On the nature of degenerative diseases and possible therapy: a hypothesis

The hypothesis of a pathway common to the degenerative disease, amenable to particular therapies, is discussed. C3D, formed by activation of the complement cascade, markedly amplifies the synthesis of immunoglobulin, that may increase microglial activation and thus induce neuronal damage and death. If, indeed, the formation of C3D and activated microgliocytes are critical steps in the degenerative pathway, "combination therapy" utilising immunomodulatory and immunosuppressive preparations, the former to inhibit the antigen presenting (dendritic) cell and the latter to inhibit lymphocyte activation, may ameliorate the degenerative process.