Chapter 21 - lymphatic

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IgG Neutralization (viruses, bacteria, toxins); agglutination; precipitation; complement activation; opsonization; natural killer cell activation (antibody-dependent cell-mediated cytotoxicity) IgM Neutralization, agglutination (great potential), complement binding (great potential) IgA Neutralization, agglutination (great potential) IgD BCR (B-cell receptor) IgE Produced during allergic reactions or as a result of a parasitic infection; activation of mast cells and basophils

Antibodies used to measure immunologic memory

IgM and IgG

How are t-lymphocytes arranged in the cortex?

Immature t-lymphocytes

Lymph

Interstitial fluid transported within lymph vessel

Primary Lymphatic tissue

Involved in formatioand mayuration of lymphocytrs Red Bone Marrow Thymus

2nd line of defense non specific mechanisms

(1) activities of various types of cells including neutrophils, macrophages, dendritic cells, basophils, mast cells, NK cells, and eosinophils; (2) chemicals such as interferon and complement; and (3) physiologic processes that include the inflammatory response and development of a fever. Each of these is discussed in detail in this section.

cytokine

*small, soluble proteins produced by cells of both the innate and adaptive immune system to regulate and facilitate immune system activity. *released from one cell and binds to a specific receptor of a target cell, where its action is similar to that of a hormone

Where are lymphatic capillaries found?

1. Intersped throughout aerolar connective tissue among blood capillary networks 2. Red bone marrow 3. Spleen 4. CNS

Lymphatic Movement into Capillary

1. Lymph originates as interstitial fluid in surrounding cells. 2. Moves passively into lymphatic capillaries due to HYDROSTATIC PRESSURE gradient

Lymph Contents

1. Water 2. Dissolved solutes (eg, ions) 3. 100 -200 grams of protein (leaked into interstitial space during capillary exchange) 4. Sometimes foreign material (cell debris pathogens, perhaps metastized cance)

Cells that serve as APC

1. Dendritic cells 2. macrophages 3.B-lymphocytes

5 cardinal signs of inflammation

1. Redness 2.Heat, 3. Swelling 4. Pain, 5.Loss of function

Hapten

1. cannot function as an antigen alone 2. attaches to carrier molecule & become antigenics and trigger an immune response

Name 2 branches of adaptive immunity Name the immune cell involved in each branch of adaptive immunity

1. cell mediated: t-lymphocytes 2. humoral: b-lymphocytes

Risks of a High Fever

1. changes in metabolic pathways and denaturation of body proteins 2.Seizures 3.irreversible brain damage at greater than 106°F 4. death (body temp)109°F.

Describe the specific locations of the tonsils.

1. pharyngeal tonsil is found in the posterior wall of the nasopharynx 2. palatine tonsils are located in the posterolateral region of the oral cavity 3. lingual tonsils are located along the posterior one third of the tongue.

Benefits of Fever

1. replication of bacteria and viruses 2. promotes interferon activity 3. increases activity of adaptive immunity 4. accelerates tissue repair. 5. increases CAMs on the endothelium of capillaries in the lymph nodes, resulting in additional immune cells migrating out of the blood and into the lymphatic tissue

List all the anatomic structures for the lymphatic system. including the lymph vessels, primary lymphatic structures, and secondary lymphatic structures.

1.lymphatic capillaries, 2.lymphatic trunks, and 3.lymphatic ducts. Primary: 1.Red bone marrow 2.thymus Secondary structures 1.tonsils 2.lymph nodes 3.spleen 4.lymphatic nodules 5.MALT.

name 2 processes following lymphocyte activation

1.lymphocyte proliferation 2. differentiation to form a clone of identical cells that includes memory cells.

in strep throat what structures swell up?

1.pharyngeal tonsil 2.cervical lymph node, 3.palatine tonsil.

Peyer's Patch

COMPOSITION collection of lymphatic nodules LOCATION mucosa and extending into the submucosa of the small intestine, especially the ileum. small patches throughout intestinal tract

Lacteals

Capillaries located within the GI tract. Allow for absorption of lipid soluble substances in GI tract

What body systems are supported by the lymphatic system?

Cardiovascular and immune.

Where is red bone marrow found

Fonzie valued ribs, steak, ox, and potatoes 1. Flat bones of the skull 2. Vertebrae 3. Ribs 4. Sternum 5. Osda coxae 6. Proximal epiphyses of each humerus and femur

Thymus

Function: T-lymphocyte maturation and differentiation characteristics: reaches a maximum weight of 30-50 grams at puberty most active in childhood until puberty then declines in size bi lobed Location: mediasteninum

What are the general functions and of the spleen? Indicate whether red pulp or white pulp is responsible for each function?

General Function: the spleen is responsible for the filtration of blood. reaches a maximum weight of 30-50 grams at puberty a) initiates an immune response when antigens are detected in the blood B) stores erythrocytes and platelets and hemolyzes old, defective ones C) phagocytizes bacteria and foreign debris from the blood WHITE PULP: white pulp of the spleen contains lymphocytes which monitor the blood for pathogens, and are capable of initiation an immune response. RED PULP the red pulp within the sinusoids of the spleen contains macrophages, which remove foreign substances, pathogens, and either old or defective erythrocytes and platelets.

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Helper T-lymphocytes are generals of the army; they recruit and regulate other immune cells. Cytotoxic T-lymphocytes are elite military forces; they engage in "cell-to-cell" combat against a specific foe. B-lymphocytes are the elite military forces that release "munitions" (antibodies) that are typically released from a distance

Secondary Lymphatic tissue

House lymphocytrs and other immune cells 1. Lymph nodes 2. Spleen 3. Tonsils 4. Lymphatic nodules 5. MALT

These antibodies are found in secretions of tears, sweat, and saliva ____ First antibodies secreted in response to a new antigen _____ Retained as monomers on the surface of B cells _____ Found in the mucosa of the gastrointestinal tract _____ Found in breast milk _____ Secreted as pentamers _____

IgA IgM IgM IgA IgA IgM

name the five types of lymphatic trunks and the regions of the body from which they drain lymph

Jugular trunks: drain lymph from both the head and neck Subclavian trunk: remove lymph from the upper limbs, breasts, and superficial thoracic wall Bronchomediastinal trunk: drain lymph from deep thoracic structures Intestinal trunks; drain lymph from most abdominal structures Lumbar trunks: remove lymph from the lower limbs, abdominopelvic wall, and pelvic organs

MALT

LOCATION: Large groups of lymphatic nodules in the mucosa of the gastrointestinal, respiratory, genital, and urinary tracts FUNCTION: The lymphatic cells in the MALT help defend against foreign substances that come in contact with mucosal membranes. Composition: small concentrations of lymphoid tissue

Thoracic Duct

Large LEFT lymph vessel in the chest that receives lymph from below the diaphragm and from the left side of the body above the diaphragm

Lymphatic Capillary Size

Larger in diameter than blood capillaries

Location of the spleen

Left upper quadrant of the abdomen Inferior to the diaphragm and adjacent to the ribs Lies lateral to the kidney and posterolateral to the stomach

Why is red bone marrow considered a primary lymphatic structure?

Red bone marrow is the site of production of all formed elements in the blood, including all lymphocytes; hence it is a primary lymphatic structure.

Lymphatic Capillaries

Smallest lymph vessel Microscopic, close-ended vessels that absorb interstitial fluid. Lack basement membrane Overlapping endothelial cells

Compare and contrast the red and white pulp of the spleen with respect to the anatomy and functions of each.

The white pulp of the spleen contains lymphocytes which monitor the blood for pathogens, and are capable of initiating an immune response. the red pulp within the sinusoids of the spleen contains macrophages, which remove foreign substances, pathogens, and either old or defective erythrocytes and platelets.

Where must t- lymphocytes travel to mature

Thymus

Define inflammation

an immediate, local, nonspecific event that occurs in vascularized tissue against a great variety of injury-causing stimuli. Inflammation occurs, for example, in response to a scratch of your skin, a bee sting, overuse of a body structure (e.g., pitching arm), or from proteolytic enzymes released by fungi.

What type of cell is required to activate both helper T-lymphocytes and naive cytotoxic T-lymphocytes?

antigen-presenting cell

APC (antigen presenting cell) role

any immune cell that functions specifically to communicate the presence of antigen to both helper T-lymphocytes and cytotoxic T-lymphocytes doorman announcing guest to Helper T and Cytotoxic T

complement system

It is composed of at least 30 plasma proteins that make up approximately 10% of the blood serum proteins. These proteins are collectively referred to as complement. The name is derived from how they complement, or work along with, antibodies (proteins produced by differentiated B-lymphocytes, which are described in section 22.8). Individual complement proteins are generally identified with the letter "C" followed by a number (e.g., C1, C2).

What substances typically are absorbed from the interstitial space into lymphatic capillaries?

lymphatic capillaries typically absorb water dissolved solutes, and small amounts of protein.

what type of lymph vessel consists solely of an endothelium and has one-way flaps that allow interstitial fluid to enter but not exist?

lymphatic capillary

what isn't an accurate description of lymphatic nodules?

lymphatic nodules are completely surrounded by a connective tissue capsule.

Describe the basic composition of a lymphatic nodule, and give examples in the body where lymphatic nodules may be found.

lymphatic nodules are small clusters of lymphatic cells with some extracellular matrix that are not completely surrounded by a connective tissue capsule. they are located within every organ of the body. they may also aggregate into larger structures such as MALT which is found in mucous membranes of the digestive and respiratory systems.

Describe the basic anatomy of a lymph node, how lymph enters and leaves the node, and the functions of each.

numerous lymphatic vessels will deliver lymphatic fluid to a lymph node. as the materials within the fluid percolate through the sinuses located in the medulla of the lymph node, they will be exposed to macrophages and lymphocytes. macrophages will remove foreign particles from the lymphatic fluid. lymphocytes will initiate an immune response upon exposure to the foreign particles.

Explain what distinguishes a primary lymphatic structrue from a secondary structure?

primary lymphatic structures, such as bone marrow and the thymus, are involved in the formation and maturation of lymphocytes. secondary structures' immune cells follow their formation and provide the site where an immune response is initiated. the major secondary structures include; tonsils, lymph nodes, spleen, lymphatic nodules, and MALT.

2nd line of defense skin SKIN

provide a physical barrier that very few microbes can penetrate, if the skin is intact. The cells of the skin also release a number of antimicrobial substances, including sebum, lysozyme, defensins, and dermicidin. Additionally, nonpathogenic microorganisms, termed the normal flora, reside on the skin and help prevent the growth of pathogenic microorganisms.

what is the fever inducing molecule?

pyrogens

Lymph is drained into the thoracic duct from which body region?

right lower limb

lymph is drained into the thoracic duct from which body region?

right lower limb

Right Lymphatic Duct

short vessel 1/2 in long that receives only the lymph that comes from the bodys superior right quadrant - the right side of the head, neck and thorax as well as the right upper extremity - it empties into the RIGHT SUBCLAVIAN VEIN near the heart - its opening is guarded by 2 pocket like semilunar valves to prevent blood from entering the duct.

Prion

small fragments of infectious proteins that cause disease in nervous tissue. Variant Creutzfeldt-Jakob disease (also known as bovine spongiform encephalopathy, or "mad cow disease") is an example.

Define Major Histocompatibility Complex (MHC)

specialized transmembrane protein an antigen must attach to. types: MHC I and MHC II

Aged erythrocytes are moved from circulation by the

spleen.

Compare Lymphatic Vessels and Small Veins

superficial lymphatic vessels adjacent to superficial veins Resemble small veins Both Contain: Intima, Media, and Externa Valve with in their lumen

How are the two types of T-lymphocytes arranged in the cortex and medulla?

the cortex of the thymus contains immature T-lymphocytes (pre-T-lymphocytes) and the medulla contains mature T-lymphocytes.

How does fluid enter and become "trapped" in the lymphatic capillaries?

the hydrostatic pressure of interstitial fluid separates the endothelial cells that form the lymphatic capillaries, allowing the interstitial fluid to enter the capillary. once inside, the fluid exerts pressure on the endothelial cells, closing the gaps, and trapping the fluid in the vessel.

What distinguishes a lymphatic trunk from a lymphatic duct?

the lymphatic trunks drain lymph from various regions of the body. the trunks merge into one of two distinct lymphatic ducts. each duct then returns the fluid back to the systemic circuit of the circulatory system.

Which major body regions drain lymph to the right lymphatic duct?

the right lymphatic duct receives lymph from (1) the right side of the head and neck (2) the right upper limb, and (3) the right side of the thorax.

Describe how the thymus's anatomy changes as we age.

the thymus continues to grow until puberty, when it reaches a maximum weight of 30 to 40 grams. cells within the thymus begin to regress after it reaches this size. Thereafter, much of the thymic tissue is replaced by adipose connective tissue.

Define Fever

defined as an abnormal elevation of body temperature (pyrexia) of at least 1°C (1.8°F) from the typically accepted core body temperature of 37°C (98.6°F)

Control center in brain that acts as thermostat?

hypothalamus

Describe what lymph is and draw a flow chart that illustrates what structures the lymph travels through to return to the blood.

interstitial fluid enters lymphatic capillaries and becomes lymph. interstitial fluid --> lymphatic capillaries--> Lymph Nodes--> Lymphatic trunks--> Lymphatic ducts--> Systemic veins

autoimmune disorders

involves the immune system reacting to self-antigens as if they were foreign Multiple sclerosis Diabetes Type 1

what is the function of the thymus?

it is the site of T-lymphocyte maturation.

what is not a function of the spleen?

it normally serves as a site for hemopoiesis during the adult life.

2nd line of defense Mucosal Membranes

line the openings of the body produce mucin that when hydrated forms mucus and also release lysozyme, defensins, and immunoglobulin A (IgA). In addition, harmless bacteria also live in the linings of the various tracts of the body and suppress the growth of other potentially more virulent types

What is accurate about lymph nodes?

lymph enters the lymph node thorough afferent lymphatic vessels.

Which lymphatic structures filter lymph? Which filter blood?

lymph nodes filter lymph, whereas spleen filters blood.

interstitial fluid that is absorbed into lymph vessels will be monitored by the ______ before the fluid is dumped into venous circulation

lymph nodes.

Which type of immunity would result in production of memory cells and lfifelong protection against an antigen

Active

MHC I cells presenting

All nucleated cells

Name granulocytes

Neutrophil Eosinophils Basophils

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Neutrophils are the "foot soldiers" that are the first to arrive at the site of infection. Macrophages are the "big eaters"—the cleanup crew that arrives at the injured or infected scene late and stays longer. Basophils/mast cells engage in chemical warfare that causes inflammation. NK cells serve as "security guards" that "search for and destroy" unwanted cells. Eosinophils are the "heavy artillery" to take on the "big guys" (parasites).

Lymph Origins & Production

Orignates as interstitial fluid surrounding tissue cells. During capillary exchange 3 liters of is not reabsorbed back into blood. This is absorbed by lymphatic capillaries thus becoming LYMPH.

Major Lymphocytes

T- Lymphocytes B-Lymphpcytes

lymphocytes formed in red bone marrow

T-lymphocytes (also called T-cells) and B-lymphocytes (also called B-cells).

Why is inflammation the most important benefit in the 1st line of defense?

movement of additional fluid from the blood through the infected or injured area and then into the lymph (washing the infected area)

Active Immunity

naturally: direct exposure artificially: vaccine

Passive

naturally: mother to child across placenta or breast milk artificially: transfer of serum containing antibody from a human or an animal

red bone marrow

primary a. Located within spongy bone of certain bones b. Formation of all formed elements; site of B-lymphocyte maturation

Name formed elements

Erythrocyte Platelets Granulocytes Agranulocytes

differential counts

An increase in neutrophils is associated with an acute bacterial infection. Monocytes may increase with chronic inflammatory disorders or tuberculosis. An increase in eosinophils occurs in response to a parasitic infection. An elevated number of lymphocytes generally is associated with viral infections or with chronic bacterial infections. In contrast, decreased lymphocyte counts can occur with HIV infection and sepsis (presence of a large number of pathogens in the blood).

Define lymph node

Description: Small, round, or oval encapsulated structures Varying size (1 - 25 millimeters) and number (500 - 700) throughout the body. Location: Along the pathways of lymph vessels where they serve as the main lymphatic organ Function: Filtering of lymph and removal of unwanted substances

Characterize lymph transport in terms of rate, volume, and ability to change.

Lymph transport is sporadic and much slower than that occurring in veins. About 3 liters of lymph enters the bloodstream in a 24-hour period. An increase in physical activity will cause lymph flow to increase, balancing the greater rate of fluid outflow from the vascular system

Describe the mechanisms by which lymphatic fluid is moved through the lymphatics.

Lymphatic fluid is moved through the lymphatics by the milking action of active skeletal muscles, pressure changes within the thorax during breathing, valves to prevent backflow, and pulsation of adjacent arteries.

Name 3 methods that move leukocytes from blood into the infected tissue

Margination is the process by which CAMs on leukocytes adhere to CAMs on the endothelial cells of capillaries within the injured tissue. The result is similar to "cellular Velcro." Neutrophils are generally the first to arrive and are short-lived, followed later by the longer-lived macrophages. Diapedesis (dī′ă-pĕ-dē-sis) is the process by which cells exit the blood by "squeezing out" between vessel wall cells, usually in the postcapillary venules, and then migrate to the site of infection (see section 18.3c). Chemotaxis is migration of cells along a chemical gradient (see section 18.3c). Chemicals released from damaged cells, dead cells, or invading pathogens diffuse outward and form a chemical gradient that attracts immune cells. Recruited cells also participate in the inflammatory response through the release of specific cytokines, such as granulocyte-macrophage colony-stimulating factor (GM-CSF), that stimulate leukopoiesis within red bone marrow (see section 18.3a). This helps account for the increase in leukocyte count that occurs during an active infection. Macrophages may also release pyrogens, such as interleukin 1 (IL-1), that induce a fever (see section 22.3e).

How are t-lymphocytes arranged in the medulla?

Mature t-lymphocytes

Agranulocytes

Monocytes Lymphocytes

How does lymph flow through a lymph node, and how is it monitored by macrophages and lymphocytes?

Numerous lymphatic vessels will deliver lymphatic fluid to a lymph node as the materials within the fluid percolate through the sinuses located in the medulla of the lymph node, they will be exposed to macrophages and lymphocytes. Macrophates will remove foreign particles form the lymphatic fluid. Lymphocytes will initiate an immune response upon exposure to the foreign particles.

How are primary lymphatic structures and secondary lymphatic structures differentiated? What are examples of each?

Primary lymphatic structures, such as bone marrow and thymus, are involved in the formation and maturation of lymphocytes. Secondary lymphatic structures' immune cells follow their formation an provide the site where an immune response is initiated. the major secondary lymphatic structures include the lymph nodes, spleen, tonsils, lymphatic nodules, and MALT.

MHC II cells presenting

Professional Antigen-Presenting Cells

What are the three main groups of tonsils and their function?

The three sets of tonsils are the pharyngenal, palatine, and lingual tonsils. Tonsils help protect against foreign substances that may be either inhaled or ingested.

What is the function of MALT in the mucosal linings of the gastrointestinal, respiratory, genital, and urinary tracts?

The lymphatic cells in the MALT help defend against foreign substances that come in contact with mucosal membranes.

Explain how the lymphatic system supports the functions of both the cardiovascular system and the immune system.

The lymphatic system provides for an alternative route for the return of fluid toward the heart in the systemic circuit. it also provides an opportunity for lymphocytes and macrophages to filter and process body fluids.

Which body regions have their lymph drained to the thoracic duct?

The thoracic duct drains lymph from everywhere except 1.right side of the head and neck 2.right arm 3.right side of the throacic cavity.

Describe the structural and functional relationship of the vessels of the blood vascular system and the lymphatic system

Vessels of the blood vascular system are relatively high-pressure conduits compared to vessels of the lymphatic system. The same mechanisms that promote venous return in blood vessels act within lymphatic vessels. Because lymphatics are usually packaged together in connective tissue sheaths with blood vessels, the pulsating expansions of the nearby arteries also promote lymph flow.

interferon

a category of cytokines that include (1) IFN-α and IFN-β produced by leukocytes and virus-infected cells and (2) IFN-γ produced by T-lymphocytes and NK cells.

Antigen

a substance that binds to a component of adaptive immunity protein or a large polysaccharide

cause of lymphedema

a. blockage of lymph vessels. There are several causes of obstructive lymphedema: b. Trauma or infection of the lymph vessels c.The spread of malignant tumors within the lymph nodes and lymph vessels d. Radiation therapy that results in scar formation in lymph vessels or nodes e. Any surgery that requires removal of a group of lymph nodes (e.g., breast cancer surgery when the axillary lymph nodes are removed)

Immunoglogic Memory

ability of the immune system to respond more rapidly and effectively to a pathogen that has been encountered previously.

Lymphedema

accumulation of interstitial fluid that occurs due to interference with lymph drainage in a part of the body. Interstitial fluid increases, and the affected area both swells and becomes painful. If lymphedema is left untreated, the protein-rich interstitial fluid may interfere with wound healing and can even contribute to an infection by acting as a growth medium for bacteria