In vivo treatment of Heymann's Nephritis using a cytotoxic protein-toxin conjugate

Fucoidan inhibits the development of proteinuria in active Heymann nephritis

Fucoidan, the sulphated polysaccharide extracted from brown seaweed, has various biological activities. The effect of fucoidan on the formation of proteinuria and renal functions in active Heymann nephritis was investigated in this study. Active Heymann nephritis was induced by administering brush border protein of rat proximal uriniferous tubules (FX1A). Fucoidan was administered by oral intubation to Heymann nephritis rats at three doses (50, 100 and 200 mg/kg) once daily for 4 weeks. The elevated urinary protein excretion and plasma creatinine due to the induction of Heymann nephritis were significantly reduced by fucoidan at doses of 100 and 200 mg/kg. The results indicated that fucoidan has a renoprotective effect on active Heymann nephritis and is a promising therapeutic agent for nephritis.

Are immunoconjugates useful for therapy with autoimmune diseases?

Immunoconjugates or immunotoxins (ITs) are targeting molecules which consist of a monoclonal antibody together with a toxin--thereby they can selectively kill target cells in a highly efficient manner. The use of ITs as a drug targeting approach is one of the most attractive research fields for tumor therapy; however, the study of ITs for the treatment of autoimmune diseases has been given little attention until recently. It has been shown that ITs could help alleviate the symptoms of myasthenia gravis and rheumatoid arthritis in animal models. In the last 3 yr ITs have been used in clinical trials (phase I and phase II) for the treatment of various autoimmune diseases including rheumatoid arthritis, systemic lupus erythematosus, insulin-dependent diabetes mellitus and psoriasis. This article reviews the main progress on the application of ITs for the therapies of autoimmune diseases. The preliminary results suggest the future may hold some promise, but side effects, in addition to there being no convincing efficacy, remain unresolved.

Cell surface receptor directed targeting of toxin to human malaria parasite, Plasmodium falciparum

Gelonin (a toxin and type II ribosome inactivating protein) when linked to human transferrin can be targeted to Plasmodium falciparum. The transferrin toxin conjugate is significantly toxic to parasite growth and is 25 times more potent than toxin alone in inhibiting parasite protein synthesis. The mechanism of its entry into the intraerythrocytic parasite is discussed.