Related Experiment Videos
The liver in transforming growth factor-Beta-1 (TGF-beta 1) null mutant mice
A O Williams1, A D Knapton, A Geiser
1Laboratory of Experimental Pathology, National Cancer Institute, Bethesda, Maryland 20892, USA.
Ultrastructural Pathology
|September 1, 1996
Summary
Transforming growth factor-beta-1 (TGF-beta 1) null mutant mice exhibit liver cell abnormalities, including mitochondrial and Golgi complex changes. These findings reveal TGF-beta 1
Area of Science:
- Hepatology and Molecular Biology
- Cellular Ultrastructure and Organelle Biology
- Immunology and Inflammation
Background:
- Transforming growth factor-beta-1 (TGF-beta 1) null mutant mice develop fatal inflammatory lesions by 3 weeks of age.
- Rapamycin treatment can mitigate inflammation and prolong survival in these mice.
- The hepatic phenotype and cellular changes in TGF-beta 1 deficient mice remain largely uncharacterized.
Purpose of the Study:
- To investigate the hepatic phenotype in TGF-beta 1 null mutant mice.
- To characterize the ultrastructural changes in hepatocytes of these mice.
- To determine the role of TGF-beta 1 in hepatocyte development and organelle regulation.
Main Methods:
- Light and electron microscopy of liver tissues from young and old TGF-beta 1 knockout (KO) and wild-type (WT) mice.
- Histological analysis of inflammatory infiltrates and cellular morphology.
- Ultrastructural examination of mitochondria, Golgi complexes, and other organelles.
- Primary culture of KO hepatocytes for detailed ultrastructural analysis.
Main Results:
- Old KO mice displayed mononuclear cell foci, megalocytosis, and increased mitochondria compared to WT mice.
- Hepatocytes from all KO mice showed enlarged Golgi complexes and increased autolysosomes.
- Intracytoplasmic canaliculi were observed in old KO mice but not in young KO or WT mice.
- Cultured KO hepatocytes exhibited similar ultrastructural changes, with minimal mitochondrial abnormalities.
Conclusions:
- Targeted disruption of the TGF-beta 1 gene induces a distinct ultrastructural hepatocyte phenotype.
- TGF-beta 1 is crucial for the normal development and regulation of subcellular organelles in hepatocytes.
- The study highlights the essential role of TGF-beta 1 in maintaining hepatocyte structure and function, particularly involving mitochondria and Golgi complexes.