title: The influence of uremic high cystatin C concentration on neutrophil apoptosis and selected neutrophil functions isolated from healthy subjects.
abstract: BACKGROUND
  Cystatin C (cC) is a cysteine protease inhibitor that may influence immune response. Our aim was to test the effect of a high concentration of cC, characteristic for uremic patients, on neutrophil (PMN) apoptosis and respiratory burst, as well as the cC secretion from PMNs stimulated with proinflammatory cytokines.
  
  
  METHODS
  PMNs from 35 healthy volunteers aged 27-61 years were cultured in presence of cC, IL-1beta or TNF-alpha. The percentage of apoptotic cells based on DNA depletion, Fas, FasL and caspase -3 expression were assessed. CC concentrations were determined by ELISA test. The influence of cC on spontaneous, fMLP-, PMA- or OZ-induced burst response of PMNs was tested using chemiluminescence.
  
  
  RESULTS
  PMN cultured in the presence of cC resulted in a significant drop in apoptotic cell percentage (38% [11%; 65%]) compared both to control (70% [29%; 92%], and to the cells cultured with TNF-alpha (58% [24%; 85%]). These differences were not accompanied by Fas, FasL and caspase-3 expression changes. Spontaneous, fMLP- and PMA-stimulated oxidative burst of PMNs preincubated with cC were significantly downregulated. IL-1beta markedly diminished and TNF-alpha significantly increased cC concentration in culture supernatants.
  
  
  CONCLUSIONS
  The presented results suggest that antiapoptotic activity of cC results from its inhibitory effect on ROS production. Thus, the higher concentration of cC characteristic for uremic patients may modulate acute inflammation through maintaining PMN longevity and inhibiting their respiratory burst and proinflammatory cytokine-related changes in cC release from PMNs.
authors.affiliation: Department of Pathophysiology and Immunopathology of Exercise, Medical University, Lodz, Poland. ewamajew@wp.pl
authors.forename: Ewa
authors.initials: E
authors.lastname: Majewska
authors.forename: Natalia
authors.initials: N
authors.lastname: Wittek
authors.forename: Jacek
authors.initials: J
authors.lastname: Rysz
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Baj
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3 / Q000378:metabolism; D019069:Cell Respiration / Q000187:drug effects; D002469:Cell Separation; D002478:Cells, Cultured; D055316:Cystatin C / Q000378:metabolism*; D053222:Fas Ligand Protein / Q000378:metabolism; D005260:Female; D006262:Health; D006801:Humans; D053583:Interleukin-1beta / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects / Q000201:enzymology / Q000473:pathology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D014511:Uremia / Q000378:metabolism*
chemical_list: D055316:Cystatin C; D053222:Fas Ligand Protein; D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D009240:N-Formylmethionine Leucyl-Phenylalanine; D053148:Caspase 3; D013755:Tetradecanoylphorbol Acetate