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Elias, J. A.

Publications and source records attributed to Elias, J. A..

4 recordsLinked to original sources

Kasugamycin is a novel chitinase 1 inhibitor with strong antifibrotic effects on pulmonary fibrosis

RationalePulmonary fibrosis is a devastating lung disease with few therapeutic options. Chitinase 1 (CHIT1), an 18 glycosyl hydrolase family member, contributes to the pathogenesis of pulmonary fibrosis through regulation of Transforming Growth Factor (TGF)-{beta} signaling and effector function. Therefore, CHIT1 is a potential therapeutic target of pulmonary fibrosis. ObjectivesThis study aimed to identify and characterize a druggable CHIT1 inhibitor with strong antifibrotic activity and minimal toxicity for therapeutic application to pulmonary fibrosis. MethodsExtensive screening of small molecule libraries identified the aminoglycoside antibiotic Kasugamycin as a potent CHIT1 inhibitor. Measurements and Main ResultsElevated levels of CHIT1 were detected in the lungs of patients with pulmonary fibrosis. In vivo bleomycin- and TGF-{beta}-stimulated murine models of pulmonary fibrosis, Kasugamycin showed impressive anti-fibrotic effects in both preventive and therapeutic conditions. In vitro studies also demonstrated that Kasugamycin inhibits fibrotic macrophage activation, fibroblast proliferation and myofibroblast transformation. Null mutation of transforming growth factor beta associated protein 1 (TGFBRAP1), a recently identified CHIT1 interacting signaling molecule, phenocopied antifibrotic effects of Kasugamycin in in vivo lungs and in vitro fibroblasts responses. Kasugamycin inhibits physical association between CHIT1 and TGFBRAP1, suggesting that antifibrotic effect of Kasugamycin is mediated through regulation of TGFBRAP1, at least in part. ConclusionsThese studies demonstrate that Kasugamycin is a novel CHIT1 inhibitor with strong antifibrotic effect that can be further developed as an effective and safe therapeutic drug for pulmonary fibrosis.

immunology

Chitinase 3-like-1 Stimulates PD-L1 and Other Immune Checkpoint Inhibitors

PD-1 and its ligand PD-L1 are major mediators of tumor-induced immunosuppression. Chitinase 3-like-1 (Chi3l1) is induced in many cancers where it portends a poor prognosis and contributes to tumor metastasis. Here we demonstrate that Chi3l1 regulates the expression of PD-L1, PD-L2, PD-1 and LAG3 in melanoma lung metastasis. Chi3l1 stimulates macrophage PD-L1 expression and mediates optimal IFN-{gamma}-stimulated PD-L1 expression via IL-13R2. We also demonstrate that RIG-like helicase innate immune activation suppresses Chi3l1, PD-L1, LAG3 and pulmonary metastasis. At least additive antitumor responses were seen in metastasis models treated simultaneously with individual antibodies against PD-1 and Chi3l1. At least additive cytotoxic T cell-induced tumor cell death was also seen in co-cultures of T and tumor cells treated with antibodies that target Chi3l1 and PD-1. Thus, Chi3l1 contributes to pulmonary metastasis by stimulating the PD1-PD-L1 axis and other checkpoint molecules. The simultaneous targeting of Chi3l1 and the PD-1-PD-L1 axis, represents a promising therapeutic strategy for pulmonary metastasis.

cancer biology

Chitinase 3-like-1 is a Therapeutic Target That Mediates the Effects of Aging in COVID-19

COVID-19 is caused by the SARS-CoV-2 (SC2) virus and is more prevalent and severe in the elderly and patients with comorbid diseases (CM). Because chitinase 3-like-1 (CHI3L1) is induced during aging and CM, the relationships between CHI3L1 and SC2 were investigated. Here we demonstrate that CHI3L1 is a potent stimulator of the SC2 receptor ACE2 and viral spike protein priming proteases (SPP), that ACE2 and SPP are induced during aging and that anti-CHI3L1, kasugamycin and inhibitors of phosphorylation, abrogate these ACE2- and SPP-inductive events. Human studies also demonstrated that the levels of circulating CHI3L1 are increased in the elderly and patients with CM where they correlate with COVID-19 severity. These studies demonstrate that CHI3L1 is a potent stimulator of ACE2 and SPP; that this induction is a major mechanism contributing to the effects of aging during SC2 infection and that CHI3L1 coopts the CHI3L1 axis to augment SC2 infection. CHI3L1 plays a critical role in the pathogenesis of and is an attractive therapeutic target in COVID-19.

immunology

Natural Killer cell activation, reduced ACE2, TMPRSS2, cytokines G-CSF, M-CSF and SARS-CoV-2-S pseudovirus infectivity by MEK inhibitor treatment of human cells

COVID-19 affects vulnerable populations including elderly individuals and patients with cancer. Natural Killer (NK) cells and innate-immune TRAIL suppress transformed and virally-infected cells. ACE2, and TMPRSS2 protease promote SARS-CoV-2 infectivity, while inflammatory cytokines IL-6, or G-CSF worsen COVID-19 severity. We show MEK inhibitors (MEKi) VS-6766, trametinib and selumetinib reduce ACE2 expression in human cells. In some human cells, remdesivir increases ACE2-promoter luciferase-reporter expression, ACE2 mRNA and protein, and ACE2 expression is attenuated by MEKi. In serum-deprived and stimulated cells treated with remdesivir and MEKi we observed correlations between pRB, pERK, and ACE2 expression further supporting role of proliferative state and MAPK pathway in ACE2 regulation. We show elevated cytokines in COVID-19-(+) patient plasma (N=9) versus control (N=11). TMPRSS2, inflammatory cytokines G-CSF, M-CSF, IL-1, IL-6 and MCP-1 are suppressed by MEKi alone or with remdesivir. We observed MEKi stimulation of NK-cell killing of target-cells, without suppressing TRAIL-mediated cytotoxicity. Pseudotyped SARS-CoV-2 virus with a lentiviral core and SARS-CoV-2 D614 or G614 SPIKE (S) protein on its envelope infected human bronchial epithelial cells, small airway epithelial cells, or lung cancer cells and MEKi suppressed infectivity of the pseudovirus. We show a drug class-effect with MEKi to stimulate NK cells, inhibit inflammatory cytokines and block host-factors for SARS-CoV-2 infection leading also to suppression of SARS-CoV-2-S pseudovirus infection of human cells. MEKi may attenuate SARS-CoV-2 infection to allow immune responses and antiviral agents to control disease progression.

cell biology