abnormal spleen morphology abnormal spleen perifollicular zone morphology 2010-07-29T01:22:05Z MP:0010245 MPheno.ontology Note that there is no consensus in the literature about whether the perifollicular zone (which does not exist in rodents) is part of the splenic red or white pulp. Notable differences in the structure of the spleen exist between humans and rodents. In this ontology, the marginal sinus (which doen not exist in human) has been included as part of the white pulp and may be the rodent functional equivalent of the human perifollicular zone. any structural anomaly of the compartment located between the marginal zone and the red pulp harboring scattered B and T lymphocytes csmith