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Biology subjects

Eisinger, B.

Publications and source records attributed to Eisinger, B..

2 recordsLinked to original sources

Deep learning-guided selection of antibody therapies with enhanced resistance to current and prospective SARS-CoV-2 Omicron variants

Most COVID-19 antibody therapies rely on binding the SARS-CoV-2 receptor binding domain (RBD). However, heavily mutated variants such as Omicron and its sublineages, which are characterized by an ever increasing number of mutations in the RBD, have rendered prior antibody therapies ineffective, leaving no clinically approved antibody treatments for SARS-CoV-2. Therefore, the capacity of therapeutic antibody candidates to bind and neutralize current and prospective SARS-CoV-2 variants is a critical factor for drug development. Here, we present a deep learning-guided approach to identify antibodies with enhanced resistance to SARS-CoV-2 evolution. We apply deep mutational learning (DML), a machine learning-guided protein engineering method to interrogate a massive sequence space of combinatorial RBD mutations and predict their impact on angiotensin-converting enzyme 2 (ACE2) binding and antibody escape. A high mutational distance library was constructed based on the full-length RBD of Omicron BA.1, which was experimentally screened for binding to the ACE2 receptor or neutralizing antibodies, followed by deep sequencing. The resulting data was used to train ensemble deep learning models that could accurately predict binding or escape for a panel of therapeutic antibody candidates targeting diverse RBD epitopes. Furthermore, antibody breadth was assessed by predicting binding or escape to synthetic lineages that represent millions of sequences generated using in silico evolution, revealing combinations with complementary and enhanced resistance to viral evolution. This deep learning approach may enable the design of next-generation antibody therapies that remain effective against future SARS-CoV-2 variants.

immunology↗

Single-cell epigenomic reconstruction of developmental trajectories in human neural organoid systems from pluripotency

Human cell type diversity emerges through a highly regulated series of fate restrictions from pluripotent progenitors. Fate restriction is orchestrated in part through epigenetic modifications at genes and regulatory elements, however it has been difficult to study these mechanisms in humans. Here, we use organoid models of the human central nervous system and establish single-cell profiling of histone modifications (H3K27ac, H3K27me3, H3K4me3) in organoid cells over a time course to reconstruct epigenomic trajectories governing cell identity acquisition from human pluripotency. We capture transitions from pluripotency through neuroepithelium, to retinal and brain region specification, as well as differentiation from progenitors to neuronal and glial terminal states. We find that switching of repressive and activating epigenetic modifications can precede and predict decisions at each stage, providing a temporal census of gene regulatory elements and transcription factors that we characterize in a gene regulatory network underlying human cerebral fate acquisition. We use transcriptome and chromatin accessibility measurements in the same cell from a human developing brain to validate this regulatory mode in a primary tissue. We show that abolishing histone 3 lysine 27 trimethylation (H3K27me3) through inhibition of the polycomb group protein Embryonic Ectoderm Development (EED) at the neuroectoderm stage disrupts fate restriction and leads to aberrant cell fate acquisition, ultimately influencing cell type composition in brain organoids. Altogether, our single-cell genome wide map of histone modifications during human neural organoid development serves as a blueprint (https://episcape.ethz.ch) to explore human cell fate decisions in normal physiology and in neurodevelopmental disorders. More broadly, this approach can be used to study human epigenomic trajectory mechanisms in any human organoid system. SummaryUnguided neural organoids reveal widespread and dynamic switching of epigenetic modifications during development and recapitulate fate restriction from pluripotency to terminally differentiated cells of the human central nervous system.

developmental biology↗