Correction to: Nature Reviews Rheumatology (2021) https://doi.org/10.1038/s41584-020-00570-2, published online 01 February 2021.

In the originally published version of this article there was an error in Table 1. The phenotypes for immunomodulatory sub-lining fibroblasts and perivascular sub-lining fibroblasts were mistakenly swapped. In the row entitled “Sub-lining layer (immunomodulatory)”, the cell for “Marker genes (human)” has been corrected from “Negative (CD34); positive (CD90 and HLA-DRA)” to “Positive (CD90 and CD34)” and the cell for “Marker genes (mouse)” has been corrected from “Negative (Cd34); positive (Cd90)” to “Positive (Cd90 and Cd34)”. In the row entitled “Sub-lining layer (perivascular)”, the cell for “Marker genes (human)” has been corrected from “Positive (CD90 and CD34)” to “Negative (CD34); positive (CD90 and HLA-DRA) and the cell for “Marker genes (mouse)” has been corrected from “Positive (Cd90 and Cd34)” to “Negative (Cd34); positive (Cd90)”. This error has now been corrected in the HTML and PDF versions of the manuscript.