Localization of a neurectoderm-associated cell surface antigen in the developing and adult rat

The distribution of a neurectoderm-associated carbohydrate antigen (termed D1.1) in tissues of the developing and adult rat was determined using indirect immunofluorescent techniques. The antigen was detected as early as embryonic days 8 and 9 when it was localized to cells within the developing neural plate and neural tube. As the central nervous system (CNS) developed, the anti-D1.1 antibody labeled neuroepithelial cells but not terminally differentiated neurons or glial cells. In addition, the notochord and somatic mesoderm were labeled transiently with the antibody. Outside of the CNS, the antibody labeled dorsal root ganglia neurons, adrenal chromaffin cells and cells of the kidney glomerulus. These tissues were labeled at embryonic day 14 and the labeling persisted in the adult. We used a sensitive immunoautoradiography assay to identify antigenic gangliosides present in extracts of these tissues. The anti-D1.1 antibody recognized a ganglioside of kidney and adrenal glands that has a chromatographic mobility identical to that of the D1.1 antigen previously identified from cell lines and developing cerebellum. However, the antibody bound to a separate and distinct set of gangliosides present in extracts of adult dorsal root ganglia. Thus, the carbohydrate sequence recognized by the antibody can be associated with more than one molecular species of ganglioside. These results demonstrate that within the context of the developing CNS, the D1.1 antigen is a stage-specific embryonic antigen, but, as is the case with other cell surface carbohydrate antigens, is also found on a limited but developmentally unrelated set of tissues in the adult.