Single Cell Analysis of Switch-Like Induction of CYP1A1 in Liver Cell Lines

Details

• Personal Author:
  Andersen ME ; Billings RE ; Broccardo CJ ; Chubb LS ; Hanneman WH
• Description:
  The shape of the dose-response curve may vary depending on whether one examines response at a population or a single cell level. Populations of cells may exhibit a graded response whereas single cell responses may have threshold or switch-like behavior. Studies in vivo and in vitro using primary hepatocyte cultures have shown that induction of CYP1A1 in the liver exhibits switch-like behavior in response to PCB 126 (3,3',4,4',5-pentachlorobiphenyl). The goal of the present study was to determine if two liver cell lines (H4IIE rat hepatoma and Hepa 1c1c7 mouse hepatoma) also show switch-like behavior and develop experimental models for studying mechanisms of these switch-like responses. Both cell lines were analyzed via concentration-response and time-course studies using quantitative real-time PCR, revealing a sigmoidal concentration-response curve for CYP1A1 mRNA induction at the population level. To study CYP1A1 protein induction on a single cell level, flow cytometry was employed. In both cell lines the distribution of fluorescence increased with increasing concentrations of PCB 126. The switch behavior was more pronounced in the H4IIE cells than in the Hepa 1c1c7 cells, exhibiting a well-defined shift of induction from the "off" to the "on" state. The concentration-response curve at the single cell level appeared more switch-like with two populations of cells-basal levels and maximally induced. Immunocytochemistry studies of individual cells also support these conclusions. Our data support the hypothesis that PCB 126 induces CYP1A1 in a switch-like fashion in H4IIE rat hepatoma cells. These cells can now be used to study the mechanism of the biological switch. [Description provided by NIOSH]
• Subjects:
  Animals Cells, Cultured Chemistry Cytotoxins Digestive System Liver Occupational Health Radiation Dosimeters Safety
• Keywords:
  Animal-studies Author Keywords: PCB Cell-biology Cell-cultures Cell-function Cell-metabolism Cell-morphology Cell-transformation Cellular-function Cellular-reactions Cellular-structures Chemical-composition Chemical-inhibition Chemical-properties Chemical-reactions Chemical-structure Chemical-synthesis CYP1A1 Cytotoxicity Dose-response Dosimetry Flow Cytometry H4IIE Hepa 1c1c7 Liver-cells Liver-function Liver-tissue Switch

  More +
• ISSN:
  1096-6080
• Document Type:
  Text
• Funding:
  Cooperative Agreement
• Genre:
  Journal Article
• Place as Subject:
  Colorado ; North Carolina ; OSHA Region 4 ; OSHA Region 8
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  287-294
• Volume:
  78
• Issue:
  2
• NIOSHTIC Number:
  nn:20035684
• Citation:
  Toxicol Sci 2004 Apr; 78(2):287-294
• Contact Point Address:
  C. J. Broccardo, Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado 80523-1680
• Email:
  hanneman@colostate.edu
• CAS Registry Number:
  1,1′-Biphenyl, chloro derivs. (CAS RN 1336-36-3)
• Federal Fiscal Year:
  2004
• Performing Organization:
  Colorado State University - Fort Collins
• Peer Reviewed:
  True
• Start Date:
  20010930
• Source Full Name:
  Toxicological Sciences
• End Date:
  20030929
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:8320d819458f7c3c76de04a8f217d78138ea533cc45cc631c2bd4e1a99f4309bf748a170ea53b1c877d699aab36714bdbfcd7291dbbc90b792252a5ddb762774
• Download URL:
  https://stacks.cdc.gov/view/cdc/187464/cdc_187464_DS1.pdf
• File Type:
  [PDF - 390.05 KB ]