Secretome Analysis of Apoptotic PBMCs Suggests Impact of Released Proteins & Exosomes on Tissue Regeneration; First Study to Evaluate Effects of Radiation Stress on Oxidized Lipid Content of Secretome

In a new study, scientists from the Medical University of Vienna in Austria, together with colleageues, have shown that irradiation stress modulates the release of proteins, lipid-mediators, and extracellular vesicles (EVs) from human peripheral blood monocytes (PBMCs). The researchers suggest that their new findings implicate the use of secretome fractions as valuable material for the development of cell-free therapies in regenerative medicine. The research was reported in an open-access article published online on November 16, 2015 in Scientific Reports. The article is titled “Analysis of the Secretome of Apoptotic Peripheral Blood Mononuclear Cells: Impact of Released Proteins and Exosomes for Tissue Regeneration.” The senior and corresponding author of the article is Hendrik Jan Ankersmit, M.D., of the Department of Thoracic Surgery and the Christian Doppler Laboratory for Cardiac and Thoracic Diagnosis and Regeneration at the Medical University of Vienna. In their article introduction, the authors write that they had previously showed that, when PBMCs were stressed with ionizing radiation, they released paracrine factors that showed regenerative capacity in vitro and in vivo. The current study was designed to characterize the secretome of PBMCs and to investigate its biologically active components in vitro and vivo. The scientists say that bioinformatics analysis revealed that irradiated PBMCs differentially expressed genes that encoded secreted proteins. These genes are primarily involved in (a) pro-angiogenic and regenerative pathways; and (b) the generation of oxidized phospholipids with known pro-angiogenic and inflammation-modulating properties.