iiinova — where your digital self keeps evolving

Julia Belk @juliabelk.bsky.social · 29/09/2026

congrats Tessa!! this looks amazing

Reposted by Julia Belk

allen institute @alleninstitute.org · 22/09/2026

Meet the 2026 cohort of Next Generation Leaders. This program recognizes emerging early career researchers in bioscience and is designed to foster community, exchange of ideas, innovation, and collaboration to make a broad, transformational impact on the future of science.

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Julia Belk @juliabelk.bsky.social · 18/09/2026

although this study involved large datasets, it was 100% human science (no AI, unless you count the single cell clustering). also, this took us several years, and AI was much less capable even last year

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Reposted by Julia Belk

Open Box Science @openboxscience.bsky.social · 04/09/2026

Julia Belk's talk is now on Youtube! www.youtube.com/watch?v=uUOL... Microglia replacement during human aging @juliabelk.bsky.social Paper: Somatic mutations reveal the ontogeny of microglia in human aging (Nature 2026)

youtube.com

[Julia Belk] Microglia replacement during human aging

Speaker: Julia Belk Title: Microglia replacement during human aging Paper: Somatic mutations reveal the ontogeny of microglia in human aging (Nature 2026)

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Reposted by Julia Belk

Eric Topol @erictopol.bsky.social · 13/08/2026

Our understanding how our brain ages and why our memory begins to slip around age 50 have been completely revamped through 2 new landmark studies involving the microglia, the brain immune cells erictopol.substack.com/p/why-our-me...

erictopol.substack.com

Why Our Memory Slips After Age 50

Landmark independent studies challenge longstanding dogma for brain aging

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Julia Belk @juliabelk.bsky.social · 30/07/2026

Despite this track record, Sidd and Howard were unfazed, and I had one more idea in mind. That idea was PACT, which worked because it is compatible with the archival human brain specimens that are abundant in tissue banks, and you can read more about in the paper. 9/

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Julia Belk @juliabelk.bsky.social · 30/07/2026

On a more personal note, I am very grateful to Sidd Jaiswal, Howard Chang, and many collaborators for their patience over the years. PACT wasn't the first idea I had; after a few years of work, I had racked up several false starts, no data, and a humongous sequencing bill. 8/

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Julia Belk @juliabelk.bsky.social · 30/07/2026

Additionally, it will be essential to revisit the models being used to study age-associated diseases. For example, yolk sac microglia (extensively characterized in mice) may not be the most relevant cell type in human Alzheimer’s disease. 7/

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Julia Belk @juliabelk.bsky.social · 30/07/2026

We hope that these findings will enable new immunotherapies for human neuroscience, where peripheral immune cells can be engineered as delivery vehicles or as cell therapies to treat or prevent a wide range of neurological disorders. 6/

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Julia Belk @juliabelk.bsky.social · 30/07/2026

Serendipitously, Nathan Zemke, Bing Ren, and Joe Ecker discovered the same phenomenon using a different approach: single cell methylation. Collectively, these data show that the replacement of yolk sac microglia by monocytes starts in middle age and is ~complete by age ~80. 5/

science.org

Epigenetic and 3D genome reprogramming during the aging of the human hippocampus

Changes in gene expression have been observed in the aging human brain, but our understanding of the underlying regulatory mechanisms remains limited. To unravel these complexities, we analyzed single...

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Julia Belk @juliabelk.bsky.social · 30/07/2026

We find that peripheral immune cells make major contributions to the microglial pool in aged individuals, and some of these cells also may play a protective role in the context of Alzheimer's disease. 4/

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Julia Belk @juliabelk.bsky.social · 30/07/2026

To lineage trace human microglia, we developed a new approach (PACT). PACT uses the somatic mutations that accumulate in the nuclear genome during aging to identify expanded clones in the blood and track these clones into the brain. 3/

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Julia Belk @juliabelk.bsky.social · 30/07/2026

This discovery required new technologies; although many approaches can identify microglia (brain-resident immune cells), it has not been possible to lineage trace these cells in humans to test whether they stay inside the brain throughout life or not. 2/

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Julia Belk @juliabelk.bsky.social · 30/07/2026

Gaining therapeutic access to the human brain is one of the biggest unsolved problems in biomedical science. Today @nature.com, we uncover a massive influx of immune cells into the human brain during aging, revealing that the brain is more accessible than previously thought. 1/

nature.com

Somatic mutations reveal the ontogeny of microglia in human aging - Nature

Nature - Somatic mutations reveal the ontogeny of microglia in human aging

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Reposted by Julia Belk

Katherine King MD PhD @thekinglab.bsky.social · 02/07/2025

And here it is! Our study in clonal hematopoiesis and Alzheimer’s disease — product of 5 years’ gestation. urldefense.proofpoint.com/v2/url?u=htt...

urldefense.proofpoint.com

ScienceDirect.com | Science, health and medical journals, full text articles and books.

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Julia Belk @juliabelk.bsky.social · 18/04/2025

A lot of fun teaming up with Hsin and Howard on this, with key contributions from @ruochiz.bsky.social, @zchiang.bsky.social, and @jbuenrostro.bsky.social on the tech dev and @mattjones.bsky.social, Natasha Weiser, and Paul Mischel on the ecDNA analysis. (5/5)

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Julia Belk @juliabelk.bsky.social · 18/04/2025

We also apply SPACE-seq to an archived glioblastoma sample, showing that SPACE-seq works well with clinical samples and can detect extrachromosomal DNA amplifications and somatic mutations. (4/5)

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Julia Belk @juliabelk.bsky.social · 18/04/2025

Mitochondrial DNA is captured as well, enabling mtscATAC (a lineage tracing technique previously developed by @caleblareau.bsky.social, @leifludwig.bsky.social, and @bloodgenes.bsky.social) to be applied spatially. (3/5)

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Julia Belk @juliabelk.bsky.social · 18/04/2025

The main idea here is that by tagmenting tissue sections with polyA-tailed adapters, instead of the standard ATAC-seq adapters, we can use spatial transcriptomics slides from @10xgenomics.bsky.social to capture both ATAC and RNA data with spatial resolution. (2/5)

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Reposted by Julia Belk

HHMI @hhmi-science.bsky.social · 08/01/2025

Today we're thrilled to announce our 2024 #HannaGrayFellows! Please join us in welcoming and celebrating these outstanding early career scientists!

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