Direct In-Bone Protein Digestion With Subsequent LC Separation and Trap Ion Mobility MS Detection of Released Peptides as an Effective Tool for the Proteomic Characterization of Bone Tissues.

Common pathological changes in bone tissues like osteomas or exostoses remain not fully understood at the molecular level due to the difficulties in analyzing bone tissues in which they occur. Therefore, new rapid and powerful techniques are needed that could become routine tools for such analysis. The primary aim of this study was to evaluate whether direct in-bone tryptic protein digestion followed by LC separation and trap ion mobility MS detection and identification of released peptides is able to identify sufficient numbers of proteins in above mentioned bone tissues. The second aim was to verify whether the mathematical analysis of the obtained MS data would have a potential to distinguish pathological and control healthy bone tissues. It turned out that this approach made possible to identify altogether 4810 proteins in samples of control healthy skull bone tissues, 6284 proteins in pathological skull bone tissues, and 3000 proteins in mandibular bone tissues. Mathematical analysis of obtained MS data enabled to discriminate control healthy and pathological skull bone tissues samples with accuracy of 87%. Thus, the reported approach seems to have a high potential for routine and effective characterization of bone tissues, in which pathological changes like exostoses or osteomas may occur. Data are available via ProteomeXchange with identifier PXD065656.