22 research outputs found
Peripheral blood T-cell signatures from high-resolution immune phenotyping of γδ and αβ T-cells in younger and older subjects in the Berlin Aging Study II
Background Aging and latent infection with Cytomegalovirus (CMV) are thought
to be major factors driving the immune system towards immunosenescence,
primarily characterized by reduced amounts of naïve T-cells and increased
memory T-cells, potentially associated with higher morbidity and mortality.
The composition of both major compartments, γδ as well as αβ T-cells, is
altered by age and CMV, but detailed knowledge of changes to the γδ subset is
currently limited. Results Here, we have surveyed a population of 73 younger
(23–35 years) and 144 older (62–85 years) individuals drawn from the Berlin
Aging Study II, investigating the distribution of detailed differentiation
phenotypes of both γδ and αβ T-cells. Correlation of frequencies and absolute
counts of the identified phenotypes with age and the presence of CMV revealed
a lower abundance of Vδ2-positive and a higher amount of Vδ1-positive cells.
We found higher frequencies of late-differentiated and lower frequencies of
early-differentiated cells in the Vδ1+ and Vδ1-Vδ2-, but not in the Vδ2+
populations in elderly CMV-seropositive individuals confirming the association
of these Vδ2-negative cells with CMV-immunosurveillance. We identified the
highest Vδ1:Vδ2 ratios in the CMV-seropositive elderly. The observed increased
CD4:CD8 ratios in the elderly were significantly lower in CMV-seropositive
individuals, who also possessed a lower naïve and a larger late-differentiated
compartment of CD8+ αβ T-cells, reflecting the consensus in the literature.
Conclusions Our findings illustrate in detail the strong influence of CMV on
the abundance and differentiation pattern of γδ T-cells as well as αβ T-cells
in older and younger people. Mechanisms responsible for the phenotypic
alterations in the γδ T-cell compartment, associated both with the presence of
CMV and with age require further clarification
Peripheral blood T-cell signatures from high-resolution immune phenotyping of γδ and αβ T-cells in younger and older subjects in the Berlin Aging Study II
In vivo amifostine (WR-2721) prevents chemotherapy-induced apoptosis of peripheral blood lymphocytes from cancer patients
Long-term effects of amino-bisphosphonates on circulating gamma-delta T cells
The aim of this study was to explore whether desensitization to the occurrence of the acute-phase response (APR) in patients previously treated with amino-bisphosphonates (N-BPs) is due to a long-lasting reduction in the number of circulating \u3b3\u3b4 T cells. Circulating lymphocyte subpopulation counts were obtained from 63 patients with postmenopausal or senile osteoporosis at baseline and after 2 days and 12 months of the first intravenous (IV) 5 mg zoledronic acid (ZOL) infusion. At baseline both the proportion and absolute number of circulating \u3b3\u3b4 T cells were significantly higher in patients who had never used N-BPs vs. previous users, either oral or IV. A typical APR was observed in none of the patients given IV ZOL a year earlier, in 6 (22 %) of the patients previously treated with oral N-BPs, and in 13 (57 %) of the patients naive to any N-BP treatment. In patients naive to N-BPs, a significant reduction in both total lymphocytes and their subsets was observed 2 days after ZOL infusion; all these changes returned to baseline values 1 year later with the exception of \u3b3\u3b4 T cells, which remained significantly lower in terms of both proportion and absolute number. These results indicate for the first time that both IV and oral N-BP treatments are associated with a long-lasting decrease in circulating \u3b3\u3b4 T cells, and this may explain the lower incidence of APR in patients previously exposed to N-BPs. Other clinical implications of this sustained effect of N-BPs on immune-regulatory cells might be important