In Nov 2023 I started my lab at the NIH (the Spatial Immunology Unit) as an Independent Research Scholar. We are combining spatial mapping of tissues with functional assays in organoid models to define the principles of immune programming during infection and inflammation with a focus on TB. (18/20)

A HUGE thank you my co-author, Alea Delmastro, who began as my undergrad mentee in 2018, adapted MIBI for NHP tissues (no small feat), and then became my co-lead on this study. Here we are celebrating after we stained the study cohort during the pandemic (a culmination of 3 years of work). (17/20)

Moral of the story? Granuloma hypoxia is associated with pathologic immune cell states, dysfunctional cellular organization of the granuloma, and a near-complete blockade of lymphocyte infiltration that would be required for a successful host response. (14/20)

Lastly, we confirmed that the same phenomenon of immunometabolic zonation is present in human pulmonary TB, underscoring the translational relevance of our findings. (13/20)

We also applied QUICHE (from the talented Jolene Ranek in the Angelo lab) to map the spatial networks of low- versus high-bacterial burden granulomas. With this analysis we found that hypoxia-associated spatial niches were over-represented in high-bacterial burden granulomas. (12/20)

One of the most notable findings from this analysis is that T cell infiltration in the myeloid core VERY sharply drops off with the onset of hypoxia, something that is very evident in poor-controlling granulomas. (11/20)

With this approach we generated a consensus map of what we termed granuloma radial immunotopography. With this mapping we can model how cell phenotypes, metabolic niches, and functional programs coordinate with each other over 2D space. (10/20)

We next asked how hypoxia influences global granuloma structure and function? To do this, we teamed up with Russ Butler’s group at AdventHealth to adapt a radial topography algorithm from the geographical information system (GIS) field. (9/20)

P.S. Stay tuned for more to come re: microGIS

This gave us the chance to dig even deeper into the cellular phenotypes we identified in our imaging data. We confirmed the tight coupling of macrophage metabolism and functional state with increasing evidence that hypoxia is associated with suppressive and pathologic immune responses. (8/20)

AND my newly formed lab at the NIH (more on this later…) had also just done our first spatial transcriptomic pilot study on some of the same granulomas we evaluated with multiplexed imaging. (7/20)

Luckily for us, @thebrysonlab.bsky.social had been working on a scRNAseq dataset of TB granuloma macrophages from the same model and infection timepoint (doi.org/10.1101/2024...). (6/20)

By integrating image-derived single cell data, annotations of these metabolic zones, and bacterial data, we found that macrophage phenotypes were tightly coupled to metabolic environment and that granulomas with high CFU (poor controllers) were enriched for hypoxia-associated macrophages. (5/20)

This dataset led us to revisit a long-known feature of granulomas: hypoxia. We observed that the myeloid core of granulomas partitioned into to two metabolically distinct zones: one defined by expression of the metabolic enzyme IDO1, and the other defined by sharply demarcated hypoxia. (4/20)

So back in 2018, we teamed up with @joanneflynn19.bsky.social, @joshmattila.bsky.social, et al at UPitt to spatially map granulomas from their NHP TB model. Because we knew the Mtb burden of each granuloma we could ask how spatial structure and function correspond with bacterial control (!!). (3/20)

Poppy insisting she come to the lab with me to grow some Meowcobacteria 🐈🧫