We found that in RA synovium at disease onset two distinct clusters of FLS with specific tissue locations (sublining THY1posCOLA1pos and lining PGR4pos FLS respectively), that drive inflammation and damage (36), show the highest expression levels of p75NTR and of its co-receptor sortilin when compared to other synovial tissue cells. The gene discussed is NGFR; the disease is rheumatoid arthritis.