Peripheral double negative T: A look at senescent Cubans.

INTRODUCTION: Age-related changes in the immune system are called immunosenescence. Within the T lymphocytes is the subpopulation of double negative (DNT) peripheral lymphocytes that are immunomodulators of the immune response, based on their ability to suppress the functions of simple positive T cells and their cytotoxicity for tumor cells and those infected by viruses. OBJECTIVE: To determine the frequency of peripheral DNT lymphocytes in older Cuban adults. METHODS: A cross-sectional study was carried out in 30 older adults, residents in Cuba. DNT lymphocytes in peripheral blood were quantified by flow cytometry. A Beckman Coulter Gallios flow cytometer was used for data reading and analysis. Percentage values mean and standard deviation were used. The Chi-square was used to relate the percentage values of DNT and comorbidities. It was considered statistically significant if p ≤ 0.05. RESULTS: There was a predominance of women who represented 70 %. No older adult with low values of DNT lymphocytes was reported. Women with high percentage and absolute values of DNT lymphocytes prevailed in relation to men. In the group ≥80 years, high values in % and absolute values of DNT lymphocytes predominated. The high percentage values of DNT cells were mainly related to cardiovascular disease, and predominated in the elderly of ≥80 years old; who presented respiratory and skin infections, fundamentally. The percentage normal value in the group < 80 years was significant (p = 0.0198). The Chi-square value was 0,5995. CONCLUSIONS: Most older adults who exhibited high percentage and absolute values of DNT lymphocytes, or a tendency to them, had some associated comorbidity, an idea that suggests that DNT cells participate in immune surveillance, defense and homeostasis based on their double identity, that is, its pathogenic or immunosuppressive phenotype according to the specific immunological microenvironment.

Immunophenotypic characterization of B1a lymphocytes in Cuban older adults.

INTRODUCTION: B1a lymphocytes are characterized by having a high capacity for self-renewal and production of natural antibodies, in a T-independent manner. There are differences in both the number and composition of mature B lymphocytes throughout life, due to the phenomenon of immunosenescence. OBJECTIVE: To characterize the immunophenotype of B1a lymphocytes in older Cuban adults with a simplified CD19CD20CD5 panel. METHODS: A cross-sectional study was conducted in 30 institutionalized Cuban older adults. Characterization of CD19 + CD5+, CD20 + CD5+, and CD19 + CD20+ B lymphocytes in peripheral blood was performed by flow cytometry. For the reading and analysis of the biological samples, a flow cytometer, Beckman Coulter, Gallios, was used. A Microsoft Excel database was created with the information obtained. The sample was divided by sex and age. The data were processed using the statistical program GraphPadPrism version 6.00 using the percentage values and the median for the sample description. RESULTS: The elderly aged 80 years and over showed a decrease in the absolute count of CD19 + CD20+ B lymphocytes, as well as in the percentage and absolute count of CD19 + CD5+ B lymphocytes. On the other hand, they presented higher absolute counts of CD20 + CD5+ lymphocytes in relation to those of the <80-year-old group. Women showed higher absolute counts of CD19 + CD5+, CD20 + CD5+, and CD19 + CD20+ B lymphocyte populations. CONCLUSIONS: The immunophenotypic characterization of B1a lymphocytes in older Cuban adults is similar to that reported by other researchers. Both age and sex influence the absolute count of these cells, being higher in women under 80 years of age.

Immunophenotypic characterization of double positive T lymphocytes in Cuban older adults.

INTRODUCTION: Immunosenescence is the functional deterioration of the immune system during natural aging that mainly affects T lymphocytes, within which is the subpopulation of peripheral double positive T lymphocytes that are immunomodulators of the immune response. They are increased in older adults and play a fundamental role in the immunopathogenesis of autoimmune diseases, viral infections and neoplasms. OBJECTIVE: To characterize the immunophenotype of peripheral double positive T lymphocytes in Cuban older adults. METHODS: A cross-sectional study was carried out in 30 older adults residing in Cuba. Peripheral blood double positive T lymphocytes were quantified by flow cytometry. The reading was done on a Beckman Coulter Gallios flow cytometer. A Beckman Coulter Gallios flow cytometer was used for data analysis. Percentage values, median and standard deviation were used. RESULTS: There was a predominance of women who represented 70%. No older adults with low values of double positive T lymphocytes were reported. Women with high percentage and absolute values of DPT lymphocytes predominated in relation to men. Among the high percentage values and the absolute value of DPT lymphocytes, the group ≥80 years prevailed. CONCLUSIONS: Most of the older adults who exhibited high percentage and absolute values of DPT lymphocytes had some associated comorbidity, an idea that suggests that CD4 + CD8+ T cells seem to play an important role in peripheral sites as powerful immunosuppressants or as cells with high cytotoxic potential.