Immunology-Lymphoid Structures Flashcards
Lmyph nodes- encapsulated, with trabeculae.
What does the follicle do?

Site of B cell localization and proliferation. In outer cortex. Primary follicles are dense and dormant and 2ndary follicles have pale central germinal centers and are active
What does the medulla in lymph nodes do?
Consists of medullary cords and medullary sinuses. edullary sinsuses communicate with efferent lymphatics and contain reticular cells and macropahges.
What does the paracortex in lymph nodes do?
Houses T cells. Region of cortex between follicles and the medulla. Contains high endothelial venules through which T and B cells enter from blood.
Not well developed in pts with DiGeorge
What is the lymph drainage of the head and neck?
cervical cluster
What is the lymph drainage of the lungs?
hilar nodes
What is the lymph drainage of the trachea and esophagus?
mediastinal
What is the lymph drainage of the upper limb, breast, and skin above umbilicus?
Axillary
What is the lymph drainage of the liver, stomach, spleen, pancreas, and upper duodenum?
Celiac nodes
What is the lymph drainage of the lower duodenu, jejunum, ieum, colon to splenic flexure?
Superior mesenteric
What is the lymph drainage of the colon from the splenic flexure to the upper rectum?
Inferior mesenteric
What is the lymph drainage of the lower retctum above the pectinate line, bladder, vagina (middle third), and prostate?
Internal iliac
What is the lymph drainage of the testes, ovaries, kidneys, and uterus?
Para-aortic nodes
What is the lymph drainage of the anal canal below the pectinate line, skin below the umbilicus (except popliteal territory) and scrotum?
Superfical inguinal
What is the lymph drainage of the dosrolateral foot and posterior calf?
Popliteal
Note that the right lymphatic duct drains the right side of body above the diaphragm and the thoracic duct drains everythign else into the junction of the left subclavian and internal jugular vein

pg 199 helps First AID
The marginal zone, in between the red pulp and white pulp, contains APCs and specialized B cells, and is where APCs capture blood-borne antigens for ecognition by lymphocytes

Sinusoids are long, vascular channels in the red pulp with fenestrated “barrel loop” basement membranes
T cells are found in the PALS within the white pulp of the spleen
B cells are found in the follicles within the white pulp

Lack of a spleen increases the risk of infection from what?
SHiNE SKiS
S. pneumo
H. influenza type B
N. meningitidis
E. coli
Salmonella spp.
Klebsiella pneumoniae
GBS
What are some clinical findings post-splenectomy?
- Howell-Jolly bodies (below)
- target cells
Thrombocytosis due to loss of sequestration and removal
Lymphocytosis

What is the role of the thymus?
This is the site of T-cell differentation and maturation. Encapsulated.
Derived from the 3rd pharyngeal pouch
Cotex is dense with immature T cells and the medulla is dense with mature T cells and Hassall corpuslces containing epithelial reticular cells
