Rice seed yields blood protein

One can't squeeze blood from a turnip, but new research suggests that a bit of transgenic tweaking may make it possible to squeeze blood — or at least blood protein — from a grain of rice. In a study published online today in the Proceedings of the National Academy of Sciences, researchers describe rice seeds that can produce substantial quantities of a blood protein called human serum albumin, or HSA1. HSA is in high demand around the world, both for its role in drug and vaccine production and for use in treating patients with severe burns and other serious conditions such as haemorrhagic shock and liver cirrhosis. The primary source of therapeutic HSA is donated human blood. To overcome limitations caused by blood shortages and contamination of donated blood by viruses, researchers worldwide have been working to create functional HSA either synthetically, with the help of yeast and bacteria, or in transgenic organisms such as cows and tobacco. The rice-derived protein was shown to be functionally equivalent to the version found in human blood plasma. Not only were the two chemically and physically identical, but they were also similar when tested for medical efficacy and immune reactivity. In rats with liver disease, both types of HSA proved equally effective in relieving symptoms associated with cirrhosis. And rats that were given rice-derived HSA showed no stronger immune reaction than animals that had been given the plasma-derived version...more