The present invention provides a method for modulating the complement cascade by depleting the plasma of the functional activity of complement proteins and thereby reducing or eliminating complement-mediated cell lysis. The invention provides a method for the therapeutic use of coat proteins and derivatives thereof from the Astroviradae family of viruses in the treatment of complement-mediated cell lysis and peptide mediators of inflammation. The invention provides a method for the therapeutic use of coat proteins and derivatives thereof from the Astroviradae family of viruses in the treatment of complement- mediated diseases. Methods are described herein where complement cascade, triggered by either the classical or alternative complement pathways, is prevented from effecting cell lysis and inflammation due to inhibition or depletion of one or more complement components in the serum following administration of astrovirus coat proteins or derivatives.
