In this study, we systematically evaluated four mouse models of SVD (hypertensive BPH mice, Col4a1 mutants, Notch3 mutants and mice lacking the HtrA serine protease Htra1−/−) for the infiltration of peripheral immune cells after postmortem MRI of the brain and for the activation of resident immune cell populations and blood–brain barrier (BBB) integrity. This evidence concerns the gene HTRA1 and snowflake vitreoretinal degeneration.