The extracellular release of DNA and HMGB1 from Jurkat T cells during in vitro necrotic cell death

• Published in: Innate immunity (London, England) Vol. 18; no. 5; pp. 727 - 737
• Main Authors: Beyer, Christian, Stearns, Nancy A, Giessl, Adreas, Distler, Jörg HW, Schett, Georg, Pisetsky, David S
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.10.2012
• Subjects: Apoptosis; Cell Separation; DNA; DNA - immunology; DNA - metabolism; Ethanol; Ethanol - adverse effects; Extracellular Space - immunology; Extracellular Space - metabolism; Flow Cytometry; Freeze-thawing; Freezing - adverse effects; Heat; HMGB1 protein; HMGB1 Protein - immunology; HMGB1 Protein - metabolism; Hot Temperature - adverse effects; Humans; Hydrogen peroxide; Hydrogen Peroxide - adverse effects; Immunity, Innate; Jurkat Cells; Kinetics; Lymphocytes T; Necrosis; Necrosis - etiology; Necrosis - immunology; Nuclease; Receptors, Pattern Recognition - immunology; Receptors, Pattern Recognition - metabolism; Western blotting; Alarmin; HMGB1; necrosis; DNA; immune activation
• ISSN: 1753-4259; 1753-4267; 1743-2839; 1753-4267
• DOI: 10.1177/1753425912437981

In innate immunity, dead and dying cells release internal constituents that can serve as damage-associated molecular patterns (DAMPs) or alarmins. This release occurs more abundantly during necrosis than apoptosis and may account for the differences in the immunologic properties of these death forms. To elucidate DAMP release in necrosis, we compared the levels of two nuclear molecules (DNA and HMGB1, a non-histone protein with alarmin activity) in media following necrosis of Jurkat T cells by freeze-thawing, ethanol, heat or hydrogen peroxide treatment. In our experiments, DNA release was measured by fluorimetry with the dye PicoGreen, while HMGB1 was measured by Western blotting. As the results of our study show, each form of necrosis is associated with a distinct pattern of DNA and HMGB1 release with respect to kinetics and amounts. Of these, freeze-thawing produced the highest and most rapid increase in HMGB1 and DNA levels, although the released DNA was subject to nuclease digestion; in addition, freeze-thawing led to the production of particles measured by flow cytometry. Together, these results indicate that experimental necrosis leads to diverse patterns of nuclear molecule release which could affect their immunologic activity.