Altered levels of nerve growth factor in the thymus of subjects with myasthenia gravis.

We have previously reported that nerve growth factor (NGF), a polypeptide known for its neurotrophic activities, is also involved in the differentiation and survival of immune cells, and that NGF and its high-affinity receptor are present in the thymus. We here demostrate that the thymus of humans affected by myasthenia gravis (MG) contains significant concentrations of NGF. These observations support our hypothesis of a role for NGF in the thymus and suggest that the changes observed in the thymus of subject with MG may have functional significance.