CD4+ T regulatory cells are more resistant to DNA damage compared to CD4+ T effector cells as revealed by flow cytometric analysis

• Published in: Cytometry. Part A 2011-11, Vol.79A (11), p.903-911
• Main Authors: Winzler, Claudia, Fantinato, Margherita, Giordan, Marco, Calore, Elisabetta, Basso, Giuseppe, Messina, Chiara
• Format: Article
• Language: English
• Subjects: Animal models; Annexin A5 - analysis; Antineoplastic Agents, Phytogenic - pharmacology; Apoptosis; Apoptosis - drug effects; Bcl-2 protein; Bcl-x protein; bcl-X Protein - genetics; bcl-X Protein - metabolism; Cancer; Caspase 3 - genetics; Caspase 3 - metabolism; CD4 antigen; CD45RA antigen; Cell culture; Cell Proliferation - drug effects; Cells, Cultured; Differentiation; DNA damage; DNA Damage - drug effects; Effector cells; Etoposide - pharmacology; Flow cytometry; Flow Cytometry - methods; FoxP3; Gene Expression; Genotoxicity; Humans; Immunoregulation; Leukocyte Common Antigens - analysis; Lymphocytes T; Organ Specificity; Proto-Oncogene Proteins c-bcl-2 - genetics; Proto-Oncogene Proteins c-bcl-2 - metabolism; Staining and Labeling - methods; T-Lymphocytes, Cytotoxic - cytology; T-Lymphocytes, Cytotoxic - drug effects; T-Lymphocytes, Cytotoxic - metabolism; T-Lymphocytes, Regulatory - cytology; T-Lymphocytes, Regulatory - drug effects; T-Lymphocytes, Regulatory - metabolism; Treg
• ISSN: 1552-4922; 1552-4930; 1552-4930
• DOI: 10.1002/cyto.a.21132

A number of apoptotic stimuli produce a different response by CD4+ regulatory and effector lymphocytes. So far, little is known concerning the sensitivity of CD4+ regulatory T cells (Treg) to genotoxic agents. Observations from a mouse model suggest that Treg are more resistant to DNA damage compared to CD4+ T effector cells (Teff). By flow cytometry we analysed the apoptotic response to genotoxic stimuli in culture, comparing Treg and Teff. CD4+ regulatory lymphocytes appeared to be more resistant than CD4+ effector lymphocytes. Results of costaining experiments for CD45RA suggest that this dissimilarity is not related to the differentiation to a CD45RA negative phenotype. Further, neither the antiapoptotic protein Bcl‐2 nor Bcl‐xL were found to be expressed in greater amounts by Treg compared to Teff. The differential sensitivity of Treg and Teff to DNA‐damage inducing agents may be of clinical relevance in cancer therapy. © 2011 International Society for Advancement of Cytometry