L50 Histo Lymphatic Flashcards
Compenents of lymphatic system (7)
Diffuse lymphatic tissue Lymphatic nodules Lymphatic nodes Lymphatic vessels Bone marrow Spleen Thymus
Lymphatic functions
drain excess interstitial fluid
Transport for hormones, nutrients, waste
Immune response
Diameter of lymphatic vessels
Larger to root of neck
Lymphatic duct sides
Right lymphatic duct: 1/4
Thoracic duct: 3/4
Endothelial cells in lymphatic tissue
Stain darker because of proteins in lymph
Lymphatic tissue histo
Thin walls
Large lumen
No RBC
B cells
Function
Type of immunity
Percent
Produce antibodies
Humoral immunity
20-30%
T cells
Function
Type of immunity
Percent
Attach and destroy cells
Cell mediated immunity
60-80%
Natural Killer cells
Function
Percent
Kill certain transformed cells
5-10%
Diffuse lymphatic tissue
What is it
Location
Capsule?
Accumulation of lymphocytes in lamina propria of alimentary canal, respiratory, urinary, reproductive tracts
No capsule
Lymphatic nodule
What is it
Location
Histo
Accumlation of lymphocytes in alimentary canal, respiratory, urinary, reproductive tracts
No capsule
Sharply defined
Secondary nodule contains
germinal center
mantle zone
Follicular dendritic cells
Aggregated lymphatic nodules found in (3)
Tonils
Ileum (peyer’s patches)
Appendix
MALT
GALT
BALT
Mucus associated lymphatic
- Gut: alimentary tract
- Bronchus: respiratory system
Lymph node: deep vs superficial cortex
Superficial: primary or secondary lymphatic nodules
Deep: no nodules, lets of T lymphocytes
Lymph node medulla
composed of
Medullary cords: groups of cells
Medullary sinuses: drainage of lymph
Cells of reticular meshwork
Reticular cells
Dendritic cells: APC
Macrophages: phago, APC
Follicular dendritic cells
Efferent vs afferent lymphatic vessel
Afferent comes in at any point along capsule
Efferent is at hilum
Lymph flow in node
Capsule Subcapsular sinus Trabecula Trabecular sinus Medullary sinus Efferent at hilum
Types of cells in
Nodular cortex
Deep cortex
Medulla
B cells
T cells
B cells
Most lymphocytes enter node thru
Thru high endothelial venules
Thymus
Cell maturation
Cortex has immature T cells
Medulla is where education takes place and holds mature T cells
Key sign of Thymus Histo
Hassall’s Corpuscle (small pink circle inside light medulla)
Hassall’s corpuscle is type __ epithelioreticular cell
Type 6
Red pulp
Composition
Blood filled venous sinueses surrounded by billroths cords
Billroth’s cords contain
red blood cells Macrophages lymphocytes plasma cells granulocytes
Billroths cord function
Bood filtration
White pulp
Composition
Lymphocytes agreggating around central arteries–>Periarterial lymphatic sheaths
White pulp
function
immune functions similar to lymph nodes
Red pulp vs white pulp staining
Red is lighter and white is darker
White pulp w/ germinal center has artery pushed to the side
