Moreover, the unexpected discovery that the receptor for C1q, gC1qR––expressed on endothelial cells––is also one of the key proteins (the others being cytokeratin-1 [CK-1] and urokinase-type plasminogen activator receptor [uPAR]) that facilitates the assembly and activation of the kinin-generating pathway has also provided a novel platform for understanding the disease hereditary angioedema (HAE). Here, KRT1 is linked to hereditary angioedema.