spleen white pulp morphology trait spleen marginal zone morphology trait Any measurable or observable characteristic related to the shape, structure, color, or pattern of the zone between the red and white pulp of the spleen containing numerous macrophages and lymphocytes, and a rich plexus of sinusoids supplied by white pulp arterioles carrying blood-borne antigens. Note that there is no consensus in the literature about which compartments constitute the white pulp or the ramifications of the microvasculature. In addition, notable differences exist between humans and rodents. In this ontology, the marginal zone has been included as part of the white pulp. Trait.ontology VT:0002362 splenic marginal zone morphology trait