Search results for "telomerase activity"
showing 2 items of 2 documents
B CELL CHANGES IN AGING
2014
The aging of the immune system is a gradual and dynamic process that modifies some immunological functions. These changes are known as “immunosenescence” that have a great impact on immune performance in late life, contributing to the decreased ability of the elderly people to respond to emerging pathogens and to the decreased responsiveness to vaccinations. It is known that the adaptive immune functions are affected in the aged. In particular, with aging, the acquired compartment of the immune system shows significant modifications in both T and B cell branches. Thus, the adaptive immune response of elderly people is qualitatively and quantitatively reduced when compared to that observed i…
Double Negative (CD19+IgG+IgD-CD27-) B Lymphocytes: A New Insight from Telomerase in Healthy Elderly, in Centenarian Offspring, and in Alzheimer’s Di…
2014
Background: We have previously reported the increase of IgD-CD27- (Double Negative, DN) B cell population in the aged. These memory B cells have short telomeres and poor abilities to proliferate in vitro. Here, we investigated whether the low ability of DN B cells to proliferate depends on the expression levels of the CD307d and CD22 inhibitory receptors or whether DN B cells can proliferate and reactivate telomerase by the engagement of both innate and adaptive immune receptors. Methods: Phenotypic analyses were made by using flow cytometry. Quantitative analysis of telomerase activity was made by using a TRAP and a photometric enzyme immunoassay in young, healthy elderly, centenarian offs…