[MT] Immune System pt.4 - Thymus Region Cortex and Medulla

Which region of the thymus is densely populated by darkly staining T lymphoblasts or thymocytes?

Cortex

What provides mechanical support for developing T lymphoblasts in the thymic cortex?

Cortical epithelial cells

Where does T cell differentiation and selection occur in the thymus?

Thymus

What structure in the thymic cortex prevents unregulated exposure of developing T lymphoblasts to blood antigens?

Blood-thymus barrier

Thymus Cortex Promotes T cell ---- and ---- within the thymus

differentiation
proliferation

Consists of epithelial reticular cells surrounded by a basal lamina, and the endothelial cells joined by tight junctions that surround capillaries within the cortex

Blood-thymus barrier

Blood-thymus barrier is formed when the epithelium forms --- around the blood vessels

sheath

what region of thymus is lightly staining with T lymphocytes?

Medulla

What region of thymus has fewer T lymphocytes which is the reason it stains lighter?

Medulla

Most characteristic feature of the medulla and a histologic characteristic

Hassall corpuscles or thymic corpuscles

Hassall corpuscles or thymic corpuscles is large concentric aggregates of --------- that is variable in size

Thymic Epithelial Cells

Hassall corpuscles or thymic corpuscles secretes --- htat regulate dendritic cell activity in the thymus

cytokines

Hassall corpuscles or thymic corpuscles promote the development of ---------- for peripheral tolerance

regulatory T cells

Densely packed with immature thymocytes, site of differentiation & selection.

Cortex

Contains fewer lymphocytes and Hassall's corpuscles.

Medulla