Chapter 24 Review Questions

Where do blood cells come from and where do they develop?

Come from stem cells and develop in bone marrow

What is autoimmune disease? Give examples.

result when our bodies lose tolerance and thus make antibodies against self antigens. Occur when T and B cells are activated to produce immune reactions against self-proteins and result in host tissue damage. Type I diabetes

four types of hypersensitivity reactions giving examples.

Give an example of Type II hypersensitivity penicillin, drug reactions, juvenile diabetes Give an example of Type I hypersensitivity bee sting, hay fever Give an example of Type III hypersensitivity Lupus, rheumatoid arthritis, blood transfusion problems Give an example of Type IV hypersensitivity nickel allergies, poison ivy, contact dermatitis, tuberculin test

Type 1 Hypersensitivity

Happens immediately 1. Constant region of an IgE antibody binds to mast cells instead of the variable region 2. Causes mast cells to degranulate and give off histamines, serotonins, etc. causing vasodilation, redness, runny nose, etc. 3. each exposure is worse and can lead to anaphylactic shock

How is innate immunity different from acquired or adaptive immunity?

Innate: born with it, nonspecific, intact skin, mucus, phagocytes etc. does not require previous exposure to a pathogen or its products Acquired/Adaptive: specific mechanisms of the B cells (humoral immunity) and T cells (cell mediated immunity) in response to antigens associated with pathogens, dependent on previous exposure to the pathogen or its products

What are examples of lymphatic tissue and what is its function?

MALT is a type of lymphatic tissue as is your spleen and lymph nodes.

What is a MHC and where are they found?

Major histocompatibility complex; antigens or proteins found on cells, function as antigen presenting molecules surface of nucleated cells

Explain the primary and secondary antibody response. What type of cells is responsible for each of these responses?

Primar Antibody Response: antigen-stimulated B cells multiply and differentiate to form antibody-secreting plasma cells and memory cells Secondary Antibody Respnse: memory B cells generated may live for years and quickly transform into antibody secreting cells

What are some of the different types of vaccines?

Recombinant-vector vaccines (e.g., rabies vaccine) Recombinant-antigen vaccines (e.g., hepatitis B vaccine) DNA vaccines: based on expression of cloned genes in host cells

How are T-helper cells different from cytotoxic T-cells?

T helper cells: interact with antigen presenting cells and produce cytokines to promote immune reactions, CD4 cytotoxic T cells: kill antigen presenting cells directly, lyses them, CD8

Where does the antibody bind to an antigen?

the epitope or antigenic determinant binds to the T cell receptor (TCR) on a T cell surface

What does a superantigen do?

are a class of antigens that cause non-specific activation of T-cells resulting in polyclonal T cell activation and massive cytokine release. SAgs are produced by some pathogenic viruses and bacteria most likely as a defense mechanism against the immune system.

How is cell mediated immunity different from antibody-mediated immunity? What cells are responsible for each?

cell mediated: antigen-presenting cells such as the phagocytes in innate immunity ingest, degrade and process antigens. They then present antigens to T cells that activate the adaptive immune response. antibody-mediated: Antibody on B cells binds to a pathogen. The B cell ingest, degrades and processes the pathogen. The B cell presents pathogen antigen to a helper T cell, activating it to produce cytokines that in turn influence the B cell to develop into a plasma cell which produces antibodies

What are cytokines?

chemicals that cells use to talk to each other; produced by T helper cells in response to APCs to alert other cytotoxic cells and B cells to begin the immune response. Examples: histamines, prostaglandins

TYpe 2 Hypersensitivity

cytotoxic Takes hours to develop and get worse with each exposure Example: penicillin hapten, first time use won't generate an allergic reaction, but subsequent times will. Bind to serum proteins and eventually cause rashes and breathing problems

Type 4 Hypersensitivty

delayed type hypersensitivity, mediated by T cells. develop over days following exposure to an antigen,

Type 3 Hypersensitivity

involves circulating immune complexes (antigen-antibody reactions) that lodge in joints and kidneys. This can cause problems in blood transfusions and block capillary beds

Where does the lymphatic system empty into the circulatory system?

left subclavian vein

How do vaccines work?

vaccines are just antigens that generate an immune response, creates artificial active immunity

What is an immune deficiency? Give examples.

when an individual is immunocompromised due to genetic defects or infection with HIV Ex: AIDS

Describe the inflammation process and what are the characteristics of inflammation?

1. Damaged cells secrete histamines, prostaglandins and leukotrienes that cause vasodilation and leaky capillaries 2. Neutrophils attracted to infection site by interleukins secreted by leukocytes 3. Margination: phagocytes stick to walls of blood vessels 4. Emigration: squeeze through gaps in cells 5. Neutrophils release chemokines to recruit macrophages by guiding them alone a chemokine gradient to commence phagocytosis 6. Phagocytes die, forming pus and blood clots to seal off site of injury 7. increase delivery of nutrients and oxygen from vasodilation aids in tissue repair redness pain heat swelling sometimes loss of function

How is active immunity different from passive immunity? Natural vs active? Give examples.

Active: refers to when body makes antibody, exposure to an antigen, immunity achieved by injecting antigen or through infection, specific response made by individual achieving immunity, immune system activated by antigen, immune memory in effect, long term, stimulation of memory cells, immune state develops over a period of weeks Passive: refers to antibody, no exposure to antigen, immunity achieved by injecting antibodies or antigen-reactive T cells, specific immune response made by the donor of antibodies or T cells, no immune system activation, no immune memory, short term, immunity develops immediately

What is an antigen presenting cell?

An antigen-presenting cell (APC) or accessory cell is a cell that displays foreign antigens complexed with major histocompatibility complexes (MHCs) on their surfaces; this process is known as antigen presentation. T-cells may recognize these complexes using their T-cell receptors (TCRs).

What are an antigen and an antibody? How are they similar and different?

Antigen: protein from a pathogen that causes an immune response Antibody: soluble proteins made by B cells in response to exposure to non self antigens, displayed on B cell surface to directly interact with antigens Similar: both proteins

What is an antitoxin and how does it work?

Artificial passive immunity The antibody in the antitoxin binds to the toxin and blocks it from binding to the host cell and causing damage

How is blood different from lymph?

Blood: has RBCs, pumped through body via heart, composed of plasma and cells Lymph: no RBCs, no pump, moved through body via muscle movement, contains phagocytes and lymphocytes

Why are booster shots important?

Boosters cause a secondary response, creating a higher antibody titer and long term immunity from the circulation of IgG