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Biology subjects

Gubbels, L.

Publications and source records attributed to Gubbels, L..

3 recordsLinked to original sources

Macrophages Mediate Antiviral Immunity and Repair of Type 2 Alveolar Epithelial Cells in a Human Stem Cell Model

The lung alveoli are constantly exposed to inhaled pathogens and inorganic hazards, relying on robust defence mechanisms to maintain homeostasis. Alveolar macrophages and type 2 alveolar epithelial cells (AT2s) collaborate to orchestrate protection. Compromised defence can dysregulate immunity and repair, leading to acute and chronic respiratory diseases. To better understand these processes and drive therapeutic discovery, human model systems that capture key cell interactions are essential. Here, we develop the first induced pluripotent stem cell (iPSC)-derived platform that integrates AT2 cells and macrophages in an air-liquid interface culture. Coculture enhanced AT2-specific gene expression and lipid synthesis, while macrophages actively phagocytosed AT2-derived surfactant. iPSC-derived AT2s supported macrophage survival by producing M-CSF and coculture promoted an alveolar macrophage-like phenotype. Additionally, during respiratory infection macrophages played a crucial role in modulating proinflammatory signalling, enhancing antiviral immunity, and restricting viral replication. Furthermore, we identify a role for iPSC-derived macrophages in epithelial repair, with VEGF signalling to macrophages increasing epithelial permeability. We present an iPSC-derived air-interface platform to study AT2-macrophage interactions in homeostasis, infection, and repair, providing insights into their potential roles in the initiation and progression of respiratory diseases.

cell biology↗

Antibody responses against bacterial glycans affinity mature and diversify in germinal centers.

Anti-carbohydrate antibodies (Abs) play crucial roles in pathogen control, but their generation remains poorly understood. By studying responses to Streptococcus pyogenes in humans, we reveal that the glycan-targeted response shifts from IgM towards IgG and IgA memory with age and antigen exposure across blood, spleen, and tonsils. Both natural colonization and controlled human infection with S. pyogenes increased class-switched B cells, with evidence of within-clone switching. Glycan-specific B cells readily participated in germinal center (GC) responses and showed robust somatic hypermutation despite a molecular signature consistent with receiving reduced T cell help. We conclude that mucosal pathogen encounters elicit glycan responses that class-switch, evolve and diversify through the GC. These findings reveal how age and infection history can influence the quality, quantity, and isotype use of glycan-specific B cells, with implications for the design and schedule of glycan-containing vaccines.

immunology↗

More cells, more doublets in highly multiplexed single-cell data

Withdrawal statementThe authors have withdrawn this manuscript. In our initial submission of this paper, we proposed a combinatoric model for the probability of finding doublets in sample-barcoded single-cell RNA-sequencing data. This model predicts a doublet rate higher than the rate included in the documentation for the 10X Flex protocol. This was motivated by our use of doublet-finding software, scDblFinder, on experimental data using the Flex protocol, which identified several times more doublets than we expected based on the documentation. Our original model produced better agreement with the results of scDblFinder in 9 of our own data sets as well as one public dataset made available by 10X. During revisions, however, we performed Monte Carlo simulations of doublet formation that were inconsistent with the results of our model, and much closer to the predictions from the documentation. This prompted us to reanalyse the assumptions of our model. A longer version of this withdrawal statement that explains in detail the errors in the model and includes updated figures is available at https://github.com/Oshlack/flex-doublets, but in brief, our initial assumptions over-predicted the doublet fraction, and our revised model is now consistent with both the Monte Carlo simulations and the predictions from the Flex documentation. We therefore speculate that the unexpectedly high doublet fractions observed in the experimental data might be due to some combination of experimental conditions and software performance. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please ontact the corresponding author.

bioinformatics↗