Is the spleen a preferential site of blood cell production in the human fetus?
Information about the status of the spleen as a preferential site of blood cell production in the human fetus is relevant to generalizations about the ontogeny of haematopoietic microenvironments and to speculations about the pathogenesis of myeloid metaplasia. Such information has been accumulated in a comparison of populations of blood cell precursors derived from the blood, the spleens and the livers of human fetuses during the fourth, fifth, sixth and seventh months of gestation. During this period, the spleen does not contain populations of erythroblasts or granulocyte precursors that could not have been derived from the blood. It is inferred that in the human fetus the spleen is not a preferential site of blood cell production between the fourth and seventh months of gestation. Like any other site, the spleen may however accommodate intravascular blood cell precursors, which may proliferate and differentiate in human fetal blood.
Thomas
D B
DB
School of Biology and Medical Sciences, University of St. Andrews, Scotland, UK.
D001773:Blood Cells / Q000166:cytology* / Q000378:metabolism; D005333:Fetus / Q000166:cytology* / Q000196:embryology* / Q000378:metabolism; D006411:Hematopoiesis, Extramedullary / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D013154:Spleen / Q000166:cytology* / Q000196:embryology* / Q000378:metabolism