Abstract
The monoclonal human granulocyte antibody B4, 3 shows reactivity with structures in the external granular layer of the developing rabbit cerebellum. This reactivity is first observed at post-conceptional day 19–20 and disappears at postnatal day 5–6. The reactivity in the immature rabbit cerebellum is distributed in a longitudinal pattern of bands positive and negative for this monoclonal antibody.