Innate & Adaptive Immunity (Exam III) Flashcards
Totality of all our host defense mechanisms
Immune system
Component of immune system we are born with, genetically predetermined
Innate immune system
The nonspecific component of the immune system
Innate immune system
Elements of the innate immune system include (3)
1- mucous secretions
2- complement proteins
3- WBCs (specifically neutrophils, macrophages and dendritic cells)
What specific WBCs are involved in the innate immune system (3)
1- dendritic cells
2- neutrophils
3- macrophages
Component of the immune system that develops a specific targeted response to an antigen or pathogen
Adaptive immune system
Components of the adaptive immune system include (2)
1- B cells
2- T cells
In addition to the B cells and T cells of the adaptive immune system there is also a small number of genetically encoded proteins called antibody genes that produce
Antibodies
Antibodies are capable of recognizing and destroying specific
Antigens
What are some of the numerous tissues involved in the immune system
Lymphoid tissues, bone marrow, kidney, spleen, intestines
All of the cellular elements of our blood and immune system arise from ______ in the bone marrow
Pluripotent stem cells
What are some causes of disease in human
DNA viruses, RNA viruses and bacterial infections, fungal infection, Protozoa infection, worms
The early phase of the immune response is dependent on
Innate immunity
During the early phase of immune response, there are a variety of innate resistance mechanisms used to
Recognize and respond to the pathogen
What type of receptors does the innate immune system use?
Invariant receptors
What receptors recognize common features that are present on mostly all pathogens
Invariant receptors
Where and when is the innate immune system present
All individuals all of the time
The thing that distinguishes the innate immune system from the adaptive immune system is that the innate immune system
Does not increase its responsiveness with increased exposure
The innate immune system is able to distinguish between a group of related pathogens but does not develop a specific response to
Individual pathogens
What is the adaptive immune system responding to and by what
Responding to the antigen by antigen-specific lymphocytes
The adaptive immune system involves the development of what type of memory
Immunological
Adaptive immune response involve ______ of lymphocytes
Clonal selection
What is another name for adaptive immune response
Acquired immune response
Lifelong protective immunity to reinfection by the same pathogen
Immunological memory
In innate immunity, an immediate response occurs within
4-6 hours
The first step of innate immunity in its immediate response is categorized as
Infection
In the immediate steps of innate immunity the infection is recognized by (2)
1- preformed effectors
2- broadly specific effectors
The final step in in the immediate actions of innate immunity
The removal of the infectious agent
If the pathogen is not removed in the immediate steps of innate immunity, the response will extend to
Early induced innate response
The early induced innate response occurs between
4-96 hours
In the early induced innate response, the infection is recognized within the infection
Microbial-associated molecular patterns
In the steps of early induced innate response, once the infections microbial-associated molecular patterns have been recognized, what will occur (2)
Inflammation recruitment and activation of effector cells
If the early induced innate response does not result in removal of the infectious agent the immune response will proceed on to the
Adaptive immune response
The adaptive immune response occurs after
96 hours
In the adaptive immune response phase, we have the transport of an antigen to
Lymphoid organs
In adaptive immune response phase, following the transport of the antigen to lymphoid organs, what occurs
Recognition by naive B and T cells
In the adaptive immune response phase, once the antigen has been recognized by naive B and T cells what occurs
Clonal expansion and differentiation to effector cells
Major cells of the innate immune system (5)
1- macrophages
2- granulocytes
3- mast cells
4- dendritic cells
5- natural killer cells
Major cells of the adaptive immune system (4)
1- B cells
2- T cells
3- Natural killer cells
4- plasma cells
What type of cell produces antibodies and secretes them at large concentrations
Plasma cells
The innate immune system includes cells from what lineage
Myeloid
In the intial phase of infection triggering an immune response, bacteria trigger
Macrophages to release cytokines and chemokines
What two things are accomplished by the release of cytokines and chemokines in an immune response
- Increase in vascular dilation
- Increase in vascular permeability
Th increase in vascular dilation in an immune response leads to
Redness
The increase of vascular permeability in an immune response leads to
Swelling
Why does the increase in vascular permeability cause swelling
Because you are moving fluid from blood/lymph into the tissue
In an immune response, the increase in vascular dilation and permeability triggers ___ to transmigrate across epithelial cell layer
Neutrophils
The neutrophils that transmigrate across the epithelial cell in an immune response function to
Gobble up the bacteria
In a immune response, the macrophages dendritic cells that participate previously resided where
Peripheral tissue
If the infection is not taken care of by the neutrophils, then what is the next cell to participate
Immature dendritic cells
The immature dendritic cells called in after the neutrophils fail to control the infection, come from
Peripheral tissue
The immature dendritic cells that reside in our peripheral tissue will grab ahold and _____ the invading microorganism
Ingest
In an immune response, the immature dendritic cells migrate out of the _____ and via ____ eventually reach ____
Peripheral tissue
Lymphatic vessels
Lymph nodes
Once the immature dendritic cells make it to the lymph nodes in an immune response, they will interact with _____ leading to ____
Naive T cells
Activation of T cells
In an immune response, once the naive T cells have been activated by mature dendritic cells in the lymph node, activation of ____ occurs
B cells
In an immune response, the activation of B cells leads to
Immune antibody response
What must infectious agent overcome in order to establish an inflection
Innate host defenses
Because of the innate host defenses, infectious disease is generally
Quite infrequent
What is forms first barrier again most most microorganisms
Epithelial (mucosal) surfaces
The epithelial (mucosal) surfaces that act as the first barrier against microorganisms have _______ if injured
Rapid repair mechanisms
What type of cells provide a physical Ariel and innate immunity
Mucosal epithelial cells
What type of cell secretes mucous that forms a dense protective covering for the entire epithelium (commonly observed in GI system)
Goblet cells
Mechanism in the GI tract that moves food and potential pathogens
Peristalsis
In the upper respiratory tract, what cells capture inhaled pathogenic particles and expel them through a beating motion
Ciliated epithelial cells
Cells that produce anti-microbial peptides, commonly found in saliva
Paneth cells
Intraepithelial lymphocytes contain various (type of cell)
T-cells
GALT
Gut-associated lymphatic tissue
Describe the mucosal tissues’ exposure to microbe and frequency
Constantly exposed and frequently infected
Mucosal immunity is _____ rather than ____
Proactive; reactive
The mucosal immunity is constantly making _____ immune response against microbes
Adaptive
When we talk about mucosal immunity making adaptive immune responses what type of immunity is ultimately involved in
Innate immunity
What does the mucosal immunity generally not active
Inflammation
In the gut, inflammation would likely _____ the infection rather than clear it out
Exacerbate
Mucosal immune responses do what to the tissue involved
Little damage
Because the mucosal tissues are constantly active in immune response it contributes to
Gut epithelial cells rapid replacement/turnover
What are the types of mucosal surfaces
Type I
Type II
Mucosal surface type covered by simple epithelium
Type I
Mucosal surface type that expresses a simple polymeric Ig receptor (pIgR) that allows dimeric IgA to access the lumen
Type I
In Type I mucosal surface, the expression of pIgR allows for _____ to access ____
Dimeric IgA
Lumen
Examples of where you would find Type I mucosal surface
Intestine
Lungs
Uterus
Mucosal surface type covered by a stratified squamous epithelium
Type II
Mucosal surface type that provides physical protective barrier activities that are important to the host
Type II
Examples of where you would find Type II mucosal surface
Oral cavity
Vaginal cavity
Name the following types of epithelial tissue
1- simple squamous epithelium
2- stratified squamous epithelium
3- simple cuboidal epithelium
4- stratified cuboidal epithelium
5- simple columnar epithelium
6- stratified columnar epithelium
7- pseudostratified columnar epithelium
1- simple squamous epithelium
2- stratified squamous epithelium
3- simple cuboidal epithelium
4- stratified cuboidal epithelium
5- simple columnar epithelium
6- stratified columnar epithelium
7- psuedostratified cuboidal epithelium
What are the modes of transmission for airway mucosal surfaces (2)
Inhaled droplets
Spores
What is the mode of transmission into mucosal surface of the gastrointestinal tract
Contaminated water or food
What is the mode of transmission of the mucosal surfaces of the reproductive tract
Physical contact
Routes of entry for infection of the external epithelia (3)
1- external surface
2- wounds and abrasions
3- insect bites
The mode of transmission into the the external surface of the external epithelia
Physical contact
The mode of transmission info wounds and abrasions of the external epithelia (3)
1- minor skin abrasions
2- puncture wounds
3- handling infected animals
The mode of transmission for insect bites on the external epithelial include (2)
1- mosquito bites
2- deer tick nites
What can we categorize the modes of first line defense as (3)
1- mechanical
2- chemical
3- microbiological
In the skin, gut, lungs, and eyes/nose what is a common mechanical defense against microbes
Epithelial cells joined by tight junctions
Longitudinal flow of air or fluid is a mechanical defense of
Skin and gut
Movement of mucus by cilia is a mechanical defense of the
Lungs
Tears and nasal cilia are a mechanical defense used by
Eyes and nose
If we are talking about the cilia functioning in the immune system, what type of defense is this
Mechanical
Fatty acids, low pH, Enzymes (pepsin and lysozyme) and antibacterial peptides are all forms of what type of defense
Chemical
When the gut and skin display normal flora this is an example of
Microbiological defense
When the dendritic cells migrate to the lymph nodes this signals
Adaptive immunity
Specific antibodies, T-cell dependent macrophage activation and cytotoxic T cells are all component of what response
Adaptive immune response
How do phagocytes deal with bacterial agents? (6)
1- acidification
2- toxic oxygen derived products
3- toxic nitrogen oxides
4- antimicrobial peptides
5- enzymes
6- competitors
The acidification mechanism released by phagocytes involves a pH of ____ and is considered ______
3.5-4.0
Bacteriostatic/bactericidal
Superoxide, hydrogen peroxide, singlet oxygen, hydroxyl radical and hypophalite are all _____ produced or released by phagocytes
Toxic oxygen-derived products
The specific toxic nitrogen oxide that is produced or released by phagocytes is
Nitric oxide (NO)
Antimicrobial peptides produced or released by phagocytes include
Defensins
Cationic proteins
What enzyme produced or released by phagocytes dissolves the cell walls of sone gram + bacteria
Lysozyme
What enzyme produced or released by phagocytes further digests bacteria
Acid hydrolases
What two competitors can phagocytes produce or release
Lactoferrin and vitamin B12-binding protein
What type of columnar epithelial cells layer is GI tract is made up of
Villus type
Interspersed between the villus type epithelial cells making up the GI tract are ____ cells
Paneth cells
The Paneth cells produce
Alpha and beta types of defensins
The alpha and beta defensins produce by Paneth cells are _____ in nature
Antibacterial
The gut contains ____ that secrete mucous
Goblet cells
In the large intestine you have both an outer and inner
Mucous layer
What are defensins (produced by Paneth cells)
Antimicrobial peptides
Bacteria in the large intestine tend to reside in
Describe this layer
The outer mucosal layer
Looser layer
If the antigen does get into contact with the epithelial layer of the intestine and manages to somehow get inside that will trigger the innate immune system and where this triggering event occurs is referred to as
Inductive site
Where an initial immune triggering event occurs
Inductive site
Important cell of the gut involved with the inductive site
M cell
What is the site where antigen clearance is finished
Effector site
The most important part of a lymph node
Germinal center
What takes place inside the germinal center of the lymph node
Clonal selection and expansion
If a B cell moves into a germinal center of a lymph node it will undergo clonal expansion what is it doing
Dividing a lot
In the process of a B cell undergoing clonal expansion in a germinal center of a lymph node, what is occurring
Somatic hypermutation
What expands the repertoire of potential antibodies that can recognize the antigen
Somatic hypermutation
After somatic hypermutation occurs in the germinal center _____ takes place
Selection
After selection in the germinal center takes place you will ideally have ____ cells produced to secrete ___
Plasma cells
Antibody
Selection
Somatic hypermutation
Differentiation
Class switching
Clonal expansion
If a naive B cell is to travel into the germinal center of a lymph node what order of events take place to ultimately produce plasma cells an memory B cells
1- clonal expansion
2- somatic hypermutation
3- selection
4- class switching
5- differentiation
What do we ultimately want to come out of the germinal center or the lymph node
Memory B cells
Plasma cells
Clonal expansion starts with a single _____ that gives rise to a large number of ____ each with a different specificity
Proginetior cell
Lymphocytes
In clonal expansion, what give the lymphocytes derived from the progenitor cells different specificity
Receptors
(During clonal expansion) The lymphocytes with their receptors that recognize self antigen or are that potentially self reactive get
Removed/destroyed
(In clonal expansion) what removes the potentially self-reactive immature lymphocytes
Clonal deletion
The lymphocytes with non-self receptors will continue on to form
A pool of mature but naive lymphocytes
In clonal expansion, the pool of mature but naive lymphocytes remain in this pool until
A foreign antigen is presented
In clonal expansion, when a foreign antigen is presented to the pool of mature but naive lymphocytes it will bind to a specific receptor on a particular lymphocyte resulting in
Proliferation and differentiation of activated specific lymphocytes
During clonal expansion, the proliferation and differentiation of an activated specific lymphocyte will form a
Clone of effector cells
In clonal expansion what ultimately eliminates the antigen
Effector cells
For each pathogen we encounter we will develop
Specific antibodies to that pathogen
Structure of antibody:
Two light chains
One heavy chain
In an antibody what connects the light and heavy chains
Cysteine bridges
What region is found in the heavy chain of an antibody
Constant region
What region is found in the light chain of antibodies
Variable region
The variable region in antibodies is the
Antigen binding site
The constant region has what function
Effector function
The effector function of the constant region on an antibody utilizes mechanism that are
Constant to all antibodies
What is the name of an activated B cell
Plasma cell
What type of cell secretes antibodies
Activated B cell (plasma cell)
In addition to antibodies, T cell receptors have both
Variable and constant regions
The diversity of antibodies is done through a process called
Somatic gene-segment rearrangements
The light chain of antibodies contain what two components
Variable region
Joining segment
What are the gene clusters on light chains of antibodies
Kappa (Cs2)
Lambda (Cs22)
How many heavy genes are there on antibodies and what chromosome are they located on
5
Cs14
How many total different light chains on antibodies
290
How many heavy chain variable regions
13,800
How many total binding specificities of antibodies
4,002,000
In addition to the numerous total binding specificities antibodies can also display ____ changes between the different gene segments to increase the specificity of the variable regions
Single nucleotide changes
Antibodies recognize
Surface epitopes
Specific regions within antigens that antigen receptors bind
Epitopes
T cells receptors recognize
Buried epitopes
In order for a T cell receptor to recognize buried epitopes, the antigen must first be
Broken down into peptide fragments
When the antigen containing the buried epitope is broken down into peptide fragments, the epitope peptide binds to a self molecules called
MHC molecule
When T cell binds to a buried epitope it is ultimately binding to
A complex of MHC molecule and epitope + epitope peptide
What molecule presents the previously buried epitope peptide on its surface to be further bound by a T cell receptor
MHC molecule
What are the three ways antibodies participate in host defense
- Cells with nonspecific receptors recognize toxin
- Bacteria in Extracellular spaces picked up by macrophages
- Bacteria in plasma
The nonspecific receptors of cells that pick up bacterial toxins function the process of ________ by nonspecific antibodies
Neutralization
If the bacteria exists in the extracellular space and is picked up by the macrophage what process will occur
Opsonization
If bacteria gets into the bloodstrea/plasma then what processes will occur
Complement activation and clearance
Neutralization, opsonization and complement activation all ultimately result in
Ingestion of the bacteria
Large locus of DNA that encodes genes for cell surface receptors that are essential for the adaptive immune response
MHC molecules
What type of response are MHC molecules essential for
Adaptive immune response
Class of MHC molecules that collect peptides derived from proteins synthesized in the cytosol from viral infections and display those peptides on the cell surface
MHC I
Class of molecules that bind peptides derived from proteins in intracellular vesicles and display those on cell surface
MHC II
What MHC class has a single transmembrane-spanning domain
MHC I
What class of MHC molecules have two membrane-spanning domains
MHC II
Where do both the MHC I and II molecules display peptide
On their surface
cytotoxic T cells recognize complex of viral peptide with ______ and kills infected cell
MHC I
Viral infections deal with what MHC class, while anything else deals with what MHC class
Viral- MHC I
Anything else- MHC II
MHC I engages what type of cell
MHC II engages what type of cells
MHC I - cytotoxic T cell
MHC II - helper T cells
What are our antigen-presenting cells
Macrophages, dendritic cells, B cells
