Table I.

Identification of exosomal proteins by MALDI-TOF-MSa

BandTotal No. of PeptidesbProtein Identified (National Center for Biotechnology Information accession number)% of the Proteinc CoveredEstimated Protein Molecular Mass (kDa)
111CD13/animopeptidase N (NP032512)13%109.6
39Ribosomal protein S6 kinase (NP033123)13%81.6
418Annexin VI (lipocortin VI) (P68)(P14824)34%75.7
64CDC25 (P48967)14%50
75γ-actin-like protein (AAF08293)25%43.6
86γ-actin (CAA31455)23%41
96Cytoplasmic β-actin (CAA27396)18%39.1
  • a As shown in Fig. 8, bands indicated by arrows were excised and trypsin digested, and the resulting peptides were analyzed by MALDI-TOF-MS as described in Materials and Methods.

  • b Total number of peptides used for comparison with the database. NI, Nonidentified.

  • c Sequence of amino acids matching the identified protein.