Lymphatic system

Edited by: Dr. Talebi

Dendritic cells

• Interdigitating Dendritic Cells

• Follicular Dendritic Cells

• Germinal Center Dendritic Cell

• Langerhans’cell

•Located in peripheral tissues or

lymphoid tissues

•They can be activated in •They can be activated in

inflammatory conditions

•Have the ability to uptake, process

and present antigens to T cells. They

are “professional” APC

Lymphatic gland

cortex

capsule

medula

trabecula

AFEF

Lymph node

Cortex and medulla

Cortical zone

Medulary cords & siuses(silver)

Spleen

White & red pulps of spleen

Red pulp

Splenic blood circulation

Siusoidal circulation

Thymic lobule

cortical thymocytes cortical thymocytes

subcapsular

region

outer cortical

cortical thymocytes

apoptotic thymocytes

deep cortical

cortico-medular

junction

medular region

macrophages

septum

reticuloepithelial cells

dendritic interdigitated

cells

Hassall corpuscules

medular epithelilal

cells

Infant thymus

The relationship between epithelial reticular cells and thymus

lymphocytes. Note the desmosomes and the long processes of epithelial

reticular cells extending among the lymphocytes.

Thymic (hassels corpuscle)

Adult thymus(senile changes)

F

Adult thymus(senile changes)

Lymphatic follicle in chorion of stomach

Diffused lymphatic tissue

Lymphatic tissue of intestinal wall

mucosa immunity in the intestine