COL15A1 and arthritic joint disease: On the other hand, loss of functions per shrunk cluster during the progression of arthritis is highlighted in S1(Smoc2/Col15a1+) SFs, by, e.g., the disappearance of characteristic steroid biosynthetic process, BMP signaling, and chondrogenesis, while in S5(Ptx3/Notch3+) SFs, the regulation of several cytokine responses and tissue regeneration were also lost.