Immuno: Into To Immunity And Inflammation Flashcards
What is immunology?
Science that studies how the body protects itself against pathogens
Different pathogens:
-bacteria
-viruses
-protozoa
-fungi
-parasites
Immunity
The body’s ability to resist or eliminate potentially harmful foreign materials or abnormal cells
Three functions of the immune system:
- Protect from pathogens
- Discriminate between self and non-self cells
- To eliminate abnormal cells
Two types of pathogens:
Intracellular and extracellular
Major histocompatability complex (MHC) is also known as…
Human leukocyte antigens (HLA)
The MHC or HLA function:
-identifies “self” to immune cells
-presents foreign antigens to immune cells
Class I MHC location and function
-All nucleated human cells
-presents processed antigen to cytotoxic CD8+ T cells that target virus infected cells, tumor cells, and transplanted cells
Class II MHC location and function
-located in antigen presenting cells(macrophages, dendritic cells, B cells)
-presents foreign antigens processed antigenic fragments to CD4+ T cells for effective interaction among immune cells
Three R’s of the immune system function
- Recognize the “intruder”
- Respond to eliminate or neutralize the threat
- Remember to enable quicker response in future encounters
Pathogens
Disease-causing microorganism
antigen (Ag)
Foreign proteins that stimulate an immune response
________ are covered with antigens
Microbes
Antibody (Ab)
Immuno-reactive protein made in response to exposure to foreign Ag
Types of Lymphocytes
-B lymphocytes
-T lymphocytes
B lymphocytes
-plasma cells make antibodies specific to each Ag
-termed Ab-mediated immunity
Types of T lymphocytes
-cytotoxic lymphocytes
-T-helper lymphocytes
Cytotoxic lymphocytes
Attack infected/mutant/foreign cells (Tc/CD-8)
T-helper lymphocytes
Regulate immune response (Tc/CD-4)
Phagocytes (wha they are and the two types)
-cells that kills and eat
-macrophages and neutrophils
Macrophages
-antigen presenting cells
-Cells that ingest pathogen adn cellular debris and presents to helper T (Th) cells
-activate specific immunity
Neutrophils
-non-antigen presenting
-ingests protein and cellular debris but does NOT present antigens to Th-cells
Function of macrophages, dendritic cells, and natural killer cells
Phagocytosis
Function of eosinophils
Killing certain parasites involved in allergies
Function of T cells
Cell-mediated immunity
Function of B cells
Humoral immunity
*plasma cells produce antibodies
Function of platelets
Blood clotting
CD4+ TH1-cells activate…
Macrophages and CD8 cells
CD4+ TH2-cells activate…
B cells to produce antibodies
CD8+ T-cells are…
Cytotoxic
General antigen presenting cell (APC) characteristics:
-found in all cells
-present antigen found inside the cell using MHC class 1
-interacts with CD8+ Tcells (cytotoxic T cells)
Professional antigen presenting cell (APC) characteristics:
-found in Bcells, macrophages, and dendritic cells
-present antigens found outside the cell via MHC class II
-interface with CD4+ T cells (helper T cells)
Macrophages are called ______ in liver
Kuppfer cells
Macrophages are called ____________ cells in skin, lymph nodes, conjunctiva, and cornea
Langerhans cells
The body’s defense:
-non-specific barriers
-non-specific cellular
-specific immunity
Non-specific barriers
-1st line of defense
-skin, mucus, HCl
Non-specific cellular
-1st line of defense
-**innate immunity
-phagocytosis, inflammation, complementary proteins, fever
Specific immunity
-2nd line of defense
-**adaptive immunity
-antibodies, B cells, T cells
Innate immune system structural defenses respond to…
Non-specific foreign substances
Innate immunity is the ______ line of defense
First
Inflammation is a…
Non-specific, defensive response to tissue damage
4 hallmarks of inflammation:
- Redness
- Heat
- Swelling
- Pain
Redness, heat, and swelling during inflammation is caused by..
Histamine causing vasodilation and capillary leakage
Pain in inflammation is caused by…
Neural receptor stimulated by Kinins
Five steps to inflammation:
- Initial phagocytosis
- Capillaries dilate and become more permeable
- Foreign matter contained
- More leukocytes ingrate to area
- Leukocytes clear infection
Capillaries dilate and become more permeable due to…
Histamine released from mast cells
Function of inflammations:
- Deliver effector compounds and cells to infection site
- Provide physical barrier to prevent spread of infection to bloodstream
- Promotes repair of injured tissue
Mechanism of compliment proteins:
-Lyse bacteria and some viruses
-initiate inflammation by stimulating histamine release
-chemotaxis
-opsonin
Chemotaxis
Recruit/activate phagocytic cells
Opsonin
Enhances phagocytosis
Mechanism of lactoferrin and transferrin
Compete with bacteria for ion
Mechanism of lysozyme
Breaks down bacterial cell walls
Complement proteins are a group of ______ proteins produced by the ______
About 30, liver
Actions of complement proteins when activated:
- Pokes holes in bacteria via MAC attack
- Stimulate histamine release
- Chemotaxis
- Opsinization
“MAC” stands for:
Membrane attack complex
Histamine release initiates…
Inflammation
Three complement pathways:
- Alternative pathway
- Lectin pathway
- Classical pathway
The pathway(s) apart of innate immunity:
-alternative pathway
-lectin pathway
Pathway(s) part of adaptive immunity:
-classical pathway
All three compliment pathways act on..
C3a or C3b
C3a is involved in…
Inflammation
C3b is involved in….
Opsonization and phagocytosis
C3a is involved in…
Inflammation
C5b combines with ________ and is involved in…
C6-9, lysis of microbe
Primary immune response
-occurs days-weeks after first exposure
-antibody response is not long lived
-illness symptoms occur
-B cells become plasma cells that produce antibodies
-TH cells and Tc involved in cell mediated response
Secondary immune response:
-subsequent exposure that occurs within hours-days
-greater magnitude and more prolonged reponse
-occurs due to memory cells
IgM
Immunoglobulin seen in primary immune response that is slower and weaker
IgG
Immunoglobulin seen in secondary immune response that is stronger and faster
High [ ] of IgG means that..
There has been a previous infection or person has been immunized
Active immunity :
-Long-lasting protection (memory)
-multiple effector mechanisms activated
-lag time
Passive immunity:
-rapid protection
-short duration
In active immunity the individual…
Actively produces their own antibodies and it requires exposure to infectious agent (immunization with altered agent or natural infection)
In passive immunity the individual…
Receives exogenous antibodies and does not confer to long-term immunity (mother-child via placenta or breast milk, and immunization with antibodies)
Herd immunity
Vaccinating part of the population to protect unvaccinated members of the population
What percent of population should be vaccinated to protect the “herd”
85%
Herd immunity does not protect against all vaccine-preventable diseases because…
Some diseases are caused by bacteria from the environment
People who depend on herd immunity:
-chemo patients
-people infected with HIV
-newborn babies
-elderly people
