Defense II

Question 1

natural innate immunity

Answer 1

1) omnipresent and never changing

Question 1

antibody

Answer 1

1) IgM
- first antibody released into circulation
2) IgG
- major antibody of immune response
3) IgE
- found on the surface of the mast cells
- mediates hypersensitivity reaction
4) IgA
- milk, saliva, and tears
5) IgD: bound on B cells and rarely released into circulation

Question 2

acquired adaptive immnity

Answer 2

1) adapts over time
2) humoral and cellular

Question 3

T lymphocytes

Answer 3

1) characterized by expression of specific surface markers
- CD3 on all T cells (transduction of signals after antigen has been bound)
- CD4 helper T cells (cytokines)
- CD8 cytotoxic T cells (cell-mediated immunity)
2) mediators of innate immunity
- 60-70% of circulating lymphocytes
- recognize cell-bound antigen by means of antigen-specific TCR

Question 4

TCR

Answer 4

1) heteroreceptor
2) antigen is bound
3) contains Cd3

Question 5

B lymphocytes are

Answer 5

1) 10-20% of circulating lymphocytes
2) mediators of humoral immunity and secrete Igs
3) IgM is on all B cells for antigen receptor
4) CD20 and CD21 are expressed on B cells

Question 6

natural killer cells

Answer 6

1) 10-15% of circulating lymphocytes
2) abundant granules to lyse tumor cells and virally infected cells without previous sensitization
3) CD16 represents Tc receptor for IgG and allows NK to lyse them!!
4) antibody dependent cell mediated cytotoxicity
5 )do not kill normal cells because they have self class I molecules

Question 7

macrophages

Answer 7

1) mononuclear phagocytic system
2) required to process and present antigen to T cells
- class II MHC
3) produce cytokines that influence B and T cells
4) lyse tumor cells and secrete toxic metabolites

Question 8

dendritic cells

Answer 8

1) located in lymphoid tissue

Question 9

langerhans cells

Answer 9

1) in the epidermis
2) both have large amounts of class II molecules on their surface
3) present antigens to T cells

Question 10

cytokines

Answer 10

1) protect against viral infections
- non specific inflammatory response
2) regulate lymphocyte growth
3) activate other inflammatory cells
4) chemotaxis of WBC
5) stimulate hematopoiesis with CSF

Question 11

major histocompatibility complex

Answer 11

1) class I
- on all nucleated cells and platelet
- involved with action of cytotoxic T-lymphocytes CD8+
2) class II (HLA-D)
- antigen resenting cells (macrophages and dendritic cells
- involved in the pathway to specific immune response
- CD4+

Question 12

remember 8

Answer 12

1) MHC 1 to CD8+
2) MHC 2 to CH4+

Question 13

immune mechanisms and tissue damage

Answer 13

1) all can cause damage
2) hypersensitivity reaction
- usual or normal response to antigen can cause it

Question 14

type I anaphylactic shock is

Answer 14

1) reaction within minutes after exposure to antigen (immediate hypersensitivity)
2) localized or systemic
3) vasoactive amines and things from mast cells
4) IgE
5) allergen => B cells make IgE => igE binds mast cells and basophils => reexposure causes binding again and initiation of reaction with POWERFUL mediators

Question 15

systemic anaphylaxis

Answer 15

1) begins with itching and hives followed by respiratory difficulty (constriction of bronchioles)
- can have upper airway obstruction
- can be fatal within minutes

Question 16

local reactions

Answer 16

1) atopic = hereditary
2) occur on skin or mucosa
3) fever, bronchial asthma, gastroenteritis
4) several parasitic infections => IgE

Question 17

type II antibody mediated type

Answer 17

1) complement mediated
- Abs react with cell surface Ag
- complement causes cell lysis
- RBC commonly damaged
2) IgG or IgM against normal cell tissue
- Ags are intrinsic to the cell or tissue damaged
–
1) antibody dependent cell mediated cytotoxicity
- cell types that bear Fc portion of IgG cause lysis of target cells coated with it
- not phagocytosis or complement
2) antibody mediated cellular dysfunction
- Abs directed against cell surface receptors
- noncytotoxic but impair function
- grave’s disease

Question 18

target cells

Answer 18

1) Ab will attach to NK => lysis
or
2) Ab recognize acetylcholine receptor and doesn’t allow the impulse to happen

Question 19

type III immune complement mediated

Answer 19

1)Ag- Ab produce tissue damage by activation of serum mediators
2) activation of complement and accumulation of PMNs
3) effect on kidneys
- lupus

Question 20

systemic immune complex disease (type iii)

Answer 20

1) formation of immune complexes against endogenous or exogenous Ags
- deposit of complexes in tissue
- neutrophil recruitment
2) acute and self-limiting
- fever, arthralgia, and acute necrotizing vasculitis and ischemic necrosis
- kidneys, joints
3) chronic disease develops with persistent or repeated exposure to Ag
- SLE and rheumatoid arthritis

Question 21

local immune complex disease (type iii)

Answer 21

1) arthus reaction
2) local tissue necrosis from immune complex vasculitis
3) similar to systemic form
- necrotizing vasculitis and neutrophil accumulation

Question 22

type IV cell mediated hyper sensitivity reaction

Answer 22

1) delayed hypersensitivity
2) CD4 t cells exposure to Ags bound to self MHC molecules
3) attracts macrophages and induced inflammation
-POISON IVY
- granulomas
4) T-cell mediated cytotoxicity
5) perivascular cuffing of monocytes and lymphocytes which leads to vascular permeability with edema and fibrin
6) caused by persistent and non-degradable Ags

Question 23

type IV cell mediated cytotoxicity

Answer 23

1) Mediated by CD8 cells which kills Ag bearing target cells
2) Clas 1 MHC bind to and present Ag to t hese cells
- graft rejection
3s)CTL secrete molecules which drill holes in target cells causing apoptosis

Question 24

summary

Answer 24

1) type I
- allergies
- asthma
2) type II
- autoimmune to antibody
3) Type III
- hypersensitivity: immune complex
4) type IV
- t cells

Question 25

transplantation of hematopoietic stem cells

Answer 25

1) graft - versus host disease
- donor cells recognize host as foreign
- necrosis of epithelial cells of skin, gut, and liver
2) transplantation rejection
- mediated by radiation resistant T cells and NK
- absence of normal self class I molecules

Question 26

autoimmune diseases

Answer 26

1) immune reaction to self antigens
2) single organ cell type disorders
- IDDM, graves
3) multisystem disease
- SLE, rheumatoid arthritis, sjogrens disease

Question 27

mechanism of autoimmune disease

Answer 27

1) loss of self-tolerance
2) genetic factors
3) microbial agents