Homing and memory patterns of human gammadelta T cells in physiopathological situations.
Vgamma9Vdelta2 are a heterogeneous population of T cells and comprise distinct naive, memory and effector populations that can be distinguished on the basis of surface marker expression and effector functions. We review here these recently studied features of Vgamma9Vdelta2 T lymphocyte biology and the roles they play in infectious and autoimmune diseases.
Differential requirements for antigen or homeostatic cytokines for proliferation and differentiation of human Vgamma9Vdelta2 naive, memory and effector T cell subsets.
We have compared four human subsets of Vgamma9Vdelta2 T cells, naive (T(naive), CD45RA(+)CD27(+)), central memory (T(CM), CD45RA(-)CD27(+)), effector memory (T(EM), CD45RA(-)CD27(-)) and terminally differentiated (T(EMRA), CD45RA(+)CD27(-)), for their capacity to proliferate and differentiate in response to antigen or homeostatic cytokines. Cytokine responsiveness and IL-15R expression were low in T(naive) cells and progressively increased from T(CM) to T(EM) and T(EMRA) cells. In contrast, the capacity to expand in response to antigen or cytokine stimulation showed a reciprocal pattern and was associated with resistance to cell death and Bcl-2 expression. Whereas antigen-stimulated cells a…
Human primary macrophages scavenge AuNPs and eliminate it through exosomes. A natural shuttling for nanomaterials.
Abstract The use of nanomaterials is increasing but the real risk associated with their use in humans has to be defined. In fact, nanomaterials tend to accumulate in organs over a long period of time and are slowly degraded or eliminated by the body. Exosomes are nanovesicles actively shuttle molecules, including chemical products and metals, through the body. Macrophages scavenge the body from both organic and inorganic substances, and they use to release high amounts of exosomes. We hypothesized that macrophages may have a role in eliminating nanomaterials through their exosomes. We treated human primary macrophages with 20 nm gold nanoparticles (AuNPs), analyzing the presence of AuNPs in…