Raman Microspectroscopy Detects Epigenetic Modifications in Living Jurkat Leukemic Cells

Abstract

Aims: Classical biochemical and molecular methods for discerning cells with epigenetic modifications are often biologically perturbing or even destructive. We wondered whether the noninvasive laser tweezer Raman spectroscopy technique allowed the discrimination of single living human cells undergoing epigenetic modifications. Materials & methods: Human Jurkat leukemic cells were treated with inhibitors of histone deacetylases (trichostatin A and MS-275). Epigenetic changes were monitored through histone electrophoresis, nuclear image cytometry and laser tweezer Raman spectroscopy. Results: Treatment of Jurkat cells with histone deacetylase inhibitors increased histone acetylation and induced chromatin organization changes. Characteristic vibrations, issued from laser tweezer Raman spectroscopy analyses, mostly assigned to DNA and proteins allowed discerning histone deacetylase inhibitor-treated cells from control with high confidence. Statistical processing of laser tweezer Raman spectroscopy data led to the definition of specific biomolecular fingerprints of each cell group. Conclusion: This original study shows that laser tweezer Raman spectroscopy is a label-free rapid tool to identify living cells that underwent epigenetic changes.

KEYWORDS::

• acetylation
• epigenetics
• histone
• MS-275
• Raman microspectroscopy
• trichostatin A

Acknowledgements

The authors wish to thank V Untereiner for her expert technical advice.

Financial & competing interests disclosure

This work was supported by grants from the Comité Départemental de l‘Aube de la Ligue Nationale Contre le Cancer. The authors would like to thank CNRS Projets Exploratoires Pluridisciplinaires for financial support. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

The authors state that they have obtained appropriate institutional review board approval or have followed the principles outlined in the Declaration of Helsinki for all human or animal experimental investigations. In addition, for investigations involving human subjects, informed consent has been obtained from the participants involved.

Additional information

Funding

This work was supported by grants from the Comité Départemental de l‘Aube de la Ligue Nationale Contre le Cancer. The authors would like to thank CNRS Projets Exploratoires Pluridisciplinaires for financial support. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.