PPIB and systemic lupus erythematosus: This modulation has functional consequences, as the stimulation of HUVEC with the supernatant of SLE monocytes stimulated with IFN-β (conditioned media -CMIFN-β-) reduced the activation of Tie2 and induced a defective angiogenesis, compared to non-stimulated cells, or stimulated with the conditioned media of unstimulated monocytes (Supplementary, Figure 6).