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Flashcards in Inflammation and Immunity Deck (49)
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What are the major organs of the immune system?

Tonsils and adenoids, thymus, lymph nodes, lymphatic vessels, appendix, bone marrow, spleen, Peyer's patches


Name the innate and adaptive cells of humoral (antibody mediated) immunity.

Innate: Myeloid cells (non-host epitopes)
Adaptive: B cells (antibodies, also T helper cells, and APCs)


Name the innate and adaptive cells of cell mediated immunity.

Innate: NK cells (MHC existence)
Adaptive: T cells (MHC1-TCR)


What is the body's first line of defense?

The skin and mucous membranes.
They act as a physical barrier as well as an antimicrobial peptide barrier


Review the leukocytes involved in immune function and the inflammatory process.


{Platelets and erythrocytes
(all formed from myeloid stem cell)}


What types of leukocytes are the first to appear after injury?



What role do each of the leukocytes play in inflammation?

Neutrophils: first responders/begin phagocytosis
Macrophages- Ingest microbes and clean up debris after inflammatory response
Eosinophils- degranulate releasing cytotoxic chemical enzymes
Basophils/mast cells- degranulate releasing pro-inflammatory mediators


Describe the concept of a 'shift to the left of normal'

This shows more circulating immature cells known as band cells which indicates increased neutrophil production and acute infection.


Outline the 3 major types of lymphocytes.

NK cells
T Cells- Helper CD4 and Cytotoxic CD8
B cells


How do the lymphocytes specifically recognize foreign pathogen?

NK cells- innate immunity
Helper T cells(CD4)- via APC (B cells). Helper T cells recognize sequences on the MHC II and active an immune response triggering the release of lymphocytes to respond to a foreign pathogen.
Cytotoxic T cells(CD8)- Recognize the self sequences on the MHC I, if not recognized they active and eliminate.
B cells- Receptors allow B cells to recognize foreign epitopes (specific antigen) and bind/engulf to present to helper T cell. T cells recognize protein are then activated. Exposure to antigens prompts B cells to mature into antibody secreting plasma cells and memory cells.


What is the difference between MHC I and MHC II?

MHC I are surface proteins on the body's cells indicating the cells belongs there-'self'. (recognized by cytotoxic T cells and NK cells)

MHC II are surface proteins that bind with antigens and display them for helper T cells. in order to active the immune system (displayed by dendritic, macrophages and B cells and recognized by helper T cells)


Innate and specific/adaptive immunity are different because:

Innate immunity is nonspecific and caused by an immediate degranulation response, while adaptive immunity is mediated by specific B and T cells based on a prior exposure.


Antibodies have two regions:

Constant: determines the class of antibody
Variable: contains the sequence specific to the antigen/epitope


What does the complement system do?

The complement system enhances the body's response to foreign invaders: inflammation, chemotaxis, and lysis of target cells.


What are the different pathways of the complement system and how are they activated?

-Classical pathway- Activated by the C1 protein. Presence of an Ab is essential (IgG or IgM)=formation of antibody-antigen complex.
-Alternative pathway- Activated by C3 protein. Ab not need-can be activated on first exposure to antigen. Triggered by lipopolysaccharide in Gram neg bac walls and bac endotoxin.
-Lectin pathway- Activated by C2 and C4. Ab not need, can be activated on first exposure. Triggered by binding mannose on bacterial walls.


What are Kinins?

Small polypeptides that cause powerful vasodilation, increased vascular permeability and smooth muscle contraction when activated during inflammation. They are also responsible for pain.


How are the kinin and clotting systems linked?

Both the kinin and clotting system are activated by Factor XII (Hageman factor).


How is the complement system controlled?

Enzymes in plasma degrade activators and a number of inhibitory proteins are released. Ex- protein S prevents the complement membrane attack from attaching to and lysing cells.


Where are B and T cells produced and where do they mature?

B cells- Produced and mature in bone marrow
T cells- Produced in the bone marrow and mature in the thymus


What is clonal diversity?

All different types of T and B cells are randomly produced to have a receptor specific to one particular antigen. The specificity of an antigen is acquired upon formation of the cell.


What is clonal selection?

The theory that illustrates the selection of T and B cells that are specific to a particular antigen. This in turn causes proliferation/differentiation of that one particular T or B cell to create an army to fight off the recognized antigen


What is central tolerance?

Recognizing self antigens and not reacting to them. During the formation process in the generative organs lymphocytes are put through rigorous testing. Those that recognize self as a foreign antigen and have potential to attack self are eliminated via negative selection.


What is peripheral tolerance?

This same process of negative selection of self tolerance that happens in peripheral tissues.


What is SCID?

Severe combined immunodeficiency. Common lymphoid stem cell is absent=T, B, and in some case NK cells never develop. Most severe form is reticular dysgenesis. 'boy in the bubble.'


Describe Hypersensitivity Type I:

**IgE response to antigens (allergens)
-immediate reaction
-pl. B cells produce allergen specific IgE over repeated exposure IgE levels increased=increased response
**Mast Cells- activated by IgE antigen binding to IgE receptor site induces degranulation= histamine release, cytokines, arachidonic acid, protease, etc.


Describe Hypersensitivity Type II:

**IgG and IgM
**Tissue specific- antibodies that attack antigens on the surface of specific cells or tissues.
-Ex- bl. transfusion reactions, hemolytic disease of the newborn, IMMEDIATE significant graft rejection (host vs graft) all of these are examples of alloimmunity.


What is Alloimmunity?

A condition in which the immune system reacts against antigens of tissues from other members of the same species


Describe Hypersensitivity Type III:

**IgG and IgM (IgE)
**Failure of immune/phagocytic systems to effectively remove antigen-antibody complexes which are then deposited into tissues causing activation of the complement system and sustaining inflammation (immune mediated)
**Ab complexes carried in blood= can be distributed all over.
**Not immediate
-Ex- lupus (SLE)


Describe Hypersensitivity Type IV:

**T lymphocytes- cell mediated, no primary antibody
**Antigen stimulates T cells to differentiate into cytotoxic T cells and helper T cells
**Delayed onset
-Ex- delayed rejection (graft vs. host), contact dermatitis


What is a primary immune disorder?

Congenital phenotypes that result from abnormal development or maturation of immune cells (ex SCID) and primary disorders of immune cells (ex HIV/AIDS)