Interestingly, blocking VEGF in inducible Alk1–/– mice partially reversed or blocked the development of AVMs induced by VEGF, LPS, or wounding (51, 55), in line with the well-documented effectiveness of the humanized anti-VEGF antibody bevacizumab in alleviating HHT symptoms (Table 1) (57, 58). Here, ACVRL1 is linked to hereditary hemorrhagic telangiectasia.