Immunosenescence comprises the changes in immunity that come with aging. Both the adaptive and the innate immune system are altered. For example, the aged innate immune system is characterized by an increased basal inflammation (‘inflammaging’) with immune paralysis for specific functions [1]. These age-associated immune alterations are thought to have important clinical implications, ranging from poor response to vaccinations to a lower anti-cancer immune potential and increased risk of sarcopenia, the muscle wasting associated with aging [2].
TRIGG investigates the role of innate-like lymphocytes in sarcopenia with a focus on natural killer T (NKT) cells [3]. Natural killer T cells are an unconventional type of T cells which recognize lipid and hydrophobic peptide antigens presented on CD1d instead of the hydrophilic peptides on MHC recognized by conventional T cells. Upon activation, NKT cells produce a fast pro- or anti-inflammatory cytokine response, depending on the context. Elucidating the role of NKT cells and other innate-like lymphocytes in ageing processes such as sarcopenia, will pave the way for immune-based geroprotective interventions.
[1] T. Fulop, A. Larbi, G. Dupuis, A. Le Page, E.H. Frost, A.A. Cohen, J.M. Witkowski, C. Franceschi, Immunosenescence and Inflamm-Aging As Two Sides of the Same Coin: Friends or Foes?, Frontiers in Immunology 8 (2018).
[2] D. Piber, R. Olmstead, J.H.J. Cho, T. Witarama, C. Perez, N. Dietz, T.E. Seeman, E.C. Breen, S.W. Cole, M.R. Irwin, Inflammaging: Age and Systemic, Cellular, and Nuclear Inflammatory Biology in Older Adults, Journals of Gerontology Series a-Biological Sciences and Medical Sciences 74(11) (2019) 1716-1724.
[3] De Spiegeleer A, Kahya H, Van Den Noortgate N, Wynendaele E, Decruy T, Govindarajan S, et al. An unexpected role for iNKT cells in skeletal muscle homeostasis. In: 10th International Conference on Frailty and Sarcopenia Research (ICFSR 2020), Abstracts. 2020. p. 262–262.