Establishing a human lymphoid organoid and explant hub to replace animal models in immunology research

The award will allow Pablo to purchase equipment, consumables and training materials to establish a high throughput facility to generate lymphoid organoids prepared from human tonsil and spleen tissue for immunology studies a field that relies heavily on animal models. The facility will provide lymphoid organoids for researchers at the University of Oxford and across the UK.

This award was made as part of the 2024 non-animal methods infrastructure grants supported with funding from the Department for Science, Innovation and Technology (DSIT).

Mice have long been the preferred model for studying multisystemic immunity. However, accumulated evidence shows that mouse immunology poorly replicates the genetic, biochemical, and physical diversity of humans. The recent development of lymphoid organoids from tonsils and spleens by Professor Mark Davis's group demonstrates the scientific benefits and predictive power of non-animal, primary human lymphoid organoids. Despite these advantages, broad adoption of these organoids remains challenging due to limited access to fresh human tissue samples and protocols for their use.

Our lab has successfully adopted the tonsil organoid technology from Mark Davis's lab and developed a second method for investigating lymphocyte self-organization into ex vivo follicles. Davis's approach uses BAFF and attenuated influenza virus to trigger adaptive immune responses. In contrast, our method employs synthetic T-cell trans-synaptic vesicles (stSV) carrying CD40L to mimic follicular helper T cells (TFH)-derived and B-cell activating signals. These stSVs accelerate lymphocyte organization into follicle-like structures, supporting native antigen presentation events and germinal center reactions. Our semi-synthetic system can be primed with recombinant antigens and other growth factors, enabling a wide variety of experimental designs. For instance, we have achieved excellent genome editing efficiency in primary tonsillar T-cells, allowing us to conduct numerous genetic ablation experiments to assess the function of human proteins in cell-cell communication. This approach has replaced the need for genetically modified mouse models, with significant potential to further reduce animal model use.

We aim to establish a hub to foster collaboration and promote the adoption and development of lymphoid organoid approaches. This will include acquiring essential equipment, consumables, and resources for teaching, validation, and benchmarking methods to meet various experimental needs. We seek to remove barriers to proof-of-principle experiments by providing access to instruments, tissues, recombinant materials, protocols, and hands-on training. Our goal is to create a comprehensive methodological framework and support its adoption in multiple areas of immunology research. We have identified several mechanisms to generate data and resources demonstrating the usefulness of lymphoid clusters and organoids for studying immunology across various time and length scales. By the end of the project, we aim to develop web resources to facilitate the transparent exchange of our knowledge base, ultimately impacting different departments, sectors, and the international community.