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Biology subjects

Morrow, A. L.

Publications and source records attributed to Morrow, A. L..

3 recordsLinked to original sources

Prenatal SARS-CoV-2 infection alters postpartum human milk-derived extracellular vesicles

Human milk-derived extracellular vesicles (HMEVs) are crucial functional components in breast milk, contributing to infant health and development. Maternal conditions could affect HMEV cargos; however, the impact of SARS-CoV-2 infection on HMEVs remains unknown. This study evaluated the influence of SARS-CoV-2 infection during pregnancy on postpartum HMEV molecules. Milk samples (9 prenatal SARS-CoV-2 vs. 9 controls) were retrieved from the IMPRINT birth cohort. After defatting and casein micelle disaggregation, 1 mL milk was subjected to a sequential process of centrifugation, ultrafiltration, and qEV-size exclusion chromatography. Particle and protein characterizations were performed following the MISEV2018 guidelines. EV lysates were analyzed through proteomics and miRNA sequencing, while the intact EVs were biotinylated for surfaceomic analysis. Multi-Omics was employed to predict HMEV functions associated with prenatal SARS-CoV-2 infection. Demographic data between the prenatal SARS-CoV-2 and control groups were similar. The median duration from maternal SARS-CoV-2 test positivity to milk collection was 3 months (range: 1-6 months). Transmission electron microscopy showed the cup-shaped nanoparticles. Nanoparticle tracking analysis demonstrated particle diameters of <200 nm and yields of >1e11 particles from 1 mL milk. Western immunoblots detected ALIX, CD9 and HSP70, supporting the presence of HMEVs in the isolates. Thousands of HMEV cargos and hundreds of surface proteins were identified and compared. Multi-Omics predicted that mothers with prenatal SARS-CoV-2 infection produced HMEVs with enhanced functionalities involving metabolic reprogramming and mucosal tissue development, while mitigating inflammation and lower EV transmigration potential. Our findings suggest that SARS-CoV-2 infection during pregnancy boosts mucosal site-specific functions of HMEVs, potentially protecting infants against viral infections. Further prospective studies should be pursued to reevaluate the short- and long-term benefits of breastfeeding in the post-COVID era.

systems biology↗

Red blood cell-derived extracellular vesicles with miR-204 mimic loading for pediatric neuroblastoma treatment

Neuroblastoma (NB) is the most common extracranial solid tumor in pediatric population with a high degree of heterogeneity in clinical outcomes, ranging from spontaneous remission to rapid progression and death. Upregulation of a tumor suppressor miR-204 in patient-derived neuroblastoma tumors was associated with good prognosis independent of known risk factors. While miR-204 is recognized as a therapeutic candidate, its delivery was unavailable. This study aimed to develop red blood cell-derived extracellular vesicles (RBC-EVs) as the miR-204 carrier and evaluate the inhibitory activity against neuroblastoma cell lines and spheroids. MiR-204 mimics were loaded into RBC-EVs (RBC-EVmiR-204) by electroporation with the optimized parameters of 250 V, 20 ms, 10 pulsing times. RBC-EVmiR-204, but not the native RBC-EVs, could inhibit cell viability, migration and spheroid formation and growth of MYCN-amp and MYCN non-amplification (MYCN-NA) NB cells, even though the suppressive effects were more preferable in MYCN-amp NB. For the mechanistic insight, SWATH-proteomics suggested that RBC-EVmiR-204 induced dysregulation of ribosomal proteins and alterations in RNA metabolism, leading to inhibiting neuroblastoma progression. This study developed RBC-EVmiR-204 as an alternative/adjunct therapy of pediatric neuroblastoma. The therapeutic efficacy of RBC-EVmiR-204 should be further investigated in preclinical models and clinical studies.

bioengineering↗

Accelerating Drug Discovery and Repurposingby Combining Transcriptional Signature Connectivity with Docking

The development of targeted treatment options for precision medicine is hampered by a slow and costly process of drug screening. While small molecule docking simulations are often applied in conjunction with cheminformatic methods to reduce the number of candidate molecules to be tested experimentally, the current approaches suffer from high false positive rates and are computationally expensive. Here, we present a novel in silico approach for drug discovery and repurposing, dubbed connectivity enhanced Structure Activity Relationship (ceSAR) that improves on current methods by combining docking and virtual screening approaches with pharmacogenomics and transcriptional signature connectivity analysis. ceSAR builds on the landmark LINCS library of transcriptional signatures of over 20,000 drug-like molecules and ~5,000 gene knock-downs (KDs) to connect small molecules and their potential targets. For a set of candidate molecules and specific target gene, candidate molecules are first ranked by chemical similarity to their concordant LINCS analogs that share signature similarity with a knock-down of the target gene. An efficient method for chemical similarity search, optimized for sparse binary fingerprints of chemical moieties, is used to enable fast searches for large libraries of small molecules. A small subset of candidate compounds identified in the first step is then re-scored by combining signature connectivity with docking simulations. On a set of 20 DUD-E benchmark targets with LINCS KDs, the consensus approach reduces significantly false positive rates, improving the median precision 3-fold over docking methods at the extreme library reduction. We conclude that signature connectivity and docking provide complementary signals, offering an avenue to improve the accuracy of virtual screening while reducing run times by multiple orders of magnitude.

bioinformatics↗