Immune System Flashcards
Basophils, eosinophils, neutrophils, mast cells and natural killer cells are part of _______ immunity.
Innate
Macrophages and dendritic cells, also part of innate immunity, act as ________ _______ cells and help trigger ________ immunity.
antigen presenting; adaptive (there is overlap and B cells can also be APCs).
These two types of cells and their variants are part of adaptive immunity.
B & T cells
How are B cells activated to make antibodies?
encounter antigen, engulf it, present to helper T cell, which activates B cell (becomes plasma cell and produces antibodies).
How are T cells activated?
Antigen presenting cells only
Name the 4 cardinal signs of inflammation and their causes.
Redness- increased blood flow (hyperemia)
Heat- from increased blood flow
Swelling- increased flow causes exudate to move to are of infection
Pain- increased flow can compress nearby nerves
Differentiate between an abscess and granuloma
Abcess- wall of collagen fibers around pus
Granuloma- infected macrophages that can’t destroy invader get surrounded by uninfected macrophages
Name the 4 steps of phagocyte mobilization.
- Leukocytosis (neutrophils enter blood from bone marrow)
- Margination (neutrophils cling to blood vessel walls via CAMs)
- Diapedesis (neutrophils flatten and squeeze out of leaky blood vessel)
- Chemotaxis (neutrophils follow chemical trail of inflammatory chems to site of infection)
This protein is produced when a virus infects a cell and begins self replicating. The dying cell releases the protein to surrounding cells, which bind the protein via surface receptors. This binding tells these cells to produce antiviral proteins.
Interferon
C3a enhances the inflammation response. C3b is a/an ________, which coats the surface of pathogens leading to enhanced phagocytosis.
Opsonin
________ is a ring of complement proteins that insert into the plasma membrane of the target cell, create a pore which leads to cell lysis via osmosis.
Membrane attack complex (MAC attack!!)
What is an opsonin? Name two opsonins besides C3b
Substance that binds the surface of a cell leading to enhanced phagocytosis. Antibodies or lectin.
Released by leukocytes and macrophages, ______ act at the hypothalamus to increase body temp.
pyrogens
How is a moderate fever beneficial?
Causes liver and spleen to sequester iron & zinc, and increases metabolic rate which increases the rate of repair.
This type of immunity is specific, systemic, and uses memory.
Adaptive
Name three main differences between humoral and cellular immunity.
Humoral- B cells, control extracellular pathogens, bind specific antigen, make antibodies
Cellular- T-cells, control intracellular pathogens, activated by exposure to antigen on APC
_______ has antigenic determinants while the variable site on ______ binds the antigenic determinant.
Antigens, antibodies
These self markers on body cells label them as friends and should be tolerated by the immune system.
Major histocompatibility complex (MHC) proteins
_______ are present on all nucleated cells while _______ are present on APCs.
MHC Class 1, MHC Class 2
What is lymphocyte seeding?
when lymphocytes move into secondary lymphoid organs and circulation
_______ is when a lymphocyte recognizes self MHCs
immunocompetence (from positive selection- failure results in apoptosis)
_______ is when a lymphocyte is unresponsive to self antigens.
self-tolerance (from negative selection- eliminates self-reactive T-cells)
Name the 3 APCs
Dendritic cells, macrophages, and B cells
________ help further activate/mature/multiply B cells
Helper T cells
These differentiated B cells produce antibodies.
Plasma cells
Antibodies (or immunoglobulins) have a constant region that determines it’s class and a ______ region that forms the antigen binding site.
variable
This antibody is released during the early immune response and can activate complement.
IgM
This antibody is bound to mast cells or basophils and is involved with inflammation and allergies.
IgE
This is the most abundant type of antibody and is the main one in the secondary immune response.
IgG
This antibody is an important B cell receptor
IgD
This antibody is found in epithelial areas like the mucus, saliva, and breast milk.
IgA
_______ is when antibodies bind the dangerous parts of a bacteria/virus.
Neutralization
For antigens in solution, antibodies bind these antigens and form a clump in a process called _______.
Precipitation
When mothers pass antibodies to their fetus, this is naturally acquired _______ immunity.
Passive
When you receive preformed antibodies via injection, this is considered artificially acquired ______ immunity
Passive
What are CD4 and CD8?
coreceptors alongside T-cell receptors
T-cells with CD4 receptors bind cells with MHC 1 or MHC2?
MHC2
T-cells with CD8 bind cells with MHC 1 or MHC2?
MHC1
What is the function of cytotoxic T cells, which coreceptor does it have, and which MHC does it bind?
Destroy virus-infected or cancerous “self” cells, CD8, MHC2
Summarize MHC restrictions.
Since naive CD8 cells must be activated by an APC, and only recognize MHC1, they are only able to be activated by dendritic cells, which have both MHC1 and MHC2. They can’t be activated by other nucleated cells with MHC1. Must be an APC.
_______ ________ is when the T-cell receptor and CD4/8 recognizes the antigen-MHC complex. This is required for T-cell activation.
Double recognition
Co-__________ is when the receptor on the T-cell binds the costimulatory molecule on the APC.
stimulation
These help further stimulate B-cell proliferation and T-cell enlargement and proliferation.
Cytokines
CD4 T-cells differentiate into _______ and ________.
Helper T-cells and memory T-cells.
What happens to T-cells 7-30 days after immune response and why?
Apoptosis; T-cells produce inflammatory cytokines and must be disposed of when no longer needed.
Helper T-cells are involved in humoral immunity by bind the B-cell MHC2-antigen complex with its TCR and CD4 protein, the release ________ as a costimulatory signal to complete B-cell activation.
interleukins
How is the helper T-cell important in cellular immunity?
It binds dendritic cells and stimulates it to express costimulatory molecules which allows the dendritic cell to activate the CD8 cell with interleukin 2.
Regulatory T-cells enhance/dampen the immune response by secreting cytokines.
dampen
Cytotoxic T-cells, when activated, recognize the antigen on the MHC1 and binds tightly, degranulating which releases ________ and ________, which insert into the target cell plasma membrane forming a pore, and enter the target cell and activate enzymes that trigger apoptosis, respectively.
perforin, granzymes
Allograft - 2 individuals of the same species
Xenograft- 2 individuals of different species
Isograft- 2 genetically identical individuals
_______- self graft
Autograft
Immunosupressive therapy can be dangerous because they kill rapidly dividing lymphocytes, which can lead to ________
bacterial/viral infection
