Template talk:Spleen Timeline Table
From Embryology
Embryonic
Feature | ||
---|---|---|
Carnegie stage 14 to 17
appears as a bulge in the dorsal mesogastrium. Mesothelium pseudostratified. | ||
Mesothelium (pseudostratified} replaced with high columnar cells and then low columnar cells. | ||
Basement membrane present after this stage. | ||
Hematopoietic cells detected. | ||
Spleen is now apparent. Mesenchymal cells differentiated from cells in dorsal mesogastrium. Sinus and hilus formation after this stage. | ||
Arteries and veins parallel entries at this stage. | ||
Human data.[1] Links: spleen | Kyoto Collection | Timeline human development |
Fetal
Fetal data from study from week 15 (GA 17) to week 38 (GA 40).[2]
- week 15 (17 GA) - alpha-smooth muscle actin (alpha-SMA)-positive reticulum cells scattered around the arterioles.
- week 18 to 21 (20 - 23 GA) - alpha-SMA-positive reticulum cells increase in number and began to form a reticular framework. An accumulation of T and B lymphocytes occurred within the framework, and a primitive white pulp was observed around the arterioles.
- week 22 (24 GA) - antigenic diversity of the reticular framework was observed, and T and B lymphocytes were segregated in the framework. T lymphocytes were sorted into the alpha-SMA-positive reticular framework, and the periarteriolar lymphoid sheath (PALS) was formed around the arteriole. B lymphocytes aggregated in eccentric portions to the PALS and formed the lymph follicle (LF). The reticular framework of the LF was alpha-SMA-negative.
- week 24 (26 GA) - marginal zone appeared in the alpha-SMA-positive reticular framework around the white pulp.
Combined
Feature | ||
---|---|---|
Carnegie stage 14 to 17
appears as a bulge in the dorsal mesogastrium. Mesothelium pseudostratified. | ||
Mesothelium (pseudostratified} replaced with high columnar cells and then low columnar cells. | ||
Basement membrane present after this stage. | ||
Hematopoietic cells detected. | ||
Spleen is now apparent. Mesenchymal cells differentiated from cells in dorsal mesogastrium. Sinus and hilus formation after this stage. | ||
Arteries and veins parallel entries at this stage. | ||
Feature | ||
reticulum cells (alpha-smooth muscle actin-positive) scattered around the arterioles | ||
reticulum cells increase in number and began to form a reticular framework. Accumulation of T and B lymphocytes within this framework, and a primitive white pulp was observed around the arterioles. | ||
reticular framework antigenic diversity, and T and B lymphocytes were segregated in the framework. T lymphocytes were sorted into the alpha-SMA-positive reticular framework, and the periarteriolar lymphoid sheath (PALS) was formed around the arteriole. B lymphocytes aggregated in eccentric portions to the PALS and formed the lymph follicle (LF, reticular framework alpha-SMA-negative). | ||
marginal zone appears in reticular framework around the white pulp. | ||
Human embryonic data[1] and fetal data [2] Links: spleen | Kyoto Collection | Timeline human development |
- ↑ 1.0 1.1 Endo A, Ueno S, Yamada S, Uwabe C & Takakuwa T. (2015). Morphogenesis of the spleen during the human embryonic period. Anat Rec (Hoboken) , 298, 820-6. PMID: 25403423 DOI.
- ↑ 2.0 2.1 Satoh T, Sakurai E, Tada H & Masuda T. (2009). Ontogeny of reticular framework of white pulp and marginal zone in human spleen: immunohistochemical studies of fetal spleens from the 17th to 40th week of gestation. Cell Tissue Res. , 336, 287-97. PMID: 19255788 DOI.