Inflammation and aging: signaling pathways and intervention therapiesXia Li, Chentao Li, Wanying Zhang et al.|Signal Transduction and Targeted Therapy|2023 Aging is characterized by systemic chronic inflammation, which is accompanied by cellular senescence, immunosenescence, organ dysfunction, and age-related diseases. Given the multidimensional complexity of aging, there is an urgent need for a systematic organization of inflammaging through dimensionality reduction. Factors secreted by senescent cells, known as the senescence-associated secretory phenotype (SASP), promote chronic inflammation and can induce senescence in normal cells. At the same time, chronic inflammation accelerates the senescence of immune cells, resulting in weakened immune function and an inability to clear senescent cells and inflammatory factors, which creates a vicious cycle of inflammation and senescence. Persistently elevated inflammation levels in organs such as the bone marrow, liver, and lungs cannot be eliminated in time, leading to organ damage and aging-related diseases. Therefore, inflammation has been recognized as an endogenous factor in aging, and the elimination of inflammation could be a potential strategy for anti-aging. Here we discuss inflammaging at the molecular, cellular, organ, and disease levels, and review current aging models, the implications of cutting-edge single cell technologies, as well as anti-aging strategies. Since preventing and alleviating aging-related diseases and improving the overall quality of life are the ultimate goals of aging research, our review highlights the critical features and potential mechanisms of inflammation and aging, along with the latest developments and future directions in aging research, providing a theoretical foundation for novel and practical anti-aging strategies.
Engineered triple inhibitory receptor resistance improves anti-tumor CAR-T cell performance via CD56Fan Zou, Lijuan Lu, Jun Liu et al.|Nature Communications|2019 The inhibitory receptors PD-1, Tim-3, and Lag-3 are highly expressed on tumor-infiltrating lymphocytes and compromise their antitumor activity. For efficient cancer immunotherapy, it is important to prevent chimeric antigen receptor T (CAR-T)-cell exhaustion. Here we downregulate these three checkpoint receptors simultaneously on CAR-T cells and that show the resulting PTL-CAR-T cells undergo epigenetic modifications and better control tumor growth. Furthermore, we unexpectedly find increased tumor infiltration by PTL-CAR-T cells and their clustering between the living and necrotic tumor tissue. Mechanistically, PTL-CAR-T cells upregulate CD56 (NCAM), which is essential for their effector function. The homophilic interaction between intercellular CD56 molecules correlates with enhanced infiltration of CAR-T cells, increased secretion of interferon-γ, and the prolonged survival of CAR-T cells. Ectopically expressed CD56 promotes CAR-T cell survival and antitumor response. Our findings demonstrate that genetic blockade of three checkpoint inhibitory receptors and the resulting high expression of CD56 on CAR-T cells enhances the inhibition of tumor growth.
TRIM28 promotes HIV-1 latency by SUMOylating CDK9 and inhibiting P-TEFbComprehensively elucidating the molecular mechanisms of human immunodeficiency virus type 1 (HIV-1) latency is a priority to achieve a functional cure. As current 'shock' agents failed to efficiently reactivate the latent reservoir, it is important to discover new targets for developing more efficient latency-reversing agents (LRAs). Here, we found that TRIM28 potently suppresses HIV-1 expression by utilizing both SUMO E3 ligase activity and epigenetic adaptor function. Through global site-specific SUMO-MS study and serial SUMOylation assays, we identified that P-TEFb catalytic subunit CDK9 is significantly SUMOylated by TRIM28 with SUMO4. The Lys44, Lys56 and Lys68 residues on CDK9 are SUMOylated by TRIM28, which inhibits CDK9 kinase activity or prevents P-TEFb assembly by directly blocking the interaction between CDK9 and Cyclin T1, subsequently inhibits viral transcription and contributes to HIV-1 latency. The manipulation of TRIM28 and its consequent SUMOylation pathway could be the target for developing LRAs.