Proteomes, Their Compositions and Their Sources

Biological samples of human and animal origin are utilized in research for many purposes and in a variety of scientific fields, including mass spectrometry-based proteomics. Various types of samples, including organs, tissues, cells, body fluids such as blood, plasma, cerebrospinal fluid, saliva and semen, can be collected from humans or animals and processed for proteomics analysis. Depending on the physiological state and sample origin, collected samples are used in research and diagnostics for different purposes. In mass spectrometry-based proteomics, body fluids and tissues are commonly used in discovery experiments to search for specific protein markers that can distinguish physiological from pathophysiological states, which in turn offer new diagnosis strategies and help developing new drugs to prevent disease more efficiently. Cell lines in combination with technologies such as Stable Isotope Labeling by Amino Acids in Cell Culture (SILAC) have broader application and are used frequently to investigate the mechanism of a disease or to investigate for the mechanism of a drug function. All of these are important components for defining the mechanisms of disease, discovering new pharmaceutical treatments and finally testing side effects of newly discovered drugs.