Fiser Chapter 4 IMMUNOLOGY

Question 1

Types of T-cells

Answer 1

CD4 helper
CD8 suppressor
CD8 cytotoxic

Question 2

CD4 helper T-cells do what

Answer 2

IL-2 release -> maturation of CD8 cytotoxic T cells

IL-4 release -> B cell maturation into plasma cells -> Ab mediated humoral response

Delayed type hypersensitivity

Question 3

IL-2 leads to

Answer 3

maturation of CD8 cytotoxic T cells

IL-2 therapy (melanoma?):

• Converts lymphocytes to lymphokine-activated killer (LAK) cells by enhancing immune response to tumor
• Converts lymphocytes into tumor-infiltration lymphocytes

Question 4

IL-4 leads to

Answer 4

B-cell maturation into plasma cells -> Ab mediated humoral response

Question 5

CD8 suppressor cells do what

Answer 5

regulated CD4 and CD8 cells

Question 6

CD8 cytotoxic T cells do what

Answer 6

Recognize and attack non-self antigens attached to MHC class I receptors (e.g. viral gene products)

Question 7

Example of cell-mediated immunity

Answer 7

Intradermal TB skin test

Question 8

MHC class I (A, B, C) does what

Answer 8

All nucleated cells have it -> Presents Ag to CD8 cytotoxic cells -> CD8 cell activation

-Viral proteins

Question 9

MHC class II (DR, DP, DQ) does what

Answer 9

On all Ag-presenting cells (monocytes, dendritic cells) -> CD4 helper T-cell activation -> Interacts with B-cell surface IgM -> stimulates Ab formation

-Bacterial proteins

Question 10

Natural killer (NK) cells do what

Answer 10

Recognize cells that lack self-MHC -> natural immunosurveillance for cancer

• Not T or B cell
• Do not require MHC, prior exposure, or Ag presentation

Question 11

Antibody types

Answer 11

Ig GAMED

Question 12

IgG

Answer 12

• Secondary immune response
• Crosses placenta
• Opsonin, if x2 fixes complement

Question 13

IgA

Answer 13

• Secretions, Peyer’s patches, breast milk

- Prevents gut microbial adherence and invasion

Question 14

IgM

Answer 14

• Initial Ab after exposure to Ag
• Largest (5 domains, 10 binding site)
• Opsonin, x1 fixes complement

Question 15

IgE

Answer 15

• Allergic reactions

- Parasite infections

Question 16

Constant and variable regions of Ab

Answer 16

Constant: recognized by PMNs and macrophages. Fc fragment does NOT carry variable region

Variable: Ag recognition

Question 17

Polyclonal Ab

Answer 17

Multiple binding sites to Ag at multiple epitopes

Question 18

Monoclonal Ab

Answer 18

1 binding site to 1 epitope

Question 19

Hypersensitivity reactions

Answer 19

I: immediate, IgE and eosinophils

II: IgG or IgM reacts with cell-bound Ag

III: Immune complexes

IV: DTH

Question 20

Type I hypersensitivity

Answer 20

Eosinophils with IgE receptor for Ag -> binds Ag -> Major basic protein release -> mast cell and basophil activation -> histamine, serotonin, bradykinin release

-Bee stings, peanuts, hay fever

Question 21

Type II hypersensitivity

Answer 21

IgG or IgM reacts with cell-bound Ag

-ABO incompatibility (acute hemolysis), Grave’s disease, Myasthenia gravis

Question 22

Type III hypersensitivity

Answer 22

Immune complex deposition

-SLE, serum sickness

Question 23

Type IV hypersensitivity

Answer 23

Ag stimulates previously sensitized T cells

-TB skin test, contact dermatitis

Question 24

Histamine

Answer 24

Blood: from basophils
Tissue: from mast cells

Question 25

Primary and secondary lymphoid organs

Answer 25

Primary: liver, bone, thymus
Secondary: spleen, LNs

Question 26

Immunologic chimera

Answer 26

2 cell lines in one individual (BMT patients)

Question 27

Tetanus prone wounds

Answer 27

>6 hours old
Obvious contamination
Devitalized tissue
Crush
Burn 
Frostbite
Missile injuries

Question 28

Tetanus immunoglobulin

Answer 28

Give only with tetanus-prone wounds in patients not previously immunized or unknown

Question 29

Tetanus toxoid

Answer 29

-Always give tetanus toxoid unless sure patient had at least 3 doses and