Ch. 15

What is the purpose of Class I MHC, Class II MHC, and Class III MHC?

Class 1 MCH- code for self molecules Class 2 MCH- immune function Class 3 MCH- complement system

Which of the following correctly describes Staphylococcus aureus?

Gram positive cocci arranged in clusters

Why are CD4 cell counts an important measure in determining the progression of HIV disease to AIDS?

Helper T cells which posses the CD4 makers are important in the activation or efficiency of both adaptive and innate defenses.

What is the purpose of each of the 5 types of Ig - IgG? IgM? IgA? IgD? IgE?

IgG- most common; crosses placenta; presence indicates a previous infection IgM- first to appear; pentamer; higher than normal levels indicate a current infection IgA- localized protection on mucosa; prevents attachment of pathogens; respiratory infections; colostrum- intestinal illness IgD- Presence on B cells functions in initiation of immune response IgE- allergic reactions; possible lysis of parasitic worms.

Early in the primary response, most of the antibodies are the _______ type.

IgM

_______ with antigen fragments displayed on their surfaces are known as antigen-presenting cells (APCs)

Macrophages

MHC-II molecules are located on what types of cells?

Macrophages, dendritic cells and B cells

A toxoid would best be described as an example of which type of vaccine?

subunit vaccine

What are the functions of TH1, TH2, TH17, TREG, and TC?

TH1- activate phagocytosis TH2- activate B-cells by producing interleukins TREG- non antigen specific NK cells TC-release perforin granzyme TH17- secrete interleukin-17

An attenuated vaccine usually provides better immunity than a killed or inactivated one.

TRUE

Which of the following cells are needed for most B cells to become functional?

t helper cells

What interaction is involved in the stimulation of a helper T cell?

the interaction of the T cell receptor with processed antigen and the binding of CD4 to the MCH II molecule

In creating a recombinant vaccine, a gene for an antigen can be spliced into a plasmid. What happens next?

the plasmid is placed into a host cell, such as yeast and the yeast will produce large quantities of the antigen

Which of the following is correct regarding antibodies?

they are proteins

When first administered to a naïve individual (has not been exposed to measles virus), the measles vaccine will stimulate

a primary response

An individual successfully recovered from measles as a child. Now 35 years old, her toddler has the infection. What immune response is occurring in the woman's body at this time?

a secondary response

Antibodies are produced by which line of defense?

third

Which process involves a more rapid synthesis and greatly increased titer of antibody when the immune system is subsequently exposed to the same antigen?

anamnestic response

A helper T-cell becomes activated by a(n) ______.

antigen-presenting cell

Which of the following is a term that refers to a gamma globulin that can neutralize virulence factors secreted by Staphylococcus or Streptococcus strains, as in the case of TSS?

antitoxin

Characteristics of antigens include

are made up of many antigenic determinants (epitopes)

Live chickenpox virus can be used in a(n) _______.

attenuated vaccine

Antibiotics were used for treatment because Staphylococcus aureus is a ______.

bacterium

Superantigens

bind without antigen specificity to the outer portion of portion of T helper cells and antigen presenting cells (APCs)

Based upon the epidemiological evidence, the mode of transmission in this case was

direct contact

Epidemiologists determined that this outbreak could have been avoided if

everyone had been adequately vaccinated against measles

Cytotoxic T-cells directly kill the viruses found inside of infected cells.

false

Each antigen has one epitope.

false

Helper T-cells interact with Class I major histocompatibility complex (MHC) proteins.

false

In a subunit vaccine, the subunit must come from the outer surface of the pathogen

false

One plasma cell will secrete antibodies of various classes but the antibodies will all have different specificity.

false

True or False: One antibody can bind multiple types of antigens.

false

True or False: The actual bacterium causes the development of the symptoms seen in TSS.

false

When activated by antigen-presenting cells, helper T-cells release what cytokine that activates B-cells and cytotoxic T-cells?

interleukin-2

Cytotoxic T-cells know that a cell is infected because

it has antigen from the disease-causing microbe on its surface

What is the purpose of booster shots?

to stimulate a secondary or anamestic response

A helper T-cell must be activated before it can stimulate a B-cell to produce antibody

true

Both antigen-presenting cells and B-cells have class II MHC receptors on their surface

true

MHC-I molecules normally display "self" proteins, those that are normally produced by a cell.

true

Plasma cells are B cells that produce antibodies.

true

Proteins generally are T-cell dependent antigens.

true

Self proteins of infected cells are not recognized by cytotoxic T-cells.

true

True or False: An effective measles virus vaccine exists today.

true

Vaccinations depend on the anamnestic response to successfully protect a person from infection.

true

Cytotoxic T-cells recognize

viral antigens and class I MHC

Measles is caused by a ______.

virus

CD8 markers bind to MHC class ___ molecules.

1

In the case of cancer or viral infection, which MHC class is involved with displaying abnormal proteins to cytotoxic T cells as a signal for destruction?

1

Naturally Acquired

1. Active through infection 2. passive through antibodies to the newborn

artificially acquired

1. Active through vaccination 2. passive through antibodies by immunoglobulin injections

Name the 5 ways that antibodies tag antigens

1. Osponization- coating antigen with antibody 2. Agglutination-phagocytosis by grouping together antigens 3. Neutralization- blocks adhesion 4.Anti toxin- blocks toxin 5. interaction with complement- cytolysis MAC (membrane attack complex)

Helper T cells require antigen processing and presentation by MHC-___ molecules.

2

B-cells

mature in bone marrow Intercellular; bacteria

T-cells

mature in the thymus intracellular; virus

The immune system responds more swiftly by making antibodies to an antigen after the first exposure because

memory B-cells are produced during the first response

B cells differentiate into plasma cells and _______.

memory cells

MHC-I molecules are located on what types of cells?

All nucleated cells

An antigen-presenting cell presents antigen to a helper T-cell

on its surface using a class II MHC

Which of the following statements characterizes clonal selection in the process of antibody production?

one B cell type is selected to produce one type of antibody

Cytotoxic T-cells produce

perforin, which makes holes in cell membrane of infected cell

B-cells differentiate into ______, which make antibodies.

plasma cells

In the bloodstream, bacterial antigens will first bind to antibodies presented on _______.

B-cells