Low DNA damage in peripheral lymphocytes of healthy elderly individuals with inverted CD4:CD8 ratio

: Dorneles Gilson Pires, Heuser Vanina, de Andrade Vanessa M., Vilela Ceresér Thalis, da Silva Juliana, Dalberto Daiana, Chies José Artur, Peres Alessandra

Publisher: ELSEVIER SCIENCE BV

: 2019

: International Immunopharmacology

: INTERNATIONAL IMMUNOPHARMACOLOGY

: INT IMMUNOPHARMACOL

: 67

: 483

: 486

: 4

: 1567-5769

DOI: https://doi.org/10.1016/j.intimp.2018.12.060

The aim of this study was to evaluate the DNA damage in peripheral lymphocytes and the frequencies of CD8 + T cells expressing CD25, CD28 and CD45ro in aged individuals with inverted CD4:CD8 ratio. Blood samples of elderly individuals (aged > 65) with normal CD4:CD8 ratio (n = 8) and inverted CD4:CD8 ratio (n = 8) were collected to identify the expression of CD25 +, CD28 + and CD45ro + in CD8 + T cells. DNA damage index was evaluated by the alkaline comet assay which was performed in lymphocytes treated with different concentrations of methyl methanesulfonate (MMS) (control non-treatment, 2 x 10(-5) M, 4 x 10(-5) M) for 1, 2 or 24 h. Elderly individuals with inverted CD4:CD8 ratio presented low frequency of CD8 + CD28 +. Moreover, low DNA damage was observed in lymphocytes of elderly with inverted CD4:CD8 ratio in different doses of MMS. Aged individuals with inverted CD4:CD8 ratio presented lower DNA damage events in peripheral lymphocytes, suggesting a resistance for cell death in T cells of individuals with immune risk profile.