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Triggering Cell Stress and Death Using Conventional UV Laser Confocal Microscopy
Published on: February 3, 2017
UV-B irradiated cell lines execute programmed cell death in various forms
M Hagenhofer1, H Germaier, C Hohenadl
1Institute of Clinical Immunology and Rheumatology, Department of Medicine III, Friedrich-Alexander-University, Erlangen-Nuremberg, Erlangen, Germany.
Apoptosis : an International Journal on Programmed Cell Death
|December 4, 2003
Summary
UV-B irradiation induces apoptosis markers in most cell lines, but not all. Some cells show atypical responses, highlighting the need for comprehensive apoptosis detection methods.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Apoptosis, or programmed cell death, is crucial for development and tissue homeostasis.
- UV-B radiation is a known inducer of cellular damage and apoptosis.
- Standard apoptosis detection methods may not capture all forms of programmed cell death.
Purpose of the Study:
- To investigate UV-B induced apoptosis markers across diverse cell lines.
- To evaluate the reliability of standard apoptosis assays in different cellular contexts.
- To explore novel methods for DNA fragmentation analysis.
Main Methods:
- UV-B irradiation of various cell lines.
- Assessment of cellular morphology, phosphatidylserine (PS) exposure (annexin-V binding), DNA fragmentation (oligonucleosomal and high-molecular-weight), and nuclear changes (hypochromia, TUNEL assay).
- Development of a new method for isolating high-molecular-weight (hmwt) DNA fragments.
Main Results:
- Most cell lines exhibited typical apoptosis markers like PS exposure, DNA fragmentation, and morphological changes after UV-B irradiation.
- Raji and HaCaT cells showed no oligonucleosomal DNA fragmentation.
- HaCaT cells displayed other apoptosis features, while Raji cells showed atypical DNA fragmentation and hypochromia but underwent growth arrest with PS exposure.
Conclusions:
- UV-B induced programmed cell death exhibits cell-type-specific variations.
- Absence of oligonucleosomal DNA fragmentation or chromatin condensation does not exclude programmed cell death.
- Comprehensive apoptosis detection is necessary due to diverse cellular responses.
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