Lecture 2: Intro to Immunology Flashcards
What is the most common manifestation of an infection?
Fever.
It inhibits the proliferation of an infection
What are extracellular and intracellular microbes?
Extracellular microbes can survive in animals by growing extracellularly, as long as they have nutrients.
Intracellular microbes invade, live and replicate intracellularly and use the hosts energy sources.
Characteristic of all microbes
They can
- Grow
- Reproduce
- Infect humans
What are self-particles?
Those that are made by your body. Something that is self should NOT be targeted or destroyed by the immune system.
What are non-self particles?
Sometimes called foreign bodies.
Particles NOT made by your body that can be recognized as potentially harmful by making antigens.
What are antigens?
Antigens are made by non-self particles and let the body know that they want to damage.
What is a cytokine?
Molecules that are used in cell-signaling to communicate with neighboring cells about initiating a immune response.
They also trigger movement to a specific part of the body.
What are chemokines?
Chemokines are release by an infected cell and initiate an immune response by warning neighboring cells.
Immunity is a set of _________________, which can protect us against diseases.
cooperative defense mechanisms
Immune responses against microbes (pathogens) can cause what?
Damage to tissue: aka; collateral damage.
_______ can elicit an autoimmune response.
Self-antigens.
If self-antigens are attacked; autoimmune response.
The immune system is made up of what 2 elements?
- Fixed elements, which are lymphoid organs that can be primary or secondary.
- Mobile elements, which are immune cells or soluble (humoral) components, such as antibodies, complement and acute phase proteins.
Primary fixed elements
- Bone marrow
2. Thymus
Secondary fixed elements
- Spleen and lymph nodes
2. Mucosal immune tissues
Roles of immune system
- Defend against infections and tumors
- Can injure cells and cause inflammation
- Recognize and responds to tissue grafts and new proteins, which is often a barrier to transplants.
What is the most effective method of protection against infections?
Vaccinations, which stimulate a immune response against pathogens.
What is herd immunity?
As more people are vaccinated, the spread of disease decreases
What is the difference between active and specific immunity?
Active immunity is the immunity to a dz acquired by making your own antibodies when you are exposed to the dz through infection or vaccination.
Passive immunity occurs when you are given antibodies or t-lymphocytes to a disease rather than making them yourself.
Both help to resist infection and are specific. However, only active immunity generates memory.
What are the 2 types of immunity?
- Innate immunity
2. Adaptive (acquired) immunity
What is innate immunity?
Innate immunity is our first line of defense that as soon as something attacks.
It has SOME specificity for antigens but has no memory.
It creates acute inflammation.
What is adaptive immunity?
Adaptive immunity develops more slowly and occurs only after the body has experienced an initial attack. Thus, it has memory for SPECIFIC antigens.
Compare and contrast the diversity of innate immunity and adaptive immunity
Innate immunity does not have much diversity; it provides generalized protextion
Adaptive immunity, on the other hand, is very diverse. Different receptors are made by somatic recombination.
Which react to self:
Innate immunity or adaptive immunity?
Neither.
Innate immune system first line of defense and second line of defense
Induced?
Specific?
1st line of defense is NON-induced and NON-specific: skin, saliva, pH of stomach.
2nd line of defense is INDUCED and BROADLY-SPECIFIC. Inflammatory response try to fight off infection: phagocytosis, compliment activation and secretion of cytokines. It occurs 4-96 hours after infection
What is phase 3 of defense?
Adaptive immunity- a HIGHLY SPECIFIC response to an antigen initiated by
- B cells (Ab)
- helper T-cells
- Cytolytic t-cells
Examples of cells of innate immunity
- Skin
- Mast cells
- Phagocytes
- Dendritic cells
- Compliment
- NK and ILCs
How do our cells of innate immunity act so quickly?
They circulate in our blood and delivered to tissue on demand.
Which immune cells live in our blood?
- Neutrophil
- Eosinophil
- Basophil
- Monocyte
- T-cell
- B- cell
- NK cell
- Platelets
- RBC
Which immune cells are located in our tissues?
- Tissue eosinophil
- Mast cells
- Macrophages
- T-lymphocyte
- Plasma cell
- NK cell
Phagocytes?
- Neutrophil
- Monocytes
- Macrophages
What are the 4 polymorph granulocytes of innate immunity?
- Basophil
- Eosinophil
- Basophil
- Mast cells
Granules are released on-demand of infection
Infection and tissue damage can lead to what?
- Heat
- Redness
- Swelling
- Pain
- Loss of function
What do innate immune cells originate from?
Pluripotent HCS, which the differentiate to become CMD (common myeloid progenitors)
Our innate immune cells will be derived from the common myeloid progenitors + NK cells.
What is CD?
Stands for [cluster of differentiation], which allows cells to be identified by the receptor on their surface.
What are the 4 mononuclear cells of innate immunity?
- Monocyte
- Macrophage
- Dendritic cells
- NK cells
NK cells are raised as ____________, but assist in _______________.
Lymphocyte
Innate immunity
Primary fx of phagocytes?
Phagocytes are long living because they require little maintenance.
Ingest, destroy pathogens and get rid of damaged tissues (scavenger cells)
Steps in the response of phagocytes?
RRID
- Recruitment to the site of infection
- Recognize pathogen and get activated
- Ingest via phagocytosis
- Destruct
Once activated, they secrete cytokines
Do cytokines act on every cell?
No. that cell must have a [R] for it.
Neutrophils are also called what?
What is something crazy about neutrophils?
Neutrophils are called polymorphonuclear leukocytes because their nucleus has 3-5 lobes.
Most abundant population of circulating spherical WBC, which help in the earliest phase of inflammatory reactions.
What is the most abundant population of circulating WBCs?
Neutrophils
Where are neutrophils made and what do they arise from?
Bone marrow and arise from precursors that ALSO make mononuclear phagocytes.
Production of neutrophils is stimulated by cytokine called what?
granulocyte colony‐stimulating factor (G‐CSF)
Life of a neutrophile
we make 10^11 in a day and each circulated in blood for hours or a few days.
After they enter tissues, they only fx for 1-2 days then DIE.
Mast cells, basophils and eosinophils
- All involved in innate and adaptive immunity
- Protect against helminthes and allergic reactions
- All have cytoplasmic granules