Distinct SARS-CoV-2 specific NLRP3 and IL-1β responses in T cells of aging patients during acute COVID-19 infection

Inhibition of RACK1-Mediated NLRP3 Oligomerization (Active Conformation) Ameliorates Acute Respiratory Distress Syndrome

Aberrant activation of the NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome contributes to the pathogenesis of fatal and perplexing pulmonary diseases. Although pharmacological inhibition of the NLRP3 inflammasome brings potent therapeutic effects in clinical trials and preclinical models, the molecular chaperones and transition governing its transformation from an auto-suppressed state to an active oligomer remain controversial. Here, this work shows that sesquiterpene bigelovin inhibited NLRP3 inflammasome activation and downstream pro-inflammatory cytokines release via canonical, noncanonical, and alternative pathways at nanomolar ranges. Chemoproteomic target identification discloses that bigelovin covalently bound to Cys168 of RACK1, disrupting the interaction between RACK1 and NLRP3 monomer and thereby suppressing NLRP3 inflammasome oligomerization in vitro and in vivo. Bigelovin treatment significantly alleviates the severity of NLRP3-related pulmonary disorders in murine models, such as LPS-induced ARDS and silicosis. These results consolidated the intricate role of RACK1 in transiting the NLRP3 state and provided a new anti-inflammatory lead and therapy for NLRP3-driven diseases.

Immune Checkpoint Inhibitors in Geriatric Oncology

PURPOSE OF REVIEW

This manuscript will update prior reviews of immune checkpoint inhibitors (ICIs) in light of basic science, translational, and clinical discoveries in the field of cancer immunology and aging.

RECENT FINDINGS

ICIs have led to significant advancements in the treatment of cancer. Landmark trials of ICIs have cited the efficacy and toxicity experienced by older patients, but most trials are not specifically designed to address outcomes in older patients. Underlying mechanisms of aging, like cellular senescence, affect the immune system and may ultimately alter the host's response to ICIs. Validated tools are currently used to identify older adults who may be at greater risk of developing complications from their cancer treatment. We review changes in the aging immune system that may alter responses to ICIs, report outcomes and toxicities in older adults from recent ICI clinical trials, and discuss clinical tools specific to older patients with cancer.

Progranulin promotes regulatory T cells plasticity by mitochondrial metabolism through AMPK/PGC-1α pathway in ARDS

As the aging population increases, the focus on elderly patients with acute respiratory distress syndrome (ARDS) is also increasing. In this article, we found progranulin (PGRN) differential expression in ARDS patients and healthy controls, even in young and old ARDS patients. Its expression strongly correlates with several cytokines in both young and elderly ARDS patients. PGRN has comparable therapeutic effects in young and elderly mice with lipopolysaccharide-induced acute lung injury, manifesting as lung injury, apoptosis, inflammation, and regulatory T cells (Tregs) differentiation. Considering that Tregs differentiation relies on metabolic reprogramming, we discovered that Tregs differentiation was mediated by mitochondrial function, especially in the aged population. Furthermore, we demonstrated that PGRN alleviated the mitochondrial damage during Tregs differentiation through the AMPK/PGC-1α pathway in T cells. Collectively, PGRN may regulate mitochondria function to promote Tregs differentiation through the AMPK/PGC-1α pathway to improve ARDS.