Ana

How can lymph nodes be used to determine if any or how much cancer has spread in the body?

If the cancer cells are not destroyed in the node, they can seed the growth of a metastatic tumor. The degree of metastasis can be determined by finding the lymph nodes most distant from the original site of the cancer that are "normal." This is also the reason the lymph nodes draining the site of a malignant tumor are removed and examined for the presence of abnormal cells at the same time the tumor itself is excised.

Why is systemic lupus erythematosus (SLE) considered one of the most serious autoimmune diseases?

In SLE, autoantibodies are produced against a wide variety of substances, including blood cells (erythrocytes, platelets, and lymphocytes), clotting proteins, phospholipids, and especially nuclear contents such as the nucleic acids and histones. Thus, virtually every cell of the body is subject to attack. Tissue damage most often occurs when antibody antigen complexes are deposited in body tissues. The most common site of deposition is the basement membrane of the glomerulus in the kidney, leading to renal complications.

-released by cells infected by VIRUS -interrupt virus sex -attack NK cells to the invasion -reduces inflammation -aids in fighting some cancers

Interferons

-released by lymphocytes & macrophages -cause T-cells to be more sensitive to germs -stimulate B-cell activity to make antibodies -stimulates inflammation response-stimulates fever

Interleukins

wage chemical warfare on virally infected cells by firing lethal proteins at them

Killer T cells

fluid contents of lymphatic vessels, similar in composition to interstitial fluid

Lymph

lymphoid organs that monitor the composition of lymph

Lymph nodes

What is lymphadenitis and what may it indicate?

Lymphadenitis can be triggered by a wide variety of pathogens, including bacteria, viruses, fungi, and protozoans. Streptococcal infections, tuberculosis, cat-scratch disease, primary syphilis, and genital herpes.

List the components of the lymphatic system.

Lymphatic vessels, lymph, Lymphocytes, Lymphoid tissues and lymphoid organs

extensive collection of lymphoid tissues linked with the epithelial of the digestive, respiratory, urinary, and reproductive tracts

MALT

Selena has been diagnosed with renal failure and is admitted to the hospital for a kidney transplant. What is major histocompatibility (MHC) and why is it important to find a donor that has the same MHC?

MHC molecules are important components of the immune system because they allow T lymphocytes to detect cells, such as macrophages, that have ingested infectious microorganisms. In uninfected healthy cells, the MHC molecule presents peptides from its own cell (self peptides), to which T cells do not normally react. When the transplant recipient's immune system detects the nonself antigens on the transplanted tissue, immune responses are triggered. These rejection responses are characterized as hyperacute, acute, or chronic, depending on the time course.

quickly recognize the viruses as a foreign threat. They begin destroying viruses by engulfing them

Macrophages

The specificity of an antibody is determined by the

variable segments of light and heavy chains.

Anatomically, lymph vessels resemble

veins.

stimulated by the release of interleukins from macrophages, helper T cells, and interferons. There cells join the attack on virally infected cells. They also fight cancer cells

Natural Killer cells

Identify the two forms of active immunity and the two forms of passive immunity.

Naturally acquired active immunity and Artificially induced active immunity. Naturally acquired passive immunity and Artificially induced passive immunity.

-released by pathogen infected cells -attract macrophages & microphages -prevents pre-mature departure

Phagocyte-activating chemicals

List the body's innate (nonspecific) defenses.

Physical barriers, phagocytes, immune surveillance, interferons, complement, inflammation, fever

A sample of lymph contains an elevated number of plasma cells. Would you expect the number of antibodies in the blood to be increasing or decreasing? Why?

Plasma cells produce and secrete antibodies, so observing an elevated number of plasma cells would lead us to expect increasing levels of antibodies in the blood.

List the four general properties of adaptive immunity.

Specificity: Specific defense is activated by specific antigen Versatility: Millions of different lymphocyte populations produced Memory: First exposure triggers development of memory cells, second exposure to an antigen triggers faster, stronger, longer-lasting immune response Tolerance: Exists when immune system does not respond to normal antigens

lymphoid organ important for the phagocytosis of RBC's, lymphocyte production

Spleen

How would blockage of the thoracic duct affect the flow of lymph?

would impair the drainage of lymph from inferior to the diaphragm and from the left side of the head and thorax, retarding the return of lymph to the venous blood and promoting the accumulation of fluid in the limbs.

help the immune system gear down as the body begins to conquer viruses

Suppressor T cells

The three classes of lymphocytes found in blood are

T cells, B cells, and NK cells.

A defense against abnormal cells and pathogens inside living cells is provided by

T cells.

A lymphoid organ; the site of T-cell formation & maturation

Thymus

A lymphoid nodule in the wall of the pharynx; 3 pairs

Tonsils

-released by macrophages & cytotoxic T-cells -kills some tumor cells -slows growth of other types of tumor cells -stimulates leukocyte production -causes fever

Tumor necrosis factors (TNF'S)

try to replicate before the immune system can gear up

Viruses

A decrease in the number of cytotoxic T cells would affect which type of immunity?

Would affect cell-mediated immunity, reducing the effectiveness of T cells in killing foreign cells and virus-infected cells.

An active antibody is shaped like a

Y.

When an antigen appears, the immune response begins with the

activation of specific T cells and B cells.

The most important antibody action in the body is

activation of the complement systems.

Immunity resulting from natural exposure to an antigen in the environment is called

active immunity.

Inappropriate or excessive immune responses to antigens are

allergies.

A specific defense mechanism is always activated by

an antigen.

When an immune response mistakenly targets normal body cells and tissues, the result is

an autoimmune disorder.

Why are antibiotics prescribed for bacterial tonsillitis but not for viral tonsillitis?

antibiotics don't fight viruses, Antibiotics only help in people who have a bacterial infection

Antibody secretion by memory B cells is the secondary response to

antigen exposure.

The reason the primary response takes time to develop is that

antigen-activated B cells must differentiate into plasma cells.

Misguided antibodies that function against normal body cells and tissues are called

autoantibodies.

In order for an antigenic molecule to be a complete antigen, it must

be immunogenic and reactive.

Normal lymphocyte populations are maintained through lymphopoiesis in the

bone marrow and thymus.

Cytotoxic T cells are the primary providers of

cell-mediated immunity.

T-cell activation leads to the formation of cytotoxic T cells and memory T cells that provide

cell-mediated immunity.

T cells are involved with _______ and ________ attack pathogens.

cell-mediated responses; directly

Destruction of target cells by the local release of cytokines, lymphotoxins, or perforin involves

cytotoxic T cells.

Identify the four types of T cells.

cytotoxic, helper, memory, and suppressor T cells. Cytotoxic T cells destroy bacteria, fungi, transplanted tissue. Helper T cells activated by exposure to antigens bound to Class II MHC proteins. Memory T Cells remain "in reserve". and Suppressor T Cells Activated slowly by exposure to antigens bound to Class I MHC proteins,

Suppressor T cells act to

depress the responses of other T cells and B cells.

The two major ways the body "carries out" the immune response are

direct attack by T cells and circulating antibodies.

Define pathogen.

disease-causing organisms

When T cells become less responsive to antigens,

fewer cytotoxic T cells respond to an infection.

Lymphocytes that assist in the regulation and coordination of the immune response are

helper T and suppressor T cells.

With age, B cells become less active due to a reduced number of

helper T cells.

The lymphatic system

helps maintain normal blood volume, fights infection, and eliminates variations in the composition of interstitial fluid.

B cells are involved with _______ and create a chemical attack on _______.

humoral responses; antigens

The body's ability to resist infection and disease through the action of specific defenses is called

immunity.

When the immune system fails to develop normally or the immune response is blocked in some way, the condition is called an

immunodeficiency disease.

The ability to demonstrate an immune response upon exposure to an antigen is called

immunological competence.

Because tumor cells are not eliminated as effectively in the elderly, the incidence of cancer reflects the fact that

immunological surveillance declines.

NK cells sensitive to the presence of abnormal cell membranes are primarily involved in

immunological surveillance.

With advancing age the immune system becomes

increasingly susceptible to viral and bacterial infection and less effective at combating disease.

The basic principle behind vaccination to prevent disease involves

induced active immunity.

The antibodies produced by active plasma cells bind to the target antigen to

inhibit its activity, destroy it, and remove it from solution.

A rise in the level of interferon in the body indicates what kind of infection?

interferon are chemical messengers interfering with virus replication inside cells, a rise in the level means indicates that interfering with virus replication and preventing virus synthesis is taking place at this time.

The protein that interferes with the replication of viruses are

interferon.

The hormones released by synthesizing cells that make neighboring cells resistant to viral infection, thereby slowing the spread of the virus, are called

interferons.

If the thymus gland failed to produce thymic hormones, which population of lymphocytes would be affected?

lack of thymic hormones would drastically reduce the population of T lymphocytes by preventing their differentiation from lymphoid stem cells.

The major components of the lymphatic system include

lymphatic vessels, lymph, lymphoid organs, and lymphocytes.

The structures in the lymphatic system that act as a "way station" for cancer cells are the

lymphnodes.

When the immune "recognition" system malfunctions, activated B cells begin to

manufacture antibodies against other cells and tissues.

The binding of an antigen to an antibody can result in

neutralization of the antigen, agglutination or precipitation, and complement activation.

Explain the difference between nonspecific defense and specific defense.

nonspecific immunity are things that protect the body from various bacterias, viruses, and pathogens. Specific immunity are things that protect the body from specific pathogens.

Immunity that results from the transfer of antibodies to an individual from some other source is called

passive immunity.

The first line of cellular defense against pathogens is

phagocytes.

The body's nonspecific defenses that are present at birth include

physical barriers and phagocytic cells, immunological surveillance and fever, interferons, complement, and inflammation.

The cells responsible for the production of circulating antibodies are

plasma cells.

Circulating proteins that reset the thermostat in the hypothalamus, causing a rise in body temperature, are called

pyrogens.

What postsurgical treatment should be initiated to prevent Selena's rejection of the organ?

Acute rejection occurs about 2 weeks after the transplant as the recipient develops antibodies against the donor's HLA antigens. Chronic rejection occurs after months to years of normal transplant function as a result of a weak immune response against minor HLA antigens in the transplant. Immunosuppressive drugs allow for transplants between less compatible donors and recipients,

How can the presence of an abnormal peptide within the cytoplasm of a cell start an immune response?

An abnormal peptide in the cytoplasm of a cell would cause an immune response by being presented on the plasma membrane of the cell by a MHC protein.

Y-shaped proteins designed specifically to recognize a particular viral or bacterial invader. They bind to the virus and neutralize it

Antibodies

The four general properties of specific defenses include

specificity, versatility, memory, and tolerance.

Define sensitization.

Antigens enter B cell, then are displayed on surface-bound to Class II MHC proteins, process called sensitization.

The antigenic determinant site is that portion of the antigen's exposed surface where

the antibody attacks.

tube connected to the junction of the large and small intestines ; long thought to have no purpose

Appendix

What are autoimmune diseases?

Autoimmune diseases are disorders in which the immune system mistakenly recognizes normal tissues as foreign and initiates immune-mediated destruction of the tissue cells.

(produced in bones) mature into plasma cells, which in turn produce antibodies

B cells

Hemocytoblasts in the bone marrow produce lymphoid stem cells that generate

B cells, NK cells, and T cells.

The type of lymphocytes that produce antibodies are

B cells.

Would the primary response or the secondary response be more affected by a lack of memory B cells for a particular antigen? Explain.

Because production of a secondary response defends on the presence of memory B cells and memory T cells formed during a primary response, the secondary response would be more affected by a lack of memory B cells for a particular antigen.

The nonspecific defense that breaks down cell walls, attracts phagocytes, and stimulates inflammation is

the complement system.

Explain the difference between cell-mediated (cellular) immunity and antibody-mediated (humoral) immunity.

Cellular immunity results of T cell defense specifically against pathogens inside living cells. And humoralimmunity result of B cell defense specifically against pathogens in body fluids.

Where are Class I MHC proteins and Class II MHC proteins found?

Class I MHC protein in the plasma membrane of all nucleated cells, Class II MHC Proteins found in membranes of lymphocytes and antigen-presenting cells

Lymphatic organs found in the lymphatic system include

the spleen, the thymus, and lymph nodes.

Most of the lymph returns to the venous circulation by the way of the

thoracic duct.

What signs, symptoms, and test results lead Zach's physician to suspect a lymphoma?

He is losing weight, his lymph nodes are swollen, and he has been experiencing night sweats. He also seems to be scratching more often than normal. Lymphocyte levels high = 30%

the battle managers of the immune system, emit signals to B cells and killer T cells to help join the attack

Helper T cells

What treatment will likely be prescribed for Zach? What is his prognosis?

Hodgkin disease is treated with radiation and chemotherapy, with a survival rate of 70% to 80%. He also need a lymph node biopsy used to diagnose it.

Distinguish between the 3 different types of malignant lymphomas.

Hodgkin disease, non Hodgkin lymphoma, and Burkitt lymphoma. Non-Hodgkin lymphoma is more common than Hodgkin lymphoma, and Non-Hodgkin lymphoma may arise in lymph nodes anywhere in the body, whereas Hodgkin lymphoma typically begins in the upper body, such as the neck, chest or armpits. Burkitt lymphoma affects predominantly children and young adults in central Africa, where it is thought to involve an insect-borne virus.