Biology subjects

Pinilla-Vera, M.

Publications and source records attributed to Pinilla-Vera, M..

4 recordsLinked to original sources

bioRxiv2022

Single-cell transcriptomics reveal hyperacute cytokine and immune checkpoint axis in patients with poor neurological outcomes after cardiac arrest

Neurological injury is a major driver of mortality among patients hospitalized after cardiac arrest (CA). The early systemic inflammatory response after CA is associated with neurological injury and mortality but remains poorly defined. We determine the innate immune network induced by clinical CA at single-cell resolution. Immune cell states diverge as early as 6h post-CA between patients with good or poor neurological outcomes at hospital discharge. Nectin-2+ monocyte and Tim-3+ natural killer (NK) cell subpopulations associate with poor outcomes, and interactome analysis highlights their crosstalk via cytokines and immune checkpoints. Ex vivo studies on peripheral blood cells from CA patients demonstrate that immune checkpoints are a compensatory mechanism against inflammation after CA. IFN{gamma}/IL-10 induce Nectin-2 on monocytes; in a negative feedback loop, Nectin-2 suppresses IFN{gamma} production by NK cells. The initial hours after CA may represent a window for therapeutic intervention in the resolution of inflammation via immune checkpoints.

immunology↗

bioRxiv2021

Single Serine on TSC2 Exerts Biased Control over mTORC1 Activation by ERK1/2 but Not Akt

The mammalian target of rapamycin complex 1 (mTORC1) is tightly controlled by tuberous sclerosis complex-2 (TSC2) that is regulated by phosphorylation from kinases responding to environmental cues. Protein kinase G specifically modifies serine-1365 (S1364, human), and its phosphorylation (or phosphomimetic SE mutant) potently blocks mTORC1 co-activation by pathological stress, while a phospho-silenced (SA) mutation does the opposite. Neither alter basal mTORC1 activity. Here we show S1365 exerts biased control over mTORC1 activity (S6K phosphorylation) modifying ERK1/2 but not Akt-dependent stimulation. Whereas mTORC1 activation by endothelin-1 is potently modified by S1365 status, insulin or PDGF stimulation are unaltered. TSC2-S1365 is also phosphorylated upon ET-1 but not insulin stimulation in a PKG-dependent manner, revealing intrinsic bias. Neither energy or nutrient modulation of mTORC1 are impacted by S1365. Consistent with these results, knock-in mice with either TSC2 SA or SE mutations develop identical obesity, glucose intolerance, and fatty liver disease from a high fat diet. Thus, S1365 provides an ERK1/2-selective mTORC1 control mechanism and a genetic means to modify pathological versus physiological mTOR stimuli.

cell biology↗

bioRxiv2020

Induction of a regulatory myeloid program in bacterial sepsis and severe COVID-19

A recent estimate suggests that one in five deaths globally are associated with sepsis1. To date, no targeted treatment is available for this syndrome, likely due to substantial patient heterogeneity2,3 and our lack of insight into sepsis immunopathology4. These issues are highlighted by the current COVID-19 pandemic, wherein many clinical manifestations of severe SARS-CoV-2 infection parallel bacterial sepsis5-8. We previously reported an expanded CD14+ monocyte state, MS1, in patients with bacterial sepsis or non-infectious critical illness, and validated its expansion in sepsis across thousands of patients using public transcriptomic data9. Despite its marked expansion in the circulation of bacterial sepsis patients, its relevance to viral sepsis and association with disease outcomes have not been examined. In addition, the ontogeny and function of this monocyte state remain poorly characterized. Using public transcriptomic data, we show that the expression of the MS1 program is associated with sepsis mortality and is up-regulated in monocytes from patients with severe COVID-19. We found that blood plasma from bacterial sepsis or COVID-19 patients with severe disease induces emergency myelopoiesis and expression of the MS1 program, which are dependent on the cytokines IL-6 and IL-10. Finally, we demonstrate that MS1 cells are broadly immunosuppressive, similar to monocytic myeloid-derived suppressor cells (MDSCs), and have decreased responsiveness to stimulation. Our findings highlight the utility of regulatory myeloid cells in sepsis prognosis, and the role of systemic cytokines in inducing emergency myelopoiesis during severe bacterial and SARS-CoV-2 infections.

immunology↗

bioRxiv2020

Mechanosensitive activation of mTORC1 mediates ventilator induced lung injury during the acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a highly lethal condition that impairs lung function and causes respiratory failure. Mechanical ventilation maintains gas exchange in patients with ARDS, but exposes lung cells to physical forces that exacerbate lung injury. Our data demonstrate that mTOR complex 1 (mTORC1) is a mechanosensor in lung epithelial cells and that activation of this pathway during mechanical ventilation exacerbates lung injury. We found that mTORC1 is activated in lung epithelial cells following volutrauma and atelectrauma in mice and humanized in vitro models of the lung microenvironment. mTORC1 is also activated in lung tissue of mechanically ventilated patients with ARDS. Deletion of Tsc2, a negative regulator of mTORC1, in epithelial cells exacerbates physiologic lung dysfunction during mechanical ventilation. Conversely, treatment with rapamycin at the time mechanical ventilation is initiated prevents physiologic lung injury (i.e. decreased compliance) without altering lung inflammation or barrier permeability. mTORC1 inhibition mitigates physiologic lung injury by preventing surfactant dysfunction during mechanical ventilation. Our data demonstrate that in contrast to canonical mTORC1 activation under favorable growth conditions, activation of mTORC1 during mechanical ventilation exacerbates lung injury and inhibition of this pathway may be a novel therapeutic target to mitigate ventilator induced lung injury during ARDS.

molecular biology↗