Complement and Kidney Disease

The understanding how complement relates to glomerular diseases
has evolved considerably during the last years. Substantial
evidence has accumulated that explain how a defective or
deregulated complement system results in kidney diseases. The
combination and close interaction of basic research with clinical
medicine has demonstrated an important role of complement effector
and regulatory proteins in pathological settings of the kidney.
A large panel of distinct human kidney diseases such as hemolytic
uremic syndrome (HUS), membrano proliferative glomerulonephritis
(MPGN), systemic lupus erythematosus (SLE) and in ischemic
reperfusions injury and transplantation are caused by defective
complement control. Genetic analyses have identified mutations in
complement regulators that are associated with these diseases.
Mutations have been identified in the fluid phase alternative
pathway regulator Factor H and the membrane regulator Membrane
Cofactor Protein MCP (CD46). The functional characterization of the
mutant proteins allows to define the pathophysiological events on a
molecular level. These new concepts and data on disease mechanisms
already allowed to establish new diagnostic and novel promising
therapeutic approaches for several human kidney diseases.