Scientists have developed a drug development technique that could lead to a new class of low cost medicines.
A research team led by David Fairlie and Dr Robert Reid from the Institute for Molecular Bioscience designed a technique that can reduce large proteins to small molecules suitable for use as medicine.
The result was complement protein C3a, a smaller, more affordable version of a powerful human inflammatory protein. C3a costs thousands of dollars per milligram to manufacture and degrades quickly in blood, making it too expensive and unstable to be readily used in medicines.
The research team designed a small molecule that retains the same potent properties of C3a, but is much cheaper and more stable for use in drug development.
"Despite the importance of proteins to nearly every function in the body, their use in science, industry and medicine is significantly restricted by their high cost and instability," comments Fairlie. "A holy grail in chemistry has been to find a way to reduce large proteins down to much smaller, simpler and cheaper molecules with the same activities…We have done exactly that, opening up exciting new avenues for chemists to downsize valuable human proteins and obtain affordable new diagnostics and drugs for the detection and treatment of human diseases."
The research was published in the journal, Nature Communications
Image: this graphic shows C3a as part of the complement system.
The complement system is made up of about 25 proteins that work together to “complement” the action of antibodies in destroying bacteria. Complement proteins circulate in the blood in an inactive form. When the first protein in the complement series is activated— typically by antibody that has locked onto an antigen—it sets in motion a domino effect. Each component takes its turn in a precise chain of steps known as the complement cascade. The end product is a cylinder inserted into—and puncturing a hole in—the cell’s wall. With fluids and molecules flowing in and out, the cell swells and bursts.