THYMUS
Primary lymphoid organ
Thymus – Structure
Capsule -> trabeculae (incomplete) -> dividing parenchyma into lobules
Cortex = peripheral zone
Medulla = central zone
Located in superior mediastinum
Thymus – Development
Thymus – General Overview
THymus = THird pharyngeal pouch
LYMPHOEPITHELIAL ORGAN
Endodermal cells -> Thymic epithelial cells / epitheliocytes
Bone marrow -> lymphoblasts -> to thymus -> reside in spaces between
“thymic epithelial cells” => LYMPHOEPITHELIAL ORGAN.
Thymus grows -> well developed in children -> regresses gradually in
adulthood -> involutes
Lymphatic tissue -> fibrous tissue
Primary lymphoid organ
Thymus – Structure
Capsule -> trabeculae (incomplete) -> dividing parenchyma into lobules
Cortex = peripheral zone
Medulla = central zone
Located in superior mediastinum
Thymus – Development
Thymus – General Overview
THymus = THird pharyngeal pouch
LYMPHOEPITHELIAL ORGAN
Endodermal cells -> Thymic epithelial cells / epitheliocytes
Bone marrow -> lymphoblasts -> to thymus -> reside in spaces between
“thymic epithelial cells” => LYMPHOEPITHELIAL ORGAN.
Thymus grows -> well developed in children -> regresses gradually in
adulthood -> involutes
Lymphatic tissue -> fibrous tissue
