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Gallego, P.

Publications and source records attributed to Gallego, P..

3 recordsLinked to original sources

Host factor PLAC8 is required for pancreas infection by SARS-CoV-2

BackgroundAlthough COVID-19 initially caused great concern about respiratory symptoms, mounting evidence shows that also the pancreas is productively infected by SARS-CoV-2. However, the severity of pancreatic SARS-CoV-2 infection and its pathophysiology are still under debate. Here we investigated the consequences of SARS-CoV-2 pancreatic infection and the role of the host factor Placenta-associated protein (PLAC8) MethodsWe analyzed plasma levels of pancreatic enzymes and inflammatory markers in a retrospective cohort study of 120 COVID-19 patients distributed in 3 severity-stratified groups. We studied the expression of SARS-CoV-2 and PLAC8 in the pancreas of deceased COVID-19 patients as well as in non-infected donors. We performed infection experiments in PLAC8 knock-out PDAC cell lines with full SARS-CoV-2 virus. ResultsWe found that analysis of circulating pancreatic enzymes aided the stratification of patients according to COVID-19 severity and predict outcomes. Interestingly, we found an association between PLAC8 expression and SARS-CoV-2 infection in postmortem analysis of COVID-19 patients. Using full SARS-CoV-2 infectious virus inoculum from Wuhan-1 and BA.1 strains, we demonstrated that PLAC8 is necessary for productive infection of PDAC cell lines. Finally, we observed an overlap between PLAC8 and SARS-CoV-2 immunoreactivities of the pancreas of deceased patients. ConclusionOur data indicate the human pancreas as a SARS-CoV-2 target with plausible signs of injury and demonstrate that the host factor PLAC8 is required for SARS-CoV-2 pancreatic infection, thus defining new target opportunities for COVID-19-associated pancreatic pathogenesis. Plain language summaryPrevious studies have shown that the pancreas is infected by SARS-CoV-2. However, none of these studies have described measurable pancreatic damage associated to COVID-19 severity and the pathogenesis of pancreatic SARS-CoV-2 infection remains largely unknown. Novel host factors have been proposed for SARS-CoV-2 infection of mainly the airway epithelium, none of them studied in the pancreas. Our study shows clinically relevant pancreatic damage associated with SARS-CoV-2 infiltration and assesses the predictive potential of circulating pancreatic enzymes to stratify patients according to COVID-19 severity and predict clinical outcomes in a cohort of 120 patients. Our data show that host factor Placenta-associated protein 8 (PLAC8) expression is linked to SARS-CoV-2 infection in postmortem analysis of COVID-19 patients and functionally demonstrated the full requirement of PLAC8 for SARS-CoV-2 pancreatic infection and viral replication. Our data confirm the human pancreas as a SARS-CoV-2 target with signs of injury unveiling the measurement of pancreatic enzymes for prognosis value and demonstrating that host factor PLAC8 is required for SARS-CoV-2 pancreatic infection defining new stratification and target opportunities for COVID-19-associated pancreatic pathogenesis.

cell biology↗

Non-overlapping requirements of ASNA-1 function for insulin secretion, cisplatin resilience, and growth revealed by genetic analysis of point mutants in C. elegans

ASNA1 plays an essential role in cisplatin chemotherapy response, type 2 diabetes, and heart disease. It is also an important biomarker in the treatment response of many diseases. Biochemically, ASNA1 has two mutually exclusive redox modulated roles: a tail-anchored protein (TAP) targeting function in the reduced state and a holdase/chaperone function in the oxidized state. Assigning biochemical roles of ASNA-1 to biomedical functions is crucial for successful therapy development. Our previous work showed the relevance of the C. elegans ASNA-1 homolog in modeling cisplatin response and insulin secretion. Here we analyzed two-point mutants in highly conserved residues in C. elegans ASNA-1 and identified their importance in separating cisplatin response from its roles in insulin secretion. Further, using targeted depletion we showed asna-1 tissue requirements for C. elegans growth and development. We concluded that, targeting single residues in ASNA-1 affecting Switch I/II domain function, in comparison to complete knockdown counteracted cisplatin resistance without jeopardizing other important biological functions. Taken together, our study shows that effects on health caused by ASNA1 mutations can have different biochemical bases.

cell biology↗

Neuroinflammation in the normal appearing white matter of multiple sclerosis brain causes abnormalities at the node of Ranvier

Changes to the structure of nodes of Ranvier in the normal-appearing white matter (NAWM) of MS brains are associated with chronic inflammation. We show that the paranodal domains in MS NAWM are longer on average than control, with Kv1.2 channels dislocated into the paranode. These pathological features are reproduced in a model of chronic meningeal inflammation generated by the injection of lentiviral vectors for the lymphotoxin- (LT) and interferon-{gamma} (IFN{gamma}) genes. We show that tumour necrosis factor (TNF), IFN{gamma} and glutamate can provoke paranodal elongation in cerebellar slice cultures, which could be reversed by an NMDA blocker. When these changes were inserted into a computational model to simulate axonal conduction, a rapid decrease in velocity was observed, reaching conduction failure in small diameter axons. We suggest that glial cells activated by proinflammatory cytokines can produce high levels of glutamate, which triggers paranodal pathology, contributing to axonal damage and conduction deficits.

neuroscience↗