Perspectives in stem cell proteomics

Stem cells receive broad attention in the scientific literature and in society in general. This has been inspired by their unique properties - the potential to self-renew and to differentiate into multiple lineages. Human embryonic stem cells (hESCs) have the ability to form all cells in the adult body once they receive the proper signals. The capability to control and direct differentiation in vitro would offer opportunities to develop treatments for diseases that cannot be treated today, especially in the area of regenerative medicine, where the aim is to replace damaged tissue. However, there are still many challenges before hESCs can be safely used for clinical applications. Moreover, societal and ethical issues need to be addressed before basic science in this area could be successfully translated into the clinic.The field of proteomics has matured immensely in recent years, now allowing proteome biology investigation at reasonable throughput in all areas of cell biology. Proteomics researchers have started to chart the proteome of individual primary stem cells and stem cell lines and their differentiated derivatives, to define a subset of stem cell-specific proteins, or to identify differentiation-specific proteins that can be used as benchmarks for the intermediate or terminal steps of stem cell differentiation. Importantly, proteomics studies have shown that transcriptome analyses cannot fully explain developmental changes, most likely because they are unable to detect post-translational processes such as protein modifications and protein-protein interactions.At present, stem cell biology and proteomics are both rather specialized scientific domains. Specialists from each field seldom meet. Thus, crucial opportunities may be missed for setting priorities and goals, and for maintaining consistent and optimized standards for research where these fields intersect, essential for an effective comparison of experimental data across different laboratories. In respo