By Science Daily
Rheumatoid arthritis is a condition that causes painful inflammation of several joints in the body. The joint capsule becomes swollen, and the disease can also destroy cartilage and bone as it progresses. Rheumatoid arthritis affects 0.5% to 1% of the world’s population. Up to this point, doctors have used various drugs to slow or stop the progression of the disease. But now, ETH Zurich researchers have developed a therapy that takes the treatment of rheumatoid arthritis in mice to a new level: after receiving the medication, researchers consider the animals to be fully cured.
The drug is a biotechnologically produced active substance consisting of two fused components. One component is the body’s own immune messenger interleukin 4 (IL-4); previous studies have shown that this messenger protects mice with rheumatoid arthritis against cartilage and bone damage. ETH scientists have coupled an antibody to IL-4 that, based on the key-lock principle, binds to a form of a protein that is found only in inflamed tissue in certain diseases (and in tumour tissue).
Localized drug delivery
“As a result of combination with the antibody, IL-4 reaches the site of the disease when the fusion molecule is injected into the body,” says pharmacist Teresa Hemmerle, who has just completed her dissertation in the group of Dario Neri, a professor at the Institute of Pharmaceutical Sciences. Together with Fabia Doll, also a PhD pharmacist at ETH, she is the lead author of the study. “It allows us to concentrate the active substance at the site of the disease. The concentration in the rest of the body is minimal, which reduces side-effects,” she says.