Many vaccines are made from whole killed or disabled versions of the disease-causing virus or bacterium. But in cases where this could be ineffective or too dangerous, protein fragments of the microbe might be used instead. However, these subunit vaccines aren’t a perfect solution, because they don’t always create a strong enough immune response. Delivering the fragments directly to the lymph nodes – where the immune response is generated – would really help, but getting them there has so far proved tricky. Now researchers have found a way to deliver subunit vaccines to lymph nodes by attaching fatty tails to the vaccine molecules. These fatty tails bind to blood protein albumin, allowing the vaccine to hitchhike to the lymph nodes. Pictured, stained neon green, is a hitchhiking subunit vaccine accumulating quickly in a lymph node. This discovery opens up possibilities for mobilising enhanced immunity to HIV and certain kinds of cancer.
Written by Cathleen O'Grady
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