title: Cell-based quantitative evaluation of the MTT assay.
abstract: OBJECTIVE
  To analyze the bioreduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) on a per cell basis and evaluate its modulation as a function of different stages of cell metabolism.
  
  
  METHODS
  Following MTT bioreduction, total optical density (TOD), cell area and specific activity (TOD/area) of V79 cells and cultured macrophages were recorded for individual cells by means of digital image analysis. The effect of different serum (0-10% vol/vol) or genistein (0-100 microM) concentrations was used to modulate the MTT-specific activity response.
  
  
  RESULTS
  As cells in culture are heterogeneous in cell size, the contribution of each cell to the total amount of formazan formed per dish is variable. The production of formazan per cell as a result of MTT bioreduction was found to be proportional to cell size.
  
  
  CONCLUSIONS
  Specific MTT-reducing activity was analyzed in phagocytes and nonphagocyte cells, revealing the utility of this variable in evaluating the MTT assay at the single-cell level.
authors: National Research Council and Radiobiology Department, National Laboratories of Research and Service-Conicet, National Atomic Energy Commission, Avda. Gral. Paz 1499, (1650) San Martín, Pcia Buenos Aires, Argentina. beamolin@cnea.gov.ar
authors: Beatriz L
authors: BL
authors: Molinari
authors: Débora R
authors: DR
authors: Tasat
authors: Mónica A
authors: MA
authors: Palmieri
authors: Silvia E
authors: SE
authors: O'Connor
authors: Rómulo L
authors: RL
authors: Cabrini
mesh_terms: D000818:Animals; D004396:Coloring Agents; D003239:Connective Tissue Cells / Q000166:cytology* / Q000378:metabolism* / Q000648:ultrastructure; D006224:Cricetinae; D003581:Cytodiagnosis / Q000379:methods; D003584:Cytological Techniques / Q000379:methods; D003952:Diagnostic Imaging / Q000379:methods; D011992:Endosomes / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D016676:Macrophages, Alveolar / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure; D051379:Mice; D008815:Mice, Inbred Strains; D018613:Microscopy, Confocal; D010084:Oxidation-Reduction; D013778:Tetrazolium Salts / Q000378:metabolism* / Q000493:pharmacokinetics; D013844:Thiazoles / Q000097:blood / Q000378:metabolism* / Q000493:pharmacokinetics
chemical_list: D004396:Coloring Agents; D013778:Tetrazolium Salts; D013844:Thiazoles; C022616:thiazolyl blue