such as immunodeficiency and obsesity affect the profile of immune cells and EVs in this model using genetically defined mutant mice. Since EVs are intrinsically heterogenous in biological fluids, we have focused our studies on a novel technology, vesicle flow cytometry (vFC) to quantify changes in EVs in mouse models. Here, we show that myeloid-derived immune cells and EVs express proteins relevant in antigen presentation in PVA sponge implants that have distinct profiles in wildtype, immune-deficient (NOD scid) vs. diabetic (Lepr) mice. Together, these results establish a foundation for the parallel analysis of both immune cells and EVs with technologies that begin to address the heterogeneity of intercellular communication in the wound bed.
细胞外囊泡 (EVs) 在炎症中的细胞间信号转导中发挥重要作用，并影响伤口愈合的动力学，但对调节这些反应的机制的理解仍然有限。因此，我们专注于使用皮肤损伤模型来研究 EV 在伤口愈合的炎症阶段的生物学特性。为此，使用无菌皮下聚乙烯醇 (PVA) 海绵的异物反应非常适合于在无需组织解离的情况下平行分析免疫细胞和 EV，因为组织解离会引入其他变量。我们之前使用该模型来鉴定 EV 生物发生的介质，确定控制 EV 产生的方式会影响其有效载荷和生物学活性。这些在正常小鼠中的研究使我们考虑到免疫缺陷和肥胖等情况如何影响这种模型中免疫细胞和 EV 的特征，为此我们使用了遗传定义的突变小鼠。由于 EV 在生物体液中本质上是异质的，因此我们专注于一项新技术，即囊泡流式细胞术 (vFC)，以定量分析小鼠模型中 EV 的变化。在这里，我们表明，髓样来源的免疫细胞和 EV 在 PVA 海绵植入物中表达与抗原呈递相关的蛋白质，在野生型、免疫缺陷型 (NOD scid) 和糖尿病 (Lepr) 小鼠中有不同的特征。总之，这些结果为使用开始解决伤口床中细胞间通讯异质性的技术同时分析免疫细胞和 EV 奠定了基础。
