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12:43
On-Chip Endothelial Inflammatory Phenotyping
Published on: July 22, 2012
Regional differences in constitutive and induced ICAM-1 expression in vivo
J Panés1, M A Perry, D C Anderson
1Department of Physiology, Louisiana State University Medical Center, Shreveport 71130, USA.
The American Journal of Physiology
|December 1, 1995
Summary
Intercellular adhesion molecule 1 (ICAM-1) is present in all rat organs, with endotoxin challenge significantly increasing its expression, especially in the heart and skeletal muscle. Significant regional variations exist in ICAM-1 expression magnitude and timing following endotoxin exposure.
Area of Science:
- Immunology
- Cell Biology
- Physiology
Background:
- Intercellular adhesion molecule 1 (ICAM-1) plays a crucial role in immune cell adhesion and inflammatory responses.
- Endothelial cells express ICAM-1, which can be modulated by inflammatory stimuli like endotoxin.
- Understanding tissue-specific ICAM-1 expression is vital for comprehending inflammatory processes.
Purpose of the Study:
- To characterize and compare ICAM-1 expression in rat endothelial cells across different tissues.
- To investigate the effects of endotoxin challenge on ICAM-1 expression.
- To identify regional differences in ICAM-1 regulation by endotoxin.
Main Methods:
- Quantification of ICAM-1 expression using radiolabeled monoclonal antibodies (125I-anti-rat ICAM-1 MAb).
- Comparison of ICAM-1 binding in various rat organs under baseline and endotoxin-challenged conditions.
- Assessment of ICAM-1 mRNA induction in response to endotoxin.
Main Results:
- ICAM-1 was constitutively expressed in all examined rat organs, with highest baseline levels in the lung.
- Endotoxin challenge significantly upregulated ICAM-1 in most organs, with the greatest fold-increase observed in heart and skeletal muscle.
- ICAM-1 mRNA induction peaked at 3 hours post-endotoxin and varied in magnitude and duration across tissues.
Conclusions:
- ICAM-1 is constitutively expressed on rat vascular endothelium in all organs.
- Endotoxin induces significant, tissue-specific increases in ICAM-1 expression.
- Regional differences in the magnitude and temporal dynamics of ICAM-1 upregulation are evident.
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