multiple sclerosis

The MeDAS molecular probe works like a homing device. Injected into the body intravenously, it is programmed to seek out and bind only to myelin in the central nervous system, i.e., the brain, spinal cord and optic nerves. A positron-emitting radioisotope label on the molecule allows a PET scanner to detect the targets and quantify their intensity and location. The data can then be reconstructed into an image.

When the central nervous system is injured, oligodendrocyte precursor cells (OPC) migrate to the lesion and synthesize new myelin sheaths on demyelinated axons. Scientists at the Institute of Molecular Cell Biology at Johannes Gutenberg University Mainz (JGU) have now discovered that a distinct protein regulates the direction and movement of OPC toward the wound. The transmembrane protein NG2, which is expressed at the surface of OPCs and down-regulated as they mature to myelinating oligodendrocytes, plays an important role in the reaction of OPC to wounding.

This new study used cutting edge cell ablation technology to delete the nerve circuit that encodes heat and some forms of itch while preserving the circuitry that sense cold temperatures. This manipulation results in animals that were practically blind to heat, meaning they could no longer detect hot temperatures.

A study out today in the journal Cell Stem Cell shows that human brain cells created by reprogramming skin cells are highly effective in treating myelin disorders, a family of diseases that includes multiple sclerosis and rare childhood disorders called pediatric leukodystrophies.

Researchers have unlocked the complex cellular mechanics that instruct specific brain cells to continue to divide. This discovery overcomes a significant technical hurdle to potential human stem cell therapies; ensuring that an abundant supply of cells is available to study and ultimately treat people with diseases.

“We have developed a tremendous amount of information about these cells and how to produce them,” said Goldman. “We understand the different cell populations, their genetic profiles, and how they behave in culture and in a variety of animal models. We also have better understanding of the disease target environments than ever before, and have the radiographic technologies to follow how patients do after transplantation. Moving into clinical trials for myelin disorders is really just a question of resources at this point.”

This preliminary clinical trial shows small but significant benefits of minocycline in children with FXS. Other treatments for FXS are being investigated, including a new class of drugs called mGluR5 inhibitors. However, minocycline is the only targeted FXS treatment that is currently available by prescription. Because of its long history of use, the side effects and safety characteristics of minocycline are well known.