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Lozano-Gil, J. M.

Publications and source records attributed to Lozano-Gil, J. M..

2 recordsLinked to original sources

Inhibition of NLRP1 Inflammasome Activation by Tyrosine Kinase Inhibitors Restores Erythropoiesis in Diamond-Blackfan Anemia Syndrome

Diamond-Blackfan Anemia Syndrome (DBAS) is characterized by impaired erythropoiesis due to dysfunctional ribosome biogenesis and aberrant cellular signaling. Here, we investigate how ribosomal stress-induced activation of the NLRP1 inflammasome modulates erythroid differentiation in DBAS. We demonstrate that FDA/EMA-approved tyrosine kinase inhibitors (TKIs) effectively mitigate defective erythropoiesis in Diamond-Blackfan anemia syndrome (DBAS) by inhibiting NLRP1 inflammasome activation. Specifically, nilotinib enhances erythroid differentiation in K562 cells through suppression of the ZAK/P38/NLRP1/CASP1 axis, leading to increased GATA1 protein levels and upregulation of key erythroid genes involved in iron acquisition, hemoglobin synthesis, and erythrocyte structure. These effects were validated in human CD34+ hematopoietic stem and progenitor cells (HSPCs) and zebrafish models, where nilotinib, along with other TKIs (imatinib, dasatinib, and bosutinib), promoted erythropoiesis at the expense of myelopoiesis and reduced caspase-1 activity. Importantly, in RPS19-deficient zebrafish and human models and HSPCs from patients with DBAS, nilotinib, imatinib and dasatinib rescued defective erythroid differentiation and restored hemoglobin levels. These findings highlight the potential of TKIs to address the erythroid defects observed in ribosomopathies like DBAS. Given the limited treatment options available for DBAS and other congenital anemias, our study provides compelling evidence for repurposing TKIs as a novel therapeutic strategy to alleviate pathological NLRP1 activation and improve erythropoiesis. This work opens new avenues for managing ribosome-related disorders and advancing personalized medicine approaches for hematopoietic diseases.

immunology↗

Macrophage Inflammasome Activation Drives Anti-inflammatory Responses via Neutrophil-Derived ASC Speck Transfer and Gasdermin-Dependent Caspase-1 Inhibition

Inflammasomes are critical components of the innate immune system, traditionally associated with pro-inflammatory responses. While the inflammasome in macrophages has been extensively studied and linked to pyroptosis and cytokine release, the neutrophil inflammasome remains poorly understood. Neutrophil inflammasome activation drives unique outcomes such as NETosis and robust IL-1{beta} production without inducing pyroptosis. In contrast, macrophage inflammasome activation promotes pyroptosis and the release of cytokines like IL-1 and IL-18. Here, using zebrafish models of Salmonella enterica serovar Typhimurium infection and COVID-19-associated cytokine storm syndrome (CSS), we reveal opposing roles of neutrophil and macrophage inflammasomes: neutrophil inflammasomes are pro-inflammatory, whereas macrophage inflammasomes mediate anti-inflammatory responses. We show that Gasdermin E- and Ninjurin-1-mediated cell death in neutrophils releases ASC specks, which are taken up by macrophages. This transfer negatively regulates caspase-1 activity via the C-terminal domain of Gasdermin E, promoting the resolution of inflammation. To our knowledge, this is the first study to reveal the anti-inflammatory role of the macrophage inflammasome, document the in vivo transfer of ASC specks between neutrophils and macrophages, and uncover the negative feedback regulation of the inflammasome by the C-terminal domain of Gsdme. These results offer novel insights into potential therapeutic approaches for hyperinflammatory diseases like bacterial infections and COVID-19-associated CSS.

immunology↗