A monoclonal antibody to beta-tubulin distinguishes a subset of neurons and axons in the chick ciliary ganglion.

A monoclonal antibody, called mabPS2, has been produced by injecting mice with purified postsynaptic densities from adult rat brain. The antibody reacts with an epitope of beta-tubulin which is not found on the alpha-tubulin subunit. In the chick ciliary ganglion mabPS2 reacts both with some large and some small neuron. mabPS2 also labels a subset of myelinated, as well as some unmyelinated axons. Higher magnification of longitudinal sections of axons shows that the reaction product is associated with microtubules. The nerve terminals on the ciliary neurons are also labelled and at higher magnification the label is seen to be distributed generally throughout the cytosol and especially concentrated on the membranes of synaptic vesicles. mabPS2 can therefore be used a a differentiation marker for neurons in chick ciliary ganglion.