Acute inflammation alters lung lymphocytes and potentiates innate-like behavior in young mouse lung CD8 T cells, resembling lung CD8 T cells from old mice

Abstract

Inflammation plays a significant role in lung infection including that caused by Mycobacterium tuberculosis (M.tb), where both adaptive and innate lymphocytes can affect infection control. How inflammation affects infection is understood in a broad sense, including inflammaging (chronic inflammation) seen in the elderly, but the explicit role that inflammation can play in regulation of lymphocyte function is not known. To fill this knowledge gap, we used an acute lipopolysaccharide (LPS) treatment in young mice and studied lymphocyte responses, focusing on CD8 T cell subsets. LPS treatment decreased the total numbers of T cells in the lungs of LPS mice, while also increasing the number of activated T cells. We demonstrate that lung CD8 T cells from LPS mice became capable of an antigen independent innate-like IFN-γ secretion, dependent on IL-12p70 stimulation, paralleling innate-like IFN-γ secretion of lung CD8 T cells from old mice. Overall, this study provides information on how acute inflammation can affect lymphocytes, particularly CD8 T cells, which could potentially affect immune control of various disease states.

Mitochondrial Oxidative Stress Regulates FOXP3+ T-Cell Activity and CD4-Mediated Inflammation in Older Adults with Frailty

“…Our results highlight a substantial increase in CD4 inflammation and a reduction in Treg activity in older adults with frailty, pointing to a complex interplay of proinflammatory mechanisms within the immune system. Conventional aging research has often limited its focus to comparing the immune systems of older adults with those of younger individuals, frequently overlooking the molecular changes in immune cells among healthy older adults during natural aging [ 61 , 62 , 63 , 64 ]. Addressing this gap, our study underscores a potential link between diminished grip strength and elevated inflammation in frail adults compared to their healthier counterparts.…”