lymphatic system overview
DESCRIPTION
Immune Response Spring 2007. Lymphatic System Overview. Functions. Draining interstitial fluids Return lymph fluid to veins Transporting dietary lipids Protecting against invasion. Lymphatic Vessels. Lymphatic capillaries Slightly larger than blood capillaries - PowerPoint PPT PresentationTRANSCRIPT
Lymphatic System Overview
Immune ResponseSpring 2007
Functions
Draining interstitial fluids Return lymph fluid to veins
Transporting dietary lipids Protecting against invasion
Lymphatic Vessels Lymphatic capillaries
Slightly larger than blood capillaries Allow interstitial fluid to flow in but not out
Lymphatic Vessels Cap. unite to form lymphatic vessels
Resemble veins Thinner walls and more valves Lymph nodes-masses of B cells & T cells
Thoracic Duct Drains most of the body
Right Lymphatic Duct Drains upper right side of body
Organs
2 groups based on function Primary lymphatic organs
Sites where stem cells mature into B cells & T cells
Red bone marrow & thymus Secondary lymphatic organs &
tissues Lymph nodes, spleen, lymphatic nodules
Thymus Consists of T cells,
macrophages, and epithelial cells
Produce thymic hormones Promote the
proliferation & maturation of T cells
Lymph Nodes 600 bean shaped organs Usually occur in groups Contain B cells that develop into
plasma cells Secrete antibodies, T cells, &
macrophages Filter lymphatic fluid Method of metastasis of cancer
Lymph Node
Spleen Largest mass of lymphatic tissue in
body 2 tissue types
White pulp▪ Lymphatic tissue▪ Consists of lymphocytes and macrophages
Red pulp▪ Blood filled sinuses▪ Splenic tissues- RBC’s, macrophages,
lymphocytes, plasma cells, and granular leukocytes
Spleen
Enlarged Spleen
Lymphatic Nodules
Not enclosed with a capsule Includes tonsils
Nonspecific Resistance to Disease 1st line of defense-Skin and mucous
membranes Epidermis Mucous membranes▪ Hairs▪ Cilia
Lacrimal apparatus Saliva Sweat
Nonspecific Resistance to Disease 2nd line of defense-internal defenses
Antimicrobial proteins Phagocytes Natural killer cells Fever Inflammation
Antimicrobial Proteins
Found in blood & interstitial fluid Interferons
Interfere with viral replication Complement
Cytolysis, chemotaxis, oponization Transferrins
Bind iron = inhibit growth of some bacteria
Natural Killer & Phagocytosis Natural killer (NK)
Cytolysis Phagocytes
Phagocytosis-ingestion of microbes or other particles
During infection monocytes enlarge into macrophages
Phagocytosis
Inflammation
Can be caused by pathogens, abrasions, chemical irritations, distortion or disturbances of cells, extreme temps
4 symptons Redness Pain Heat swelling
Inflammation (con’t) 3 stages
1. Vasodilation and increased permeability of blood vessels▪ Increased blood flow to area
2. Phagocyte emigration▪ Neutrophils, then monocytes, then
wandering macrophages3. Repair▪ Pus-WBC’s & dead tissue debris
Inflamatory Response