Graded distribution of the neural 2A10 antigen in the developing chicken retina.

During retinal histogenesis, post-mitotic cells become located in different tissue layers, where they differentiate into distinct cell types. In an attempt to elucidate mechanisms of cell differentiation, we have employed hybridoma technology in conjunction with various in vitro techniques. Here, we present monoclonal antibody 2A10, which binds specifically to the cell surface of neurons and outgrowing neurites. Within the retina 2A10 antigen expression is developmentally regulated being most pronounced during the period of tissue layer formation. Elevated antigen expression is limited to post-mitotic neurons as revealed by labeling with bromodeoxyuridine. Retinal ganglion cells, which are the first neurons to develop, appear not to influence the overall developmental regulation of the antigen in the retina, since elimination of these cells by virtue of optic nerve transection in ovo did not alter the antigen expression. The antigen is distributed in a graded fashion in the radial axis of the retina. Maximal immunoreactivity was found at the inner surface of the retina (optic fiber layer), whereas only minute reactivity was detected in the outermost layer. This graded distribution could possibly be involved in a topographic system providing positional information for differentiating neurons. Operationally, MAb 2A10 is a useful marker for retinal neurons, and provides a tool for establishing pure Müller glia cultures by complement-mediated cytolysis of retinal neurons.