In their report, Kumeda et al. examined Membrane integrity and morphological stability of salivary exosomes using dipeptidyl peptidase IV and CD9 as membrane makers, and Alix and Tsg101 as lumen markers. Neither localization nor levels of these marker proteins were changed in isolated exosomes after long-term storage at 4°C or multiple freeze-thaw cycles. Moreover, intact exosomes could be isolated from whole saliva refrigerated for a month. Components inside the exosomes were stable even after solubilization of membrane components with detergents such as Triton X-100. These results indicate that human saliva-derived exosomes are very stable, maintaining their membrane integrity over a long storage period.