Thread by @mecfsskeptic

1) Interesting presentation by Anouk Slaghekke at the 2025 Berlin conference.

This Dutch team found that small blood vessels of patients with ME/CFS and Long Covid are clocked up with Collagen IV.

2) They zoomed in on the muscle capillaries, the tiny blood vessels that are so small that red blood cells need to move through them one by one.

3) The Dutch researchers found that the basement membrane was thicker in patients.

This is the supportive layer of proteins around the capillaries. It consists of proteins such as Collagen IV. Too much of it can stiffen the capillary walls.

4) They also found that the lumen space (the open space inside a blood vessel where blood actually flows) was reduced.

This may affect the perfusion of oxygen and nutrients to the muscle site.

5) Using electron microscopy the researchers could zoom in even further. This confirmed basement membrane thickening as well as membrane reduplications and signs of endothelial activation.

The endothelial cells were full of vesicles, excreting things into the circulation.

6) There was not a lot of overlap between patients and controls on these markers, so the researchers are exploring if they have potential as a biomarker or diagnostic test. They are looking for validation cohorts from other groups to see if they see similar things there.

7) The presentation by Ph.D researcher Anouk Slaghekke can be viewed on the website of the ME Research Foundation (@MECFSResearch).
events.mecfs-research.org/en/events/conf…

Her poster presentation is available here:
mecfs-research.org/wp-content/upl…

@MECFSResearch 8) There's more info about this research in the talk by group leader Rob Wüst:


Big thanks to Zaphereus and Anil for highlighting these findings to us.