Immunity & infection, packet #1 Flashcards
Bacteria that is beneficial and does no harm to humans are called?
Communal bacteria
Bacteria that can cause infections and disease are called?
Pathogenic bacteria
The immune system protects from _______ and also ________.
pathogens
cancer
The first line of the immune system defense are made up of?
Physical and chemicals barriers
What is the largest organ in the body?
Skin
All body cavities and passages that expose to the external environment are lined with _______ __________.
Mucous membranes
Where would you find mucous membranes?
Mouth, nostrils, eyelids, bronchioles, vagina, and other organs of the respiratory, digestive, and urogenital tracts.
What tissue makes up the skin and mocous membranes?
Epithelial tissue
What is the configuration of the layout for epithelial tissue in skin and mucous membranes?
One or more layers of closely packed cells with almost no space in-between the cells.
The fluids that cover the skin and the mucous membrane are filled with what?
Enzymes.
The respiratory tract has an added defense mechanism on the cells that are lined with mucous mombranes. This addition is called what?
Cilia
If particles make it past the cilia, into the respiratory organs, what defense mechanism will be used to expel it?
A cough
What two systems incorporate to make up the immune system?
The innate and adaptive immune systems.
Which immune system are you born with?
Innate immune system
How does the adaptive immune system aquire its ability to help the immune system?
Over time with exposure to microorganisms
Which immune system will launch a nonspecific defense, every time, all the time?
The innate immune system.
Which immune system will launch a very specific type of defense?
Adaptive immune system.
How does the specific mechanism of the adaptive immune system work?
Like a lock and key.
For the complete elimination of a pathogen, what must occur?
The coordinated activities of both the innate and adaptive immune systems
The immune system works through the actions of different types of?
WBC’s
WBC’s are continuously produced where?
In the bone marrow.
What is a key feature of a WBC?
It can distinguish foreign cells from host cells.
What can’t the cells of the innate immune system develop?
A memory of past pathogens.
What are the 5 cells of the innate immune system?
Neutrophils, eosinophils, macrophages, natural killer cells, and dendritic cells.
Which innate system cell travels to a site of infection via the blood stream to attack and ingest pathogens?
Neutrophils.
Which innate system cell occur in mucosal tissues and provide innate immunity to certain microbes?
Eosinophils
Which innate system cells act as scavengers, devouring pathogens and worn out cells?
Macrophages
Which innate system cell destroys virus infected host cells and host cells that have turned cancerous?
Natural killer cells
Which innate system cell resides in tissues, engulfs pathogens and activates lymphocytes?
Dendritic cells
What are the WBC’s of the adaptive immune system called?
Lymphocytes
The two main lymphocytes are called?
T cells and B cells
How do the T and B cells of the adaptive immune system differ from those of the innate immune system?
They are capable of exquisite specificity and of immunological memory.
Which markers trigger an immune response?
nonself markers
Nonself markers that cause an immune response are known as?
Antigens
What are specialized proteins that circulate in the bloodstream and are present in almost all body fluids?
Antibodies
Who produce antibodies?
WBC’s
Antibodies have complementary markers on their surfaces that work with antigen markers in what fashion?
Lock and key
Complementary markers allow antibodies to do what?
Recognize and neutralize specific microbes
When an antibody locks with a specific antigen, what two things can occur?
The antibody will either (1) neutraize it or (2) flag it for attack by the immune system.
When a T or B cell encounters an antigen for which it is specific to, what will occur?
The cell will proliferate, producing more lymphocytes “daughter cells” which are specific for that antigen.
When new lymphocyte “daughter cells” are created what will they do next?
They will differential into cells with specific immune functions and attack the invading pathogen for which it had the antigen made.
B cell “daughter cells” become what specific cells and what is their immune function?
They become plasma cells and secrete antibodies verse a specific antigen or they can also become memory B cells which retain response ability for months or years later.
T cell “daughter cells” become what specific cells?
They can become 4 kinds of cells
1) T cells
2) Killer T cells
3) Suppressor T cells (regulatory)
4) Memory T cells
The body is injured or infected, specialized cells in the area will release what substance?
Histamine.
Histamine will have what effect in the area of infection or injury?
It will cause inflammation, blood vessels will dilate and the fluid in them will flow out of the capillaries and into the interstitial spaces and infected/injured tissue.
The effect of histamine will cause what kind of reaction in the areas of infection/injury?
Increased heat, swelling, and redness in the area.
The heat/swelling and redness reactoin caused by histamine will attract what to the infection/injury?
WBC’s
The WBC’s that attack an infection will cause what to be created?
Pus
What is pus composed of?
Dead WBC’s and debris resulting from the immune response to the infectious invader.
Name the phases of the immune response.
Recognition, proliferation, elimination, and slowdown.
What cells are drawn to the site of injury and consume the foreign cells?
Dendritic cells
During the recognition phase, what do the dendritic cells do during this phase?
They go to the site of the injury and consume foreign cells. Then they migrate to the nearby lymphoid tissue to turn on T cells by showing the antigen markers of the foreign cells. Then the natural killer cells and other early responders will destroy infected cells.
Which cell is the main player in the start of the proliferation stage?
Helper T cells
During the proliferation phase, what do the helper T cells do?
Helper T cells rapidly stimulate the proliferation of T and B cells.
What are cytokines, where do they come from and what do they do?
They are chemical messengers that are secreted by lymphocytes and other cells within the immune system. Their role is to regulate and coordinate the immune response.
During the elimination phase, what do killer T cells do?
They strike at foreign cells and infected body cells. They identify them by placing antigen markers on their surfaces, punturing cell membrane, sacrificing host cells in order to destroy the foreign organism inside.
What type of immune response is it when killer T cells are activated?
Cell-mediated immune response.
When a cell-mediated immune response occurs, what can you expect?
An amplified inflammatory response for which many more macrophages are recruited to infection site.
During elimination phase, what do B cells do?
They produce large quantities of antibody molecules and distribute into the bloostream and tissues. These antibodies will then bind to the correct antigens, marking them for destruction.
What type of immune response is it when B cells flood the blood and tissue with antibodies?
Antibody-mediated immune response.
What does the antibody-mediated immune response work against and how do they assist in elimination?
They work against bacteria, viruses and other substances outside of the cell and they allow cells of the innate immune system to eliminate the pathogens they just marked.
What is occuring during slowdown?
Regulatory molecules and suppressor T cells inhibit lymphocyte proliferation and induce lymphocyte cell death, causing a slowdown which bring the levels of T and B cells back to “resting” levels.
How does future immunity towards pathogens occur?
During slowdowm, some T and B cells remain in the body, providing memory, where they can initiate a rapid response verses same pathogen in the future.
What must occur for a person to gain immunity to an infection?
They must get infected and survive that infection.
What phase will begin the process of a person gaining immunity towards a specific pathogen?
The elimination phase, when lymphocytes are created, producing memory T and B cells.
What is the immunity term called for a person who just created T or B cells from an infection?
Acquired immunity
How does aquired immunity prevent future illness?
The memory T and B cells recognize the pathogen and initiate an immune response before illness occurs.
The ability of memory lymphocytes to remember previous infections is known as what?
Acquired immunity.
What does the lymphatic system consist of?
The spleen, lymph nodes, and a network of vessels that carry a clear fluid called lymph.
What do lymph nodes do?
The lymph passes through the lymph nodes where a concentration of macrophages and dendritic cells clear the lymph of debris and pathogens.
Which site of the lymphatic system cause activation of T and B cells?
Lymph nodes
When activated, lymph nodes become?
Swollen
Checking for swollen lymph nodes gives clues to a patients medical staff about what?
Possible infection’s location and cause.
What is the basis of immunization?
The ability of the immune system to remember previously encountered organisms and retain its strength against them in the future.
How is a person given immunity?
The immune system is primed with an antigen similar to the pathogen, but not as dangerous. The body responds by creating antibodies, which will prevent infection to the undesired pathogen if ever exposed.
When a patient is primed with an antigen, this is normally referred as?
A vaccine
How are vaccines made?
They are either cultured and attenuated or dead pathogens that still have surface markers.
Vaccines give a patient what kind of immunity?
Active immunity.
What is active immunity?
When a patient produces their own antibodies verses a specific pathogen.
When a vaccine already has the antibodies in it, this gives a patient what kind of defense?
Passive immunity
What is a negative of using passive immunity vaccines?
They are short term and they do not illicit acquired memory for the patient.
What are the concerns people have with vaccines?
Potential shortages and safety. Some wonder if they are worth getting.
What contributes to factors of insufficient vaccine supplies?
Insufficient stockpiles, manufacturing and production problems, and limited number of companies making vaccine. They are expensive to develop and produce and have a low profitability. The flu vaccine changes from year to year thus changing supply problems.
What are the possible side effects of vaccines?
Mild soreness at injection site and possible allergic reation.
Why is universal or near-universal immunization important?
It is necessary to reduce both individual and community risk of communicable diseases.
Why is it not essential that every member in a community be vaccinated?
Because immunizations reduce the prevalence and spread of a disease throughout a community, thus lowering the risk that a disease will get a foothold. This is known as herd immunity.
Why is it bad if parents don’t want to vaccinate their children and would rather rely on herd immunity?
If a large number of people do this it would allow for the foothold, prevalence and spread of a disease in a community. They are undermining the herd immunization.
Can vaccines cause autism?
No
Allergies are a result of?
A hypersensitive and overactive immune system.
What is the substance that provokes allergies?
Allergens
Name the common allergens.
Pollen, animal dander, dust mites, cockroaches, mold mildew, and insect venom.
What are some less common allergens?
Medications, plants, latex, metals and compounds in cosmetics.
Most allergic reactions are due to the production of a special type of antibody known as?
Immunoglobulin E (IgE)
The initial exposure to an allergen causes what chain of events?
A small or little response, followed by the production of allergen specific IgE, which then binds to mast cells.
What is the role of mast cells?
They are part of the immune system, healing process and allergic reations
When IgE binds to a mast cell, what occurs next?
The mast cells release large amounts of histamine and other components into local tissues.
What are the effects of histamine?
Increasing the inflammatory response and stimulating mucus production.
What does histamine do in the nose?
Causes congestion and sneezing.
What does histamine do to the eyes?
Itchiness and tearing.
What does histamine do to the skin?
Redness, itchiness and swelling.
What does histamine do to the intestines?
Bloating and cramping.
What does histamine do to the lungs?
Coughing, wheezing and SOB.
Pertaining to the lungs, in some people, an allergen can trigger what?
Asthma attack
The most serious and rare kind of allergic reaction is?
Anaphylaxis.
What is released that causes anaphylaxis?
Histamine is released thoughout the body.
Why is anaphylaxis life threatening?
It can cause swelling of the throat, extremely low blood pressure, fainting, heart arrhythmia, and seizures
What is the required treatment to stop anaphylaxis?
Epinephrine shot.
What are the 3 general strategies for dealing with allergies?
Avoidance, medication, immunotherapy
Pertaining to dealing with allergies, what does avoidance mean?
Changing ones behavior and/or environment to minimize exposure to allergens.
What medications are there to help deal with allergens and what do they do?
OTC antihistamines (they control symptoms, such as blocked nasal, sinus, or middle ear passages) and
RX corticosteroids via aerosol (which reduce allergy symptoms, increase effectiveness, and help limit systemic absorption and side effects)
What is immunotherapy?
It is a series of slightly increasing dose shots called “allergy shots” that over time help a person become desensitized to a particular allergen.
What is the physical cause of asthma?
Chronic inflammation of the airways and the spasm of the muscles surrounding the airways. The spasm causes constriction and the inflammation causes the airways to secrete extra mucus.