A neurofilament protein antibody selectively labels a large ganglion cell type in the human retina

An antibody (SMI-32) raised against the non-phosphorylated form of the neurofilament protein triplet (NFP) revealed immunoreactivity in the soma and dendritic arborization of a group of large ganglion cells in the human retina. In addition, a population of smaller somas was also faintly labeled with this antibody in the ganglion cell layer. The completely stained cells amounted to 44,000 and were non-uniformly distributed across the retina with a peak density of 100 cells/mm2 in the retinal periphery. The soma sizes increased about two-fold and dendritic field sizes about 3-fold with retinal eccentricity. The immunoreactive dendrites branched in the vitread sublamina of the inner plexiform layer. The dendritic branching pattern of these cells indicated that they correspond to the previously described shrub cells. Antibodies against NFP and neuropeptide Y showed colocalization of these markers in all of the completely stained cells.