Chapter 21: The Immune System: Innate and Adaptive Body Defenses
What is the antigen challenge, and where does it usually take place?
What is the antigen challenge, and where does it usually take place? -the antigen challenge is the first encounter between an immunocompetent lymphocyte and an invading antigen -it usually takes place in the spleen or a lymph node, but may happen in any lymphoid tissue
Immunocompetence:-occurs in one specific organ of the adaptive immune system -is the ability of individual cells to recognize a specific antigen by binding to it -prevents intercellular communication so that only specific cell types respond to the invader -requires exposure to an antigen
is the ability of individual cells to recognize a specific antigen by binding to it
Natural killer (NK) cells:-are also called cytotoxic T cells -are a type of phagocyte -are cells of the adaptive immune system -can kill cancer cells before the immune system is activated
can kill cancer cells before the immune system is activated
The process whereby neutrophils and other white blood cells are attracted to an inflammatory site is called:-diapedesis -chemotaxis -margination -phagocytosis
chemotaxis
Select the correct definition about tissue grafts: -isografts are between identical twins -allografts are between different species -xenografts are between individuals of the same species -autografts are between two genetically identical individuals
isografts are between identical twins
Which of the following is not characteristic of the adaptive immune system? -it is antigen-specific -it is systemic -it has memory -it is specific for a given organ
it is specific for a given organ
Monoclonal antibodies are used for the diagnosis of all of the following except:-juvenile diabetes -hepatitis -rabies -pregnancy
juvenile diabetes
____ predominate at the sites of chronic infections:-basophils -eosinophils -macrophages -B cells
macrophages
Phagocyte mobilization involves:-diapedesis, during which cells line up against the capillary wall -margination, which is the process of white cell movement through the walls of capillaries into injured tissues -mainly neutrophil and macrophage migration into inflamed areas -monocytes as the most active phagocyte
mainly neutrophil and macrophage migration into inflamed areas
Which of the following is the correct sequence of events in phagocytosis? -adherence, digestion, killing, ingestion, chemotaxis -chemotaxis, ingestion, digestion, adherence, killing -chemotaxis, adherence, ingestion, digestion, killing -ingestion, adherence, chemotaxis, digestion, killing
chemotaxis, adherence, ingestion, digestion, killing
Which of the following statements is incorrect or false? -haptens lack immunogenicity unless attached to protein carriers -class 1 MHC molecules are built into the plasma membranes of all body cells -class II MHC molecules appear only on the surface of antigen-presenting cells, thymic cells, and T cells that have been activated by exposure to antigens -MHC proteins are the cell's identity markers
class II MHC molecules appear only on the surface of antigen-presenting cells, thymic cells, and T cells that have been activated by exposure to antigens
Major innate mechanism that mediates destruction of foreign substances in the body:-interferon -regulatory T cells -complement -helper T cells -APCs
complement
Select the correct statement about the function of antibodies: -antibodies may directly destroy "invaders" -neutralization is the process by which antibodies cause invading cells to clump together -complement fixation is the main mechanism by which antibodies provide protection -the most potent agglutinating agent is IgG
complement fixation is the main mechanism by which antibodies provide protection
Which of the following is characteristic of antibodies? -carbohydrate structure -composed of heavy and light polypeptide chains -three binding sites per antibody monomer -incapable of being transferred from one person to another
composed of heavy and light polypeptide chains
Antibody functions include all of the following except: -binding and inactivating chemical toxins released by bacteria or other microorganisms -cross-linking cell-bound antigens on red blood cells when blood types are properly matched -linking soluble antigens together so that they fall out of solution -targeting foreign cells so that complement proteins can cause cellular lysis
cross-linking cell-bound antigens on red blood cells when blood types are properly matched
Toll-like receptors (TLRs) trigger the release of ____ to attract white blood cells to the scene: -cytokines -histamine -prostaglandins -complement
cytokines
____ are released by activated T cells and macrophages to mobilize immune cells and attract other leukocytes into the area:-cytokines -perforins -interleukin 1 proteins -interleukin 2 proteins
cytokines
The only T cells that can directly attack and kill other cells are the:-regulatory cells -helper cells -cytotoxic cells -plasma cells
cytotoxic cells
The antibody molecule is held together by ____ bonds: -disulfide -hydrogen -amino acid -sodium
disulfide
Helper T cells:-bind tightly to target cells and release a lymphotoxin called perforin -often function to decrease the immune response -release B7 proteins -function in the adaptive immune system activation
function in the adaptive immune system activation
Small molecules that bind with self-proteins to produce antigenic substances are called:-haptens -antibodies -ions -reagins
haptens
The primary immune response: -occurs more rapidly and is stronger than the secondary response -occurs when memory cells are stimulated -is another name for immunological memory -has a lag period while B cells proliferate and differentiate into plasma cells
has a lag period while B cells proliferate and differentiate into plasma cells
A 36 year old man enters the hospital in an extremely debilitated condition. He has purple-brown skin lesions (symptom of Kaposi's sarcoma) and a persistent cough. A physical examination reveals swollen lymph nodes, and lab tests find a very low lymphocyte count. Information taken during the personal history reveals that he has multiple sex partners with whom he frequently engages in unprotected sex. What is likely to be the man's problem and what is his outlook?
he is probably suffering from AIDS -his outlook is poor once the disease has progressed to this advanced stage -there is no cure and drug therapy has had limited short-term success
Which of the following cells is the most critical cell in immunity? -B cell -helper T cell -cytotoxic T cell -APC
helper T cell
Stimulate the proliferation of other lymphocytes:-interferon -regulatory T cells -complement -helper T cells -APCs
helper T cells
A ____ is a cell hybrid formed from the fusion of tumor cells and B lymphocytes.
hybridoma
Adaptive defense system: -inflammatory response and skin and mucous membranes -immune response -inflammatory response -intact skin and mucous membranes
immune response
Third line of defense: -inflammatory response and skin and mucous membranes -immune response -inflammatory response -intact skin and mucous membranes
immune response
Delayed hypersensitivities: -are mediated by B cells -include allergic contact dermatitis -include anaphylactic shock, a systemic vasodilation that results in inadequate blood delivery to all tissues -do not involve T cells
include allergic contact dermatitis
Second line of defense: -inflammatory response and skin and mucous membranes -immune response -inflammatory response -intact skin and mucous membranes
inflammatory response
Innate defense system: -inflammatory response and skin and mucous membranes -immune response -inflammatory response -intact skin and mucous membranes
inflammatory response and skin and mucous membranes
First line of defense: -inflammatory response and skin and mucous membranes -immune response -inflammatory response -intact skin and mucous membranes
intact skin and mucous membranes
Interferons: -are virus-specific, so that an interferon produced against one virus could not protect cells against another virus -act by increasing the rate of cell division -interfere with viral replication within cells -are routinely used in nasal sprays for the common cold
interfere with viral replication within cells
Small proteins secreted by virus-containing cells: -interferon -regulatory T cells -complement -helper T cells -APCs
interferon
Regulatory T cells:-release cytokines that increase the activity of cytotoxic T cells and activated B cells -decrease their activity as antigenic stimulus decreases -may function in preventing autoimmune reactions -are the most thoroughly understood T cells
may function in preventing autoimmune reactions
Pure antibody preparations specific for a single antigenic determinant are called ____ antibodies
monoclonal
Cancer cells and virus-infected body cells can be killed before activation of adaptive immunity by:-natural killer cells -T lymphocytes -B lymphocytes -pinocytosis
natural killer cells
What is the role of interferon in defense against disease? -protects cells that have not yet been infected by viruses -protects cells that have not yet been infected by bacteria -activates the complement mechanism -activates the inflammatory process
protects cells that have not yet been infected by viruses
Which of the following is characteristic of complete antigens? -small molecules -reactivity with an antibody -contain many repeating chemical units -inhibit production of antibodies
reactivity with an antibody
Dampen the activity of both T cells and B cells: -interferon -regulatory T cells -complement -helper T cells -APCs
regulatory T cells
Which of the following is not a function of the inflammatory response? -prevents the spread of the injurious agent to nearby tissue -replaces injured tissues with connective tissue -disposes of cellular debris and pathogens -sets the stage for repair processes
replaces injured tissues with connective tissue
Clonal selection of B cells:-occurs during fetal development -results in the formation of plasma cells -cannot occur in the presence of antigens -only occurs in the secondary immune response
results in the formation of plasma cells
Elderly people tend to develop cancer more frequently than younger people. Give an explanation for this observation that relates to immune function.
-as one ages, the efficiency of the immune system begins to decline -this may allow cancer to become established more easily
A young girl requires a liver transplant due to failure of her liver to function. What is required for her to have a good prognosis and why?
-the ABO and other blood group antigens of the donor and recipient must be determined -next, donor and recipient tissues are matched as closely as possible -following surgery she must receive immunosuppressive therapy to keep her body from rejecting the new liver as foreign tissue
What are some of the drawbacks of passive humoral immunity?
-the effects are short lived -it does not trigger memory cell production -your body degrades the antibodies
What are monoclonal antibodies? How are they produced, and what are some of their clinical uses?
=monoclonal antibodies are pure antibody preparations that exhibit specificity for a single antigenic determinant -they are produced from the progeny of a single B cell hybridoma "clone", prepared by injecting a specific antigen into a lab animal and then harvesting sensitized B cells from its spleen -the cells are mixed with myeloma cells and incubated, and the resulting hybridoma cells produce the monoclonal antibody -they are used for the diagnosis of pregnancy, certain sexually transmitted diseases, hepatitis, rabies, and for other purposes
____ refers to a group of at least 20 plasma proteins that normally circulate in an inactive state and are a major mechanism for destroying foreign substances in the body
Complement
____ cells are the only T lymphocytes that can directly attack and kill other cells.
Cytotoxic T
____ is an autoimmune disease that severely impairs renal function.
Glomerulonephritis
Protects mucosal barriers:-IgG -IgD -IgE -IgA -IgM
IgA
Along with IgM, this is a B cell receptor: -IgG -IgD -IgE -IgA -IgM
IgD
Involved in allergies:-IgG -IgD -IgE -IgA -IgM
IgE
The antibody that becomes bound to mast cells and basophils and causes the cells to release histamine and other chemicals is ____.
IgE
Main antibody of both primary and secondary immune response:-IgG -IgD -IgE -IgA -IgM
IgG
Activates complement: -IgG -IgD -IgE -IgA -IgM
IgM
____ is a dangerous condition where the cytokines are released unchecked, making the capillaries very leaky, and thus depleting blood fluids.
Septic shock or Sepsis
Select the correct statement about immunodeficiency: -severe combined immunodeficiency (SCID) disease is an acquired condition -the causative agent in acquired immune deficiency syndrome (AIDS) is a virus that recognizes CD4 proteins -Hodgkin's disease is a hereditary immunodeficiency found in children -the most common form of immunodeficiency is graft-versus-host (GVH) disease
the causative agent in acquired immune deficiency syndrome (AIDS) is a virus that recognizes CD4 proteins
A woman comes into the hospital emergency room complaining that she is having problems swallowing and her neck is swelling. She was involved in an automobile accident a couple days ago but only bruised her neck. What could be the problem?
the woman is suffering from Hashimoto's thyroiditis -the automobile accident injured the thyroid gland and released thyroidglobulin into the bloodstream -the immune system has mounted an attack on the thyroid gland
Which statement is true about T cells? -they usually directly recognize antigens, which then activates a subpopulation of killer cells -their proliferation is enhanced by interleukins 1 and 2 -once activated, they cannot secrete cytokines -they will develop into cytotoxic T cells if antigen is complexed with class II MHC proteins
their proliferation is enhanced by interleukins 1 and 2
After receiving penicillin intravenously, a 32 year old male patient has an anaphylactic reaction. The nurse understands that therapeutic management includes what critical items?
therapeutic management includes speed in recognition of signs and symptoms of an anaphylactic reaction because death can occur within minutes -maintaining an open airway is critical, because the bronchioles constrict, making it difficult to breathe
Why are regulatory T cells important to the immune process?
they are vital in the final stopping of an immune response after the antigen is inactivated -they may also help prevent autoimmune reactions
Which of the following is true of immediate hypersensitivities? -they are also called type IV hypersensitivities -they are adaptive immune responses to disease organisms -they include allergic contact dermatitis -they involved IgE antibodies and the release of histamine from mast cells and basophils
they involved IgE antibodies and the release of histamine from mast cells and basophils
Select the correct statement about the prevention of immune attack on "self": -the development of tolerance is specific to B cells only -neutrophils capable of binding to self-antigens are chemically inactivated -tolerance to self is due to the action of foreign antigens that inactivate the immune response to one's own tissues -tolerance is developed during fetal life
tolerance is developed during fetal life
Which of the following is not an autoimmune disease? -multiple sclerosis -type II diabetes -systemic lupus erythematosus -glomerulonephritis
type II diabetes
Graft rejection may be caused by:-using a xenograft -use of immunosuppressive drugs -treatment with antilymphocyte serum -total body irradiation
using a xenograft
The redness and heat of an inflamed area are due to a local hyperemia caused by: -vasodilation -vasoconstriction -phagocyte mobilization -production of complement and interferon
vasodilation
____ are grafts taken from another animal species
xenografts
Max is bitten by a rattlesnake while on a camping trip. His friends immediately apply ice packs to the bitten area to slow the spread of the protein-based toxin. They then rush his to an emergency facility. What treatment would be given and why?
-Max could be given an immune serum to the rattlesnake venom, thereby conferring passive immunity -the reason for passive immunization is that the venom could kill the person before active immunity could be established -the passive immunity would last until the "borrowed" antibodies naturally degraded in the body -no immunological memory would be established because B cells are not activated
Children born without a thymus must be kept in a germ-free environment if they are to survive. Explain why this is necessary.
-if the thymus fails to develop, the T cells will not mature and become immunocompetent -if T cell function is disrupted, there is no resistance to disease
List briefly and discuss innate body defenses to disease.
-innate body defenses to disease include surface membrane barriers, such as the skin and mucous membranes, as the first line of defense -not only do the skin and mucous membranes act as a physical barrier to microorganisms, but they also secrete chemicals such as saliva, sebum, mucus, and HCl that kill microorganisms -innate cellular defenses include the use of phagocytes and natural killer cells -inflammation response includes vasodilation, increased vascular permeability, ad phagocyte mobilization -antimicrobial substances such as interferon and complement are also produced as innate defenses by the body
Name four autoimmune diseases.
-multiple sclerosis -myasthenia gravis -Graves disease -juvenile (type I) diabetes -systemic lupus erythematosus -glomerulonephritis -rheumatoid arthritis
What the the signs of inflammation, and how does inflammation serve as a protective function?
-the four signs of inflammation are swelling, redness, heat and pain -the signs are caused by local vasodilation and increased capillary permeability -this is of benefit because the process helps to dilute harmful substances that may be present; brings in large quantities of oxygen, nutrients, and cells necessary for the repair process; and allows the entry of clotting proteins -pain helps immobilize the injury
What is the most likely type of hypersensitivity associated with an agonizingly itchy case of poison ivy, appearance of hives after eating shellfish, or a positive TB test?
-the hypersensitivity associated with poison ivy is delayed hypersensitivity allergic contract dermatitis -hypersensitivity associated with hives is a local anaphylactic reactions -hypersensitivity associated with a positive TB test is delayed hypersensitivity
Why do schools require inoculations for childhood diseases such as mumps, measles, and whooping cough? Why are the inoculations of value?
-the inoculations are required to try to prevent epidemics of these microbiological infections -the inoculations are of great benefit in preventing the diseases because the vaccines cause immunity to the pathogens by stimulating both the formation of protective antibodies and the establishment of immunological memory against future infection
Nursing care of a patient with acquired immune deficiency syndrome (AIDS) includes monitoring of T lymphocyte counts. Explain why.
-the primary defect in patients with AIDS is depletion of helper T cells and therefore the cell-mediated response -this immunodeficiency makes the patient more susceptible to infection and unusual cancers
Tom gets a cut on his hand. After several days he notes swelling, pain, heat and redness. Upon opening the wound to relieve the pressure, the presence of pus is noted. What has happened to the wound?
-the wound has become infected probably with bacteria -the initial symptoms indicate acute inflammation -pus indicates the presence of dead or dying neutrophils, broken-down tissue cells, and living and dead pathogens
What are two general mechanisms by which autoimmune diseases could arise?
1) appearance of new self-proteins in the circulation that have not previously been exposed to the immune system 2) an immune response to foreign antigens resembling self-antigens
Present the double activation signal to T cell:-interferon -regulatory T cells -complement -helper T cells -APCs
APCs
____ is the most common type of immediate hypersensitivity.
Allergy
Select the correct statement about complement:-an adaptive immune mechanism is often involved in directing complement to its target -complement can be activated through three pathways: classical, secondary, and alternate -the membrane attack complex consists of complement proteins C3s through C5 -complement proteins C1 through C9 act exclusively in the classical pathway an adaptive immune mechanism is often involved in directing complement to its target Which of the following is true about the number of binding sites per functional antibody unit? -IgD contains 4 binding sites -IgA contains 6 binding sites -IgG contains 6 binding sites -IgM contains 10 binding sites
IgM contains 10 binding sites
Which of the following statements regarding NK cells is a false or incorrect statement? -NK cells are a type of neutrophil -NK cells are present in the blood, spleen, lymph nodes, and red bone marrow -NK cells attack cells that display abnormal MHC antigens -NK cells attack cancer cells and virus-infected body cells
NK cells are a type of neutrophil
____ cells can lyse and kill cancer cells and virus-infected body cells before the immune system is activated.
Natural killer
A physician orders Tylenol for a temperature greater than 101 degrees F. The patient's temperature is 100.4*F. Explain the rationale for not medicating a fever of 100.4*F.
a mild or moderate fever is an adaptive response that seems to benefit the body -bacteria need large amounts of zinc and iron to multiply -during fever, the liver and spleen sequester these nutrients, making them less available, which helps to reduce the bacterial population
Which of the following is not a mechanism for the development of autoimmune disorders? -exposure of previously "hidden" self-antigens to the adaptive immune system -a second exposure to an allergen -mutation followed by the appearance of membrane proteins not previously present -cross-reaction of antibodies formed against foreign antigens with self-antigens
a second exposure to an allergen
Which of the following is not a method by which antibodies work? -neutralizing antigen -activating cytokines -enhancing phagocytosis -agglutinating and precipitating antigen
activating cytokines
Select the correct statement about active and passive immunity:-immunological memory is established by passive immunization -a vaccination is an example of the introduction of passive immunity into the body -the antibodies utilized in active immunity are acquired from another organism -active and passive humoral immunity are both mechanisms of adaptive immunity that use antibodies
active and passive humoral immunity are both mechanisms of adaptive immunity that use antibodies
Which of the following statements is a false or incorrect statement? -the lymphoid organs where lymphocytes become immunocompetent are called primary lymph organs. All other lymphoid organs are referred to as secondary lymphoid organs -it is our genes, not antigens, that determine what specific foreign substances our immune system will be able to recognize and resist -after becoming immunocompetent, the naive T cells and B cells are exported to the bone marrow where the encounters with antigens occur -T cells and B cells become fully immunocompetent when they bind with recognized antigens
after becoming immunocompetent, the naive T cells and B cells are exported to the bone marrow where the encounters with antigens occur
Which of the following would be classified as a delayed hypersensitivity reaction? -immune complex hypersensitivity -anaphylaxis -cytotoxic hypersensitivity -allergic contact dermatitis
allergic contact dermatitis
In clonal selection of B cells, which substance is responsible for determining which cells will eventually become cloned? -antigen -interferon -antibody -complement
antigen
Which of the following is not a type of T cell? -cytotoxic -antigenic -helper -regulatory
antigenic
Which of the statements below does not describe antigens? -antigens exhibit immunogenicity and reactivity -antigens only come from microbes -the parts of antigen molecules that initiate immune responses are called epitopes or antigenic determinants -antigens can include proteins, nucleic acids, lipoproteins, glycoproteins, and certain large polysaccharides
antigens only come from microbes
Cytotoxic T cells:-are the only T cells that can directly attack and kill other cells -require the double recognition signal of I MHC plus II MHC on the target cell in order to function -function mainly to stimulate the proliferation of other T cell populations -self-destruct once the antigen has been neutralized
are the only T cells that can directly attack and kill other cells
When the white blood cell count is depressed, the classic signs of infection such as redness, heat, and swelling are not manifested. In this case, the nurse should avoid administering aspirin. Explain why.
aspirin would disguise a fever that would indicate infection
B lymphocytes develop immunocompetence in the:-thymus -spleen -bone marrow -lymph nodes
bone marrow
Select the correct statement about antigens: -"self-antigens" is another name for incomplete antigens -the largest type of antigen is called a hapten -only small antigens exhibit reactivity -one antigen may have many different antigenic determinants and may therefore cause the formation of more than one antibody
one antigen may have many different antigenic determinants and may therefore cause the formation of more than one antibody
Complement proteins and antibodies coat a microorganism and provide binding sites, enabling macrophages and neutrophils to phagocytize the organism. This phenomenon is termed:-diapedesis -agglutination -opsonization -chemotaxis
opsonization
____ determine(s) what specific foreign substances our adaptive immune system will be able to recognize and resist:-the type of antigen -memory cell production -enzymes present at the time of the invasion -our genes
our genes
Which of the following is associated with passive immunity? -exposure to an antigen -infusion of weakened viruses -passage of IgG antibodies from a pregnant mother to her fetus -booster shot of vaccine
passage of IgG antibodies from a pregnant mother to her fetus
Harmful or disease-causing microorganisms are called ____.
pathogens
Which of the following does not respond to cell-mediated immunity? -intracellular pathogens that reside within host cells -some cancer cells -foreign tissue transplants -pathogens in the CNS
pathogens in the CNS
Which of the following is a part of the second line of defense against microorganisms? -keratin -cilia -gastric juice -phagocytes
phagocytes
Innate immune system defenses include:-B cells -T cells -plasma cells -phagocytosis
phagocytosis
B cells respond to the initial antigen challenge by:-reducing its size -immediately producing antigen-specific antibodies -forming of a large number of cells that are unlike the original B cell -producing progeny cells that include plasma cells and memory cells
producing progeny cells that include plasma cells and memory cells
Fever:-is a higher-than-normal body temperature that is always dangerous -decreases the metabolic rate of the body to conserve energy -production is regulated by chemicals that reset the body's thermostat to a higher setting -causes the liver to release large amounts of iron, which seems to inhibit bacterial replication
production is regulated by chemicals that reset the body's thermostat to a higher setting