Abstract: Using biomass spectrometry, the protein contents of the mesenchymal stem cell (MSC) lysates were studied, and a quality control method was developed. The protein composition of MSC lysates was analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), then the high-abundance proteins were screened out. Method for the quantification of high-abundance proteins was established using the method of marker peptides, and a methodological investigation was carried out. Through LC-MS/MS analysis, 369 proteins were identified from MSC lysates, among which three high-abundance proteins (Vimentin, Filamin-A, and Annexin A2) were screened out as the evaluation indexes of compositional stability; the quantitative detection of the three high-abundance proteins was achieved by using the method of marker peptides; and the results of the methodological experiments showed that the spiked recoveries were satisfactory, the relative standard deviations of the method repeatability were lower than 3.18%, and the lower limit of detection of the method was at the pg level. The results demonstrated that it was feasible to assess the quality and stability of MSC lysates using high-abundance proteins as markers.

Key words: mesenchymal stem cell lysates, marker peptides, liquid chromatography-tandem mass spectrometry, high abundance protein quantification, quality contro