Laboratory of Bioengineering and Tissue Regeneration (LABRET), Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, University of Málaga, IBIMA, Málaga, Spain.
Instituto de Immunología Clínica y Terapia Celular (IMMUNESTEM), Málaga, Spain.
PLoS One. 2020 Dec 29;15(12):e0244327. doi: 10.1371/journal.pone.0244327. eCollection 2020.
Limbal stem cells (LSCs) are a quiescent cell population responsible for the renewal of the corneal epithelium. Their deficiency is responsible for the conjunctivization of the cornea that is seen in different ocular pathologies, both in humans and in the canine species. The canine species represents an interesting preclinical animal model in ocular surface pathologies. However, the role of LSCs in physiological and pathological conditions in canine species is not well understood. Our objective was to characterize for the first time the soluble factors and the proteomic profile of the secretome and exosomes of canine LSCs (cLSCs). In addition, given the important role that fibroblasts play in the repair of the ocular surface, we evaluated the influence of the secretome and exosomes of cLSCs on their proliferation in vitro. Our results demonstrated a secretory profile of cLSCs with high concentrations of MCP-1, IL-8, VEGF-A, and IL-10, as well as significant production of exosomes. Regarding the proteomic profile, 646 total proteins in the secretome and 356 in exosomes were involved in different biological processes. Functionally, the cLSC secretome showed an inhibitory effect on the proliferation of fibroblasts in vitro, which the exosomes did not. These results open the door to new studies on the possible use of the cLSC secretome or some of its components to treat certain pathologies of the ocular surface in canine species.
角膜缘干细胞（LSCs）是一种静止的细胞群体，负责角膜上皮的更新。它们的缺乏是导致不同眼部疾病中角膜结膜化的原因，这在人类和犬种中都有发生。犬种是眼部表面疾病中一种有趣的临床前动物模型。然而，LSCs 在犬种生理和病理条件下的作用尚未得到充分理解。我们的目标是首次对犬 LSCs（cLSCs）的分泌因子和蛋白质组学特征进行表征。此外，鉴于成纤维细胞在眼部表面修复中起着重要作用，我们评估了 cLSCs 的分泌体和外泌体对其体外增殖的影响。我们的研究结果表明，cLSCs 具有高浓度的单核细胞趋化蛋白-1（MCP-1）、白细胞介素-8（IL-8）、血管内皮生长因子-A（VEGF-A）和白细胞介素-10（IL-10）的分泌特征，同时还大量产生外泌体。关于蛋白质组学特征，分泌体中有 646 种总蛋白，外泌体中有 356 种总蛋白，这些蛋白参与了不同的生物学过程。功能上，cLSC 的分泌体显示出对体外成纤维细胞增殖的抑制作用，而外泌体则没有。这些结果为研究 cLSC 分泌体或其某些成分在犬种眼部表面某些疾病的潜在用途开辟了新的研究途径。
