ICOSLG and rheumatoid arthritis: This demonstrated increased involvement of pathways linked to proliferation/expansion in early RA pDCs (p = 1 × 10−9, Z-score 2.17, genes involved: CSF1R, IFNAR1, IL6R, IL6ST, MAPK14) and CD1c+ DCs (p = 1.77 × 10−11, Z-score 2.76, genes involved BCL3, BTLA, CCR6, ICOSLG, IKZF1, IL6R, IRF8, TNF), although this was more marked in CD1c+ DCs where they also showed reduced apoptosis (p = 2.09 × 10−9, Z-score 2.27, genes involved: BCL3, CASP3, CASP8, CDKN1A, ICOSLG, IL6R, IRF8, MAPK14, TNF).