How protofibrils form from Aβ-oligomers. (IMAGE) Forschungszentrum Juelich Caption Small Aβ oligomers (left: cryo-electron microscopy) are clumps consisting of just a few Aβ molecules. They cluster together to form short, worm-like structures known as protofibrils (right: atomic force microscopy). In an acidic environment, the Aβ oligomers form very quickly and cluster to form large particles from which protofibrils are separated following neutralization of the pH value (right, red arrows). Credit Forschungszentrum Jülich, HHU Düsseldorf / Wolfgang Hoyer Usage Restrictions Please give credit. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.