A 10 Acute Cutaneous Inflammation

Question 1

What does SALT stand for, and what is it associated with?

Answer 1

• skin associated lymphoid tissue.

- Cutaneous adaptive immune response.

Question 2

What are the known PAMP’s?

Answer 2

• Bacterial lipopolysaccharide
• Peptidoglycan
• Lipoteichoic acids
• Mannans & Glucans
• Bacterial DNA

Question 3

Langerhans has what unique organelle?

Answer 3

Birbeck granule

Question 4

Helper T cells have what function & what receptor?

Answer 4

-Get other immune cells involved
-CD4
(think “4 Helps, but double is death!” 8)

Question 5

Cytotoxic T cells have what function & receptor?

Answer 5

• Kill marked cells

- CD8

Question 6

What cell presents antigens to T cells waiting in lymph nodes?

Answer 6

Langerhans

Question 7

What tells T cells to go to the skin?

Answer 7

T-cells bound to CLA (cutaneous lymphocyte antigen)

Question 8

Helper T Cell Subset Th1: what function?

Answer 8

Intracellular pathogens (like viruses)

Question 9

Helper T cell subset Th2: what function?

Answer 9

Helminth infections

Question 10

Helper T cell subset Th17: what function?

Answer 10

Autoimmune

Question 11

Helper T cell subset Treg: what function?

Answer 11

Immune suppression

Question 12

Immediate Hypersensitivity reactions involve which immune cells?

Answer 12

-Mast cells (rls histamine)

-

Question 13

Which cells can be involved in antigen presenting?

Answer 13

• Macrophages
• Dendritic cells
• B cells
• Keratinocytes (though not as efficiently)

Question 14

How long until Triple Response of Lewis occurs?

Answer 14

3-10 seconds

Question 15

What are 3 phases of Triple Response of Lewis?

Answer 15

• Erythema=Capillary dilation
• Flare=Nearby arterioles
• Wheals=Up vascular permeability

Question 16

All gram-negative bacteria have what PAMP?

Answer 16

Lipopolysaccharides

Question 17

What 3 groups of molecules (not cells) serve as the “bridge” from innate immune response to adaptive immune response in the skin?

Answer 17

• co-stimulators, cytokines, chemokines: recruit & activate lymphocytes
• MHC Class II: presented along w/ the antigen to T-cells
• Co-stimulatory molecule: CD-80 & CD-86

Question 18

Which type of T cell has the CLA antigen bound to it?

Answer 18

Memory T cells

Question 19

What is the primary purpose of CLA-positive T cells?

Answer 19

Cutaneous Immunosurveillance

Question 20

What is the mechanism of Type I (Immediate) Cutaneous Hypersensitivity reaction?

Answer 20

IgE’s bound to mast cells become cross-linked, causing mast cell degranulation -> inflammation or anaphylaxis

Question 21

What is the mechanism of Type 2 Cutaneous Hypersensitivity Reactions?

Answer 21

-“Antibody-dependent.”Antibodies attach to antigens which have (mistakenly) collected on skin cells. Killer T cells and complement activation produce cytotoxicity. (Ex, hemolytic anemia, transfusion rxn, some autoimmune disorders, POSSIBLY vitiligo)

Question 22

What is the mechanism of Type 3 Cutaneous Hypersensitivity reactions?

Answer 22

“Immune Complex Disorders.” Antibodies and antigens form Immune Complexes in the blood. Deposit in vessel walls, esp. small vessels in skin. Complement Activation, platelet aggregation, and Lysosomal Enzyme Release causes vascular damage. (ex, lupus erythematosis & dermatomyositis)

Question 23

What is the mechanism of Type 4 Cutaneous Hypersensitivity Rxn?

Answer 23

• Antigen presented to T-cell by antigen-presenting cell.
• Cytokines rls’d, amplifying T-cell and macrophage recruitment (seen in allergic contact dermatitis, tuberculosis, leprosy)

Question 24

What are 3 skin immune system cells/chemicals that are suppressed by UV light?

Answer 24

• Langerhans
• Thy1+
• Dendritic epidermal T cells