Figure 2.

Efficiency of SDE extraction and quantitative characteristics of protein profiles. All identified proteins have been submitted to the ExoCarta database and GO classification system. (a) Western blots showing enrichment of the exosome marker CD63 and ALIX in exosome pellets but not in the supernatants of pooled serum samples after ultracentrifugation. Coomassie brilliant blue staining was used as a control to assess standardized loading. (b) Venn diagram showing the overlap of identified proteins with ExoCarta proteins (5,409; Release date: 29 July 2015). (c–e) The six most enriched categories and the enrichment significance (−log (p‐value), p < .05) of identified proteins in cellular components (c), molecular functions (d), and biological process (e) categories. The percentage of proteins identified in each category is indicated. “S1” refers to pooled serum from Aged normal volunteers, “S2” refers to pooled serum from Aged osteopenia patients, “S3” refers to pooled serum from Aged osteoporosis patients