A study by Dorothy P. Schafer, PhD, and Travis E. Faust, PhD, in Cell explains how cell types in the brain communicate in response to changes in sensory input to remodel synapses: direc.to/nJHH

Alzheimer’s and ALS patients have synaptic damage.

@travisfaust.bsky.social @cp-cell.bsky.social

Thank you Ciaran!! 😄

Thanks so much! Dori has been a fantastic mentor - I’m glad you were able to connect with her 😊

Ha, fair takeaway 🙂. Mice use whiskers a bit like we use our fingertips — trimming them helps us study how brain connections change when inputs go quiet. If you’re curious, here’s a short public talk I gave that starts broad and then dives into this work: youtu.be/Gb22qhBVfOA?...

Thanks Ethan!!

Thanks so much! Really appreciate it 🙏

Thanks Lindsay! We're really excited to see where this work leads. It's great to see the growing interest in glia-glia interactions.

Thanks Lewis!

🙏 Thanks to my mentor Dorothy Schafer, collaborators @caglaeroglu.bsky.social, @pinar-ayata.bsky.social, and Anne Schaefer, and all my co-authors.

Proud to do this work at @umasschan.bsky.social.

💡 Excited to see where glial biology goes next!

🔮 Open questions ahead:

When do microglia release Wnt?

What happens when astrocytes change how much they touch synapses in development, sleep, aging, or disease?

Does less astrocyte contact generally make synapses easier for microglia to remove?

How do microglia remove less-contacted synapses?

We show that astrocytic Wnt signaling is also seen in:
💤 Sleep
⏳ Aging
⚡ Seizures
🧠 Alzheimer’s disease

In these contexts, changes in astrocyte morphology & synapse loss have been reported, suggesting this pathway may be shared across brain states & disorders.

To reveal this pathway we used:
🧠 A defined cortical circuit model of activity-driven synapse loss
🔍 Expansion microscopy to map astrocyte–synapse contacts
🧬 TRAP-Seq + MERFISH to identify microglial Wnts
✂️ Cell type–specific knockouts to test signaling

After sensory deprivation we found:
⚡ Neurons signal to microglia via CX3CL1–CX3CR1
🔁 Microglia release Wnts, causing astrocytes to reduce synaptic contact
🧹 Reduced astrocyte–synapse contact allows microglia to remove synapses

(Our prior work on CX3CL1/CX3CR1: doi.org/10.1038/s415...)

🧩Both microglia and astrocytes can remove synapses.

But their respective roles — and whether they act independently, redundantly, or in coordination — has been unclear. How do neurons, microglia, and astrocytes work together during synapse remodeling?

Thrilled to share our new paper @cp-cell.bsky.social:
“Microglia–astrocyte crosstalk regulates synapse remodeling via Wnt signaling.”

This work demonstrates the necessity of glia–glia communication and coordination during synapse remodeling.

🔗 www.cell.com/cell/fulltex...

Faust et al., Cell 2025

Faust, Brenner et al. @harvardmed.bsky.social show that type I IFN signaling contributes to #arthritis pathogenesis in obesity through activation and expansion of CD8 T cells in visceral adipose tissue and synovium. rupress.org/jem/article/...

#Autoimmunity

Thrilled to announce that my lab is now open at Ohio State! We study astrocytes as gene therapy targets for brain repair after ischemic stroke and in vascular dementia, developing new viral tools along the way. If you're interesting in joining or collaborating, please reach out!
gleichmanlab.com

Another option is rabbit anti-SOX9 (1:500; ab185966 Abcam). Example images and protocol in here: www.biorxiv.org/content/10.1...

go.bsky.app/Lyzro3M

!WELCOME!

thought we might need a starter pack for all those coming over from the birdhouse - here's a GliaSky list.

apologies for missing many of you - please do reply to get added

and remember to repost so the newbies can find us!