In patients with CCM, the BBB is impaired (Clatterbuck, 2001; Mikati et al., 2015), as reported here in this murine Pdcd10-depletion model, where there was significant increase in vascular permeability to endogenous immunoglobulins (Figure 2F, cerebellum; Figure 2—figure supplement 1A, cerebrum). Here, PDCD10 is linked to cerebral cavernous malformation.