Hemolytic uremic syndrome: how do factor H mutants mediate endothelial damage?

Hemolytic uremic syndrome is characterized by microangiopathic hemolytic anemia, thrombocytopenia and acute renal failure. Data from recent genetic analyses reveal a clear association between the complement regulator factor H and the atypical form of this fatal human disease. The clustering of the identified mutations in the C-terminus of factor H identifies a "hot spot" that is central to the pathogenesis of the disease. What are the possible biological and functional consequences of the identified mutations for the disease process and mechanisms of disease progression?