Extracellular vesicles facilitate intercellular communication by transferring bioactive molecules with the potential to elicit host responses. Raw bovine milk contains functional extracellular vesicles that are taken up by humans. By comparing with extracellular vesicles from unprocessed bovine milk, the impact of pasteurisation, hydrodynamic cavitation treatment, or homogenisation on purity of milk extracellular vesicles isolated by a series of centrifugation steps followed by size-exclusion chromatography was assessed. Extracellular vesicles could be isolated from all four source materials, though to varying extents as evident from Western blots. In particular, homogenisation resulted in co-isolation of non-extracellular vesicle material such as β-casein, β-lactoglobulin, and triacylglycerol. RNA concentrations were highest in extracellular vesicles derived from the three processed source materials, thus indicating co-isolation of other RNA-containing detergent-labile particles in addition to native milk extracellular vesicles. Overall, this study shows that the history of milk processing impacts the purity of milk extracellular vesicles.

细胞外囊泡通过转移具有引发宿主反应潜力的生物活性分子来促进细胞间通讯。生牛乳含有可被人类吸收的功能性细胞外囊泡。通过与来自未加工牛奶的细胞外囊泡进行比较，评估了巴氏杀菌、流体动力学空化处理或均质化对通过一系列离心步骤分离的牛奶细胞外囊泡纯度的影响，然后进行尺寸排阻色谱。细胞外囊泡可以从所有四种来源材料中分离出来，尽管从蛋白质印迹中可以看出不同程度。特别是，均质化导致非细胞外囊泡材料如 β-酪蛋白、β-乳球蛋白和三酰甘油的共同分离。RNA 浓度在源自三种加工源材料的细胞外囊泡中最高，因此表明除了天然牛奶细胞外囊泡之外，还共同分离了其他含 RNA 的洗涤剂不稳定颗粒。总的来说，这项研究表明牛奶加工的历史影响牛奶细胞外囊泡的纯度。