PDCD1LG2 and systemic sclerosis: We analysed the characteristics of pro-phagocytic hMDMs in SSc patients by examining phenotypic markers for classically activated M(LPS) and alternatively-activated M(IL-4) macrophages (CD38, CD40, CD86, CD163, CD206, PD-L2, PD-L1) (Supplementary Fig. S3A, available at Rheumatology online).