TheThe LymphaticLymphatic SystemSystem
LymphaticLymphatic VesselsVessels andand OrgansOrgans IncludingIncluding thethe GlymphaticsGlymphatics The Lymphatic System
Taken from: Basmajian,J.V., Grant’s Method of Anatomy, Baltimore MD, Williams & Wilkins Co. 1975 Functions of the Lymphatic System • 1) Fluid balance • Tissue fluid homeostasis & pressure • 2) Nutritional • Lipid and protein absorption • 3) Host defense • Immune surveillance • Transport of cytokines & chemokines Lymphoid Organs Lymphoid Organs
• Primary lymphoid organs • Thymus and bone marrow • Secondary lymphoid organs • Lymph nodes, spleen, aggregate nodules • Tertiary lymphoid organs • Chronic inflammatory ectopic lymphoid tissue Lymphoid Organs
Primary Secondary Lymphoid Lymphoid Organs Organs
Oppenhein JJ, Shevach EM. Immunophysiology. New York: Oxford University Press, 1990. ? Tertiary Lymphoid Organs
• “Portable” lymph nodes • Associated with sites of chronic inflammation • Similar in construction to SLOs • Lack a capsule • May develop at sites of insufficient drainage TLO Structure
Ruddle, N. H. (2014). "Lymphatic vessels and tertiary lymphoid organs." J Clin.Invest 124(3): 953-959. Lymphatic Vessels
• Terminal vessels • Afferent and efferent (based on the node) • Chemical signature: • LYVE-1 and PROX-1 expressing • VEGF-2 and VEGF-3 receptors • Neuropilin-2, angiopoeitin-1 and CCL21 Outline
• Afferent lymph vessels • Lymph nodes • Efferent lymphatic vessels • Thoracic duct • Specific organ drainage patterns • Diaphragm Tissue Fluids Formation of Interstitial Fluids
Mortimer, P.S. & Rockson, S.G., New developments in clinical aspects of lymphatic disease, Journal of Clinical Investigation 124(3)915-921 (2014) Formation of Interstitial Fluids
Mortimer, P.S. & Rockson, S.G., New developments in clinical aspects of lymphatic disease, Journal of Clinical Investigation 124(3)915-921 (2014) Development of Lymphatic Vessels
Pattern, B. M. (1946). Human Embryology. Philadelphia, The Blakiston Company. PROX-1
Transcription factor that controls a hierarchy of events
Homolog of Prospero, a homeobox transcription factor in Drosophila Master regulator for the development of lymphatic vessels
Prospero in Shakespeare’s Tempest Lymphangiogenesis in Development
Cueni, L. N. and M. Detmar (2008). "The lymphatic system in health and disease." Lymphat.Res.Biol. 6(3-4): 109-122. Development of Lymphatic Vessels
Lymphangiogenesis from veins
Lymphangiogenesis from lymphangioblasts
Yang,Y, and Oliver, G., Development of the mammalian lymphatic vasculature , Journal of Clinical Investigation 124(3)888-897 (2014)
27870 Lymphangiogenesis in Adults • Only seems to occur in certain situations: • Tissue repair • Inflammation • Tumorigenesis • Mechanisms: • Sprouting from pre-existing vessels • De novo formation from circulating endothelial progenitor cells Lymphatic Terminals
•Blind endings •Lacking a basement membrane •“Oak-leaf” shaped cells •Interdigitating cells borders that form one-way valves Lymphatic Endothelial Cells & Terminals
Lack of a continuous basement membrane
Breslin, J. W. (2014). "Mechanical forces and lymphatic transport." Microvasc.Res. 96: 46-54. The Lymphatic Capillary Primary Valves
Bazigou,E., Wilson, J.T. & Moore, J.E., Primary and secondary lymphatic valve development: Molecular, functional, and mechanical insights, Microvascular Research: in print (2014)
27874 The Lymphatic Capillary Lymphatic Smooth Muscle Cells
Secondary Valves
Primary Valves The Lymphatic Valve Afferent lymphatic vessel
Lymph Node Capsule Contractile Nature of the Lymphangion
Breslin, J. W. (2014). "Mechanical forces and lymphatic transport." Microvasc.Res. 96: 46-54. Lymphangion
• Endothelial cell lining
• Thin wall with smooth muscle rings
• Ends with valve flaps Contractile Nature of the Lymphangion
Zawieja DC. Contractile physiology of lymphatics. LymphatResBiol 2009;7:87-96. Lymph Movement: Intrinsic Mechanism • Lymphangion • Filling phase of 5-8 seconds • Contraction phase of 1 second • Constrict at regular intervals • Refractory period of up to 4 seconds • Co-ordination between up and downstream lymphangions Lymphatic System drainage through a Lymph Node
Taken from: Agur, A.M. and Dalley, A.F., Grant’s Atlas of Anatomy, Lippincott, Williams & Wilkins Co., Philadelphia, PA 2009 Lymphatic System drainage through a Lymph Node
Breslin, J. W. (2014). "Mechanical forces and lymphatic transport." Microvasc.Res. 96: 46-54. The Lymphatic Afferent Vessel Axillary Nodes
Inguinal Nodes
Cervical Nodes (cancerous) Lymph Node SuperficialSuperficial CortexCortex
DeepDeep CortexCortex
MedullaMedulla Lymph Nodes
Bellanti JA. Immunology III. Philadelphia: W.B. Saunders Company, 1985. Cellular Components
•Stromal cells: fibroblast reticular cells •T-cell and B-cell compartmentalization •APCs such as DCs and FDCs •HEVs •Macrophages High-Endothelial Venules
Oppenhein JJ, Shevach EM. Immunophysiology. New York: Oxford University Press, 1990. High Endothelial Venules High Endothelial Venules in Lymph Nodes
Medulla
Subcapsular sinus Efferent LEC vessel
Afferent vessel FRC
High Endothelial Venule
Bellanti, J. A. (1985). Immunology III. Philadelphia, W.B. Saunders Company. High Endothelial Venules
Ager A. High Endothelial Venules and Other Blood Vessels: Critical Regulators of Lymphoid Organ Development and Function. Front Immunol 2017;8:45. High-Endothelial Venules
• Communication route between blood and lymph node • Adressins - Lymphocytes entering • Aquaporin-1 - water exiting Ager, A. (2017). "High Endothelial Venules and Other Blood Vessels: Critical Regulators of Lymphoid Organ Development and Function." Front Immunol 8: 45. Development of ectopic HEV secondary to Ager, A. (2017). "High Endothelial Venules and Other Blood Vessels: Critical Regulators of Lymphoid Organ tissue inflammation Development and Function." Front Immunol 8: 45. Lymphatic System Pathology
• Inflammation • Cancer • Infection Pathological Alterations in the Lymphatic System
Liao,S., and Padera, T.P., Lymphatic function and immune regulation in health and disease, Lymphatic Research and Biology, 11:(3)136-143 (2013)
27866 Inflammation-induced Lymphangiogenesis
•Macrophages as a driving force •VEGF-A and VEGF-D producing cells: •Neutrophils •Epithelial cells and keratinocytes •Fibroblastic reticular cells Inflammation-induced Lymphangiogenesis
Tan, K. W., et al. (2014). "Inflammatory lymphangiogenesis: cellular mediators and functional implications." Angiogenesis 17(2): 373-381 Tumor-induced Lymphangiogenesis
Zheng, W., et al. (2014). "Lymphangiogenic factors, mechanisms, and applications." J Clin.Invest 124(3): 878-887. Tumor-induced Lymphangiogenesis
Zheng, W., et al. (2014). "Lymphangiogenic factors, mechanisms, and applications." J Clin.Invest 124(3): 878-887. Metastatic Spread
Cueni, L. N. and M. Detmar (2008). "The lymphatic system in health and disease." Lymphat.Res.Biol. 6(3-4): 109-122. 0009C-1026 Distal to the Node
• Efferent lymphatic vessels • Cisterna chyli • Thoracic duct / Right lymphatic duct • Venous circulation The Lymphatic Efferent Vessel Collecting Vessel TD
Aorta Thoracic Thoracic Duct Duct Thoracic Duct Cisterna Chyli Cisterna Chyli & Thoracic Duct Thoracic Duct Thoracic Duct Thoracic Duct Thoracic Duct Lymph Movement: Regulation • Endothelial cells produce nitric oxide
• Smooth muscle cells • Transmitter receptors • Gap junctions
• Smooth muscle continuity between lymphangions Lymph Movement: Autonomic Nervous System
• Lymph vessels are richly innervated
• Lymph flow responds to sympathetic stimulation
• An α-adrenergic and purinergic (ATP) excitatory mechanism exist
• A β-adrenergic inhibitory mechanism exists Lymph Movement: Characteristics
• Autoregulation – pacemaker cells • Stroke frequency and volume are related
• Load associated changes in pump activity
• Pump failure at high loads Lymph Movement: Extrinsic Mechanisms
• Intermittent compression over drainage territory can increase lymphatic flow fourfold
• Systolic event of 1 second
• Dyastolic event of 5-8 seconds
• Mean time between contractions: 7.6 s (+/- 6.7s) Lymph Movement: Extrinsic Factors
• Skeletal muscle and limb movement • Heart and vascular pulsations • Respiratory motions • Intestinal peristalsis • Surface massage Inflammation and The Lymphatic System
• Inflammatory cytokines stimulate the lymphatic pump system (stroke volume) • Benoit and Zawieja, 1992
• Lymphatics carry cytokines away from the site of inflammation Lymphatic Drainage of the Head & Neck Drainage Routes 1. Arachnoid gr from the Cranium to the Cervical Lymphatics 2. Olfactory
3. Glymphatics
4. Meningeal
Laman JD, Weller RO. Drainage of cells and soluble antigen from the CNS to regional lymph nodes. JNeuroimmunePharmacol 2013;8:840-856. Arachnoid Granulations Olfactory Tract Olfactory Tract Olfactory Tract Cribriform Plate of the Ethmoid Bone Glymphatic System
Jessen NA, Munk AS, Lundgaard I, Nedergaard M. The Glymphatic System: A Beginner's Guide. NeurochemRes 2015;40:2583-2599. Dural Lymphatic Channels Superficial Cervical Lymphatic Drainage
Schaeffer JP. Morris' Human Anatomy, A complete Systemic Treatise. New York: The Blakiston Division, McGraw-Hill Book Company, Inc., 1953. Deep Cervical Lymphatic
Drainage 40 pt 40 pt
Schaeffer JP. Morris' Human Anatomy, A complete Systemic Treatise. New York: The Blakiston Division, McGraw-Hill Book Company, Inc., 1953. Lymphatic Drainage of the Extremities Lymphatics of the Upper Extremity Lymphatics of the Upper Extremity Lymphatics of the Upper Extremity Lymphatics of the Lower Extremity
Lymphatic Drainage of the Thorax
Lymphatics of the Thorax Lymphatics of the Thorax Lymphatics of the Thorax Bronchial-AssociatedBronchial-Associated LymphaticLymphatic TissueTissue BALTBALT Intraparenchymal Bronchus Innervation of the Airway
Bronchospasm Lymphatic Drainage of the Gastrointestinal System Lymphatics of the Liver Lymphatics of the Celiac Region Lymphatics of the Celiac Region Lymphatics of the Superior Mesenteric Region Lymphatics of the Superior Mesenteric Region Intestinal Villi Intestinal Lacteal Lymphatics of the Ileocecal Junction
Anterior view Posterior view Lymphatics of the Inferior Mesenteric Region Lymphatics of the Posterior Body Wall The Celiac Territory: The Foregut
• Distal esophagus, stomach and proximal duodenum • Pancreas, liver and gall bladder • Spleen The Superior Mesenteric Territory:
• Small intestine • Distal duodenum • Jejunum • Ileum • Proximal large intestine • Cecum • Ascending colon • Transverse colon The Inferior Mesenteric Territory: The Hindgut
• The distal large intestine • Descending colon • Sigmoid colon • Rectum Three Divisions of The GI System
Para- Blood Sympathetic Lymphatic Origin sympathetic Supply Innervation Drainage Innervation Celiac Celiac Celiac Vagus Foregut Ganglia Lymph Artery Nerve T5-T9 Nodes
Superior Superior Superior Mesenteric Vagus Mesenteric Midgut Mesenteric Ganglia Nerve Lymph Artery T9-T12 Nodes
Inferior Pelvic Inferior Inferior Mesenteric Splanchnic Mesenteric Hindgut Mesenteric Ganglia Nerves Lymph Artery L1-L2 S2-S4 nodes The Gut-Associated Immune System Mucosal Associated Immune Systems • Gut associated lymphatic tissue • GALT • Bronchial associated lymphatic tissue • BALT • Mucosal associated lymphatic tissue • MALT • Skin associated lymphatic tissue • SALT The GI Mucosal Immune System
• Gut-Associated Lymphatic Tissue • T-cells • B-cells • Macrophages and dendritic cells • Neutrophils • Eosinophils • Mast cells GALT Functions
• Tolerant of overlying microbiota to prevent excessive local or systemic inflammatory response. • Control gut microbiota to prevent overgrowth and systemic translocation
Cell Types in the Gut Lining • Stem cells • Enterocytes • Paneth cells • Goblet cells • M-cells • IEL cells GALT
• Controlled/ Physiologic Inflammation • Oral Tolerance Distribution of GALT
• Diffuse lymphatic tissue • Efferent limb of the immune response
• Aggregate (nodular) lymphatic tissue • Afferent limb of the immune response Peyer’s Patches in the Ileum
Peyer’s Patches Nodular Lymphatic Tissue
• M-cells (Microfold cells) • Antigen-presenting cells • Cortex of nodule: T-Cells and B-cells • Core of nodule: B-cells Gut-Associated Lymphatic Tissue
Oppenhein JJ, Shevach EM. Immunophysiology. New York: Oxford University Press, 1990. The GALT Afferent System
A B C TLR Sensory System Activation of the GALT
• Antigen is endocytosed by the M-cells • Presented to dendritic cell • Activation of CD+4 T-cells and B-cells • B-cells differentiate for IgA-production • T-cells then mature into memory cells IgA Transport
Binds to lumenal antigens
Promotes agglutination
Removal thru mucus layer Activated IgA B-Cell Trafficking
• Leaves the organized MALT and enters lymphatic channels • Mesenteric nodes to Aortic nodes • Thoracic duct to systemic circulation MALT Circulation Cellular Trafficking in the Immune System
Sell S. Immunology, Immunopathology and Immunity. New York: Elsevier, 1987. Dermal Lymphatics
Mortimer, P.S. & Rockson, S.G., New developments in clinical aspects of lymphatic disease, Journal of Clinical Investigation 124(3)915-921 (2014) Stage 1
Stage 2
Role of the GALT in Oncogenesis Microbiota Associated with Oncogenesis in
• Citrobacter rodentatum • Helicobacter hepaticas • Bacteroides fragilis - endotoxin-induced Brain-Gut-Immune Axis & the Gut Microbiota Enteric Nervous System Interaction
• Altered activity of the interstitial cells of Cajal – the pacemakers
• Alternating periods of quiescence and enhanced peristalsis Irritable Bowel Syndrome
J. D. Wood. Pathophysiology underlying irritable bowel syndrome. In: Physiology of the gastrointestinal tract, edited by L. R. Johnson, Amsterdam:Academic Press Elsevier, 2006, p. 1009-1031 Lymphatic Drainage of the Pelvis
Lymphatic Drainage of the Thoraco-abdominal Diaphragm Fluid Systems Related to the Diaphragm:
The Cisterna Chyli Diaphragmatic Absorption Rate:
• Rhythmic movement of the diaphragm • Changing intraperitoneal pressures • Body posture
• Uptake of lymph on exhalation M. F. Abu-Hijleh, O. A. Habbal, and S. T. Moqattash. The role of the diaphragm in lymphatic absorption from the peritoneal cavity. J.Anat. 186:453-467, 1995. M. F. Abu-Hijleh, O. A. Habbal, and S. T. Moqattash. The role of the diaphragm in lymphatic absorption from the peritoneal cavity. J.Anat. 186:453-467, 1995. M. F. Abu-Hijleh, O. A. Habbal, and S. T. Moqattash. The role of the diaphragm in lymphatic absorption from the peritoneal cavity. J.Anat. 186:453-467, 1995. M. F. Abu-Hijleh, O. A. Habbal, and S. T. Moqattash. The role of the diaphragm in lymphatic absorption from the peritoneal cavity. J.Anat. 186:453-467, 1995. M. F. Abu-Hijleh, O. A. Habbal, and S. T. Moqattash. The role of the diaphragm in lymphatic absorption from the peritoneal cavity. J.Anat. 186:453-467, 1995. D. Negrini, S. Mukenge, M. Del Fabbro, C. Gonano, and G. Miserocchi. Distribution of diaphragmatic lymphatic stomata. J Appl.Physiol 70 (4):1544-1549, 1991 M. F. Abu-Hijleh, O. A. Habbal, and S. T. Moqattash. The role of the diaphragm in lymphatic absorption from the peritoneal cavity. J.Anat. 186:453-467, 1995.
Diaphragm Movements
• Relaxation - loads the diaphragm with peritoneal fluids • Contraction - expels fluid from the diaphragmatic lymphatics • Paralysis of the diaphragm slows movement of lymph in the thoracic duct Whats the most important “take-home” message? Movement