Oxidative stress induces protein and DNA radical formation in follicular dendritic cells of the germinal center and modulates its cell death patterns in late sepsis. Free Radic Biol Med 2011 Apr 15;50(8):988-99
Date
01/11/2011Pubmed ID
21215311Pubmed Central ID
PMC3051032DOI
10.1016/j.freeradbiomed.2010.12.037Scopus ID
2-s2.0-79952450820 (requires institutional sign-in at Scopus site) 27 CitationsAbstract
Profound depletion of follicular dendritic cells (FDCs) is a hallmark of sepsis-like syndrome, but the exact causes of the ensuing cell death are unknown. The cell death-driven depletion contributes to immunoparalysis and is responsible for most of the morbidity and mortality in sepsis. Here we have utilized immuno-spin trapping, a method for detection of free radical formation, to detect oxidative stress-induced protein and DNA radical adducts in FDCs isolated from the spleens of septic mice and from human tonsil-derived HK cells, a subtype of germinal center FDCs, to study their role in FDC depletion. At 24h post-lipopolysaccharide administration, protein radical formation and oxidation were significantly elevated in vivo and in HK cells as shown by ELISA and confocal microscopy. The xanthine oxidase inhibitor allopurinol and the iron chelator desferrioxamine significantly decreased the formation of protein radicals, suggesting the role of xanthine oxidase and Fenton-like chemistry in radical formation. Protein and DNA radical formation correlated mostly with apoptotic features at 24h and necrotic morphology of all the cell types studied at 48h with concomitant inhibition of caspase-3. The cytotoxicity of FDCs resulted in decreased CD45R/CD138-positive plasma cell numbers, indicating a possible defect in B cell differentiation. In one such mechanism, radical formation initiated by xanthine oxidase formed protein and DNA radicals, which may lead to cell death of germinal center FDCs.
Author List
Chatterjee S, Lardinois O, Bhattacharjee S, Tucker J, Corbett J, Deterding L, Ehrenshaft M, Bonini MG, Mason RPMESH terms used to index this publication - Major topics in bold
AnimalsBlotting, Western
Caspase 3
Cell Death
DNA
Dendritic Cells
Enzyme-Linked Immunosorbent Assay
Lipopolysaccharides
Male
Mice
Mice, Inbred C57BL
Microscopy, Confocal
Oxidative Stress
Protein Biosynthesis
Sepsis
