. With age, the proportion of memory T cells increases, while the proportion and number of naive T cell decreases. Memory T cells are more sensitive to antigenic stimulation and less dependent on co-stimulation signals, as compared to naïve T cells. Differentiation of naïve T cells into memory T cells is accompanied by an increase in T cell reactivity to self-peptide/MHC complexes, which allowed for positive selection of their naïve precursors in the thymus.. We envisage that in geriatric age memory Th1-type autoreactivity leads to age-associated immune hyporeactivity, atherosclerosis and degenerative neuropathology, such as Alzheimer’s and Parkinson’s diseases, whereas autoreactive memory Th2 cells could promote tumorigenesis.. Stimulation of adaptive immunoregulatory mechanisms by polyclonal T-cell vaccination could constrain the development of age-related T-cell autoreactivity surplus. Another approach to immune system “rejuvenation” could involve adoptive cell transfer of naïve T cells with a view to restrain the expansion of pathological memory T cells and support immune responsiveness to novel antigenic challenges. The proposed concept conjectures the occurrence of a hard-wired immunological clock that could determine the duration of life, which theoretically could be subject to immune-based therapy.
Inhibition of ABCG2 efflux pumps renders the Mycobacterium tuberculosis hiding in mesenchymal stem cells responsive to antibiotic treatment.
December 7, 2020
Acute allergic reaction following cutaneous leishmaniosis (CL) transmission in Kashan, central Iran: a case report.
November 2, 2020
October 29, 2020
- ACC 2020The American College of Cardiology decided to cancel ACC.20/WCC due to COVID-19, which was scheduled to take place March 28-30 in Chicago. However, ACC.20/WCC Virtual Meeting continues to release cutting edge science and practice changing updates for cardiovascular professionals on demand and free through June 2020.
- ENDO: 2020ENDO 2020 Annual Conference has been canceled due to COVID-19. Here are highlights of emerging data that has still been released. Keep an eye out for ENDO Online 2020, which will take place from June 8 to 22.
- AAN 2020Due to the global COVID-19 pandemic, the American Academy of Neurology had to cancel the AAN’s Annual Meeting originally scheduled for April 25–May 1, 2020, in Toronto.