Proteomics analysis of early stages of human osteoblasts osteogenic differentiation in vitro

Cellular mechanisms and signaling cascades underlying the early stages of osteoblast progenitors differentiation in adult bone are still not well understood. Therefore, we performed shotgun proteomics analysis of primary culture of isolated human osteoblasts from femur of adult donors in control and on the sixth day of osteogenic differentiation in vitro. This is an early timepoint in which we have observed no extracellular matrix mineralization yet. Nevertheless, for protein extraction we used acidic extraction method which is effective for bones and other mineralized tissues. 1785 proteins identified with at least two unique peptides were included in proteomics analysis. We revealed physiological shift associated with a decrease of cells proliferative activity and extracellular matrix secretion and organization. The obtained data can make a significant contribution to understanding processes of osteogenesis induction to enhance fracture healing.