Mouse NGF (2.5S) was isolated from mouse submaxillary glands by method of Mobley et al (1976) and is a form of beta-NGF that has identical biological properties. NGF is known to regulate the survival and development of certain sympathetic and sensory neurons. It is a dimer with 2 identical polypeptide chains and dimeric molecular weight of approximately 26,500 Da. Isolation and purification of NGF from mouse submaxillary glands yields preparations of NGF (2.5S) with identical biological activity but with cleavages at the amino terminus (with the loss of 8 amino acids) and/or at the carboxy-terminus (with the loss of arginine). These preparations are named 2.5 NGF (see reference below).