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Zoodsma, M.

Publications and source records attributed to Zoodsma, M..

2 recordsLinked to original sources

CellDemux: coherent genetic demultiplexing in single-cell and single-nuclei experiments.

Multiplexed single-cell experiment designs are superior in terms of reduced batch effects, increased cost-effectiveness, throughput and statistical power. However, current computational strategies using genetics to demultiplex single-cell (sc) libraries are limited when applied to single-nuclei (sn) sequencing data (e.g., snATAC-seq and snMultiome). Here, we present CellDemux: a computational framework for genetic demultiplexing within and across data modalities, including single-cell, single-nuclei and paired snMultiome measurements. CellDemux uses a consensus approach, leveraging modality-specific tools to robustly identify non-empty oil droplets and singlets, which are subsequently demultiplexed to donors. Notable, CellDemux demonstrates good performance in demultiplexing snMultiome data and is generalizable to single modalities, i.e. snATAC-seq and sc/snRNA-seq libraries. We benchmark CellDemux on 187 genetically multiplexed libraries from 800 samples (scRNA-seq, snATAC-seq, CITE-seq and snMultiome), confidently identifying and assigning cells to 88% of donors. In paired snMultiome libraries, CellDemux achieves consistent demultiplexing across data modalities. Moreover, analysis of 38 snATAC libraries from 149 samples shows that CellDemux retains more genetically demultiplexed nuclei for downstream analyses compared to existing methods. In summary, CellDemux is a modular and robust framework that deconvolves donors from genetically multiplexed single-cell and single-nuclei RNA/ATAC/Multiome libraries.

genomics↗

Differences in anti-viral immune responses in individuals of Indian and European origin: relevance for the COVID-19 pandemic

During the COVID-19 pandemic, large differences in susceptibility and mortality due to SARS-CoV-2 infection have been reported between populations in Europe and South Asia. While both host and environmental factors (including BCG vaccination) have been proposed to explain this, the potential biological substrate of these differences is unknown. We purified peripheral blood mononuclear cells from individuals living in India and the Netherlands at baseline and 10-12 weeks after BCG vaccination. We compared chromatin accessibility between the two populations at baseline, as well as gene transcription profiles and cytokine production capacities upon viral stimulation with influenza and SARS-CoV-2. The chromatin accessibility of genes important for adaptive immunity was higher in Indians compared to Europeans, while the latter had more accessible chromatin regions in genes of the innate immune system. At the transcriptional level, we observed that Indian volunteers displayed a more tolerant immune response to viral stimulation, in contrast to a more exaggerated response in Europeans. BCG vaccination strengthened the tolerance program in Indians, but not in Europeans. These differences may partly explain the different impact of COVID-19 on the two populations.

immunology↗