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Updated: Jul 18, 2026
12:17
Detection and Isolation of Apoptotic Bodies to High Purity
Published on: August 12, 2018
Early contact stage of apoptosis: its morphological features and function
Etheri Mikadze1, Teo Mamatsashvili
1Laboratory of Developmental Biology, Iv. Javakhishvili Tbilisi State University, Tbilisi, Georgia. etherymikadze@yahoo.com
Thescientificworldjournal
|January 2, 2007
Summary
Researchers identified a novel early contact stage in apoptosis, revealing that apoptotic cells may transfer substances to neighboring cells, potentially influencing their function and proliferation beyond simple cell death.
Area of Science:
- Cell Biology
- Developmental Biology
- Hepatology
Background:
- Apoptosis, or programmed cell death, is crucial for development and tissue homeostasis.
- Early morphological features of apoptosis have remained largely undetermined.
- Understanding the initial stages of apoptosis is key to deciphering its full biological role.
Purpose of the Study:
- To identify and characterize the early morphological features of apoptosis in hepatocytes and hepatoblasts.
- To investigate the cellular interactions during the initial phases of apoptosis.
- To explore potential non-degradative functions of apoptotic cells.
Main Methods:
- Utilized semi- and ultrathin sectioning techniques.
- Examined liver tissues from intact embryos and young rats.
- Applied cycloheximide treatment to induce and study apoptosis.
Main Results:
- Identified an early 'contact stage' of apoptosis characterized by ribosome agglutination, nucleolar elimination, and cytoplasmic changes.
- Observed close cell-to-cell contact during this early stage, with potential for nucleolus reappearance and increased polysomes.
- Evidence suggests intercellular communication via gap junctions and micropinocytosis between apoptotic and neighboring cells.
Conclusions:
- Apoptosis involves an early contact stage with distinct morphological and functional characteristics.
- Apoptotic cells may actively transfer newly synthesized substances to adjacent cells.
- The function of apoptosis may extend beyond cell elimination to include intercellular signaling and regulation of neighboring cell activity.
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