Skin Immunology

Question 1

Factors that contribute to skin as an immunological system?

Answer 1

Structure
Cell types
Cytokines, chemokines, eicosanoids, antimicrobial peptides
Genetics

Question 2

What is hypersensitivity?

Answer 2

Overreaction to an antigen

Question 3

What is immunodeficiency?

Answer 3

Infection not controlled

Tumours may form

Question 4

What is the keratin layer?

Answer 4

Tough
Lipid rich
Physical Barrier

Question 5

How is keratin layer formed?

Answer 5

Terminal differentiation of keratinocytes to corneocytes

Question 6

Important structural proteins in keratin layer?

Answer 6

Filaggrin

Keratin

Question 7

What is the keratin layer also known as?

Answer 7

Stratum corneum

Question 8

What are Langerhan cells?

Answer 8

Type of dendritic cells that intersperse with keratinocytes in the epidermis
(Look like tennis rackets)

Question 9

What type of T cells are mainly found in the epidermis?

Answer 9

CD8+ T cells

Question 10

What layer are CD4+ and CD8+ T cells are found in?

Answer 10

The dermis

Question 11

What process are CD4+ TH cells associated with?

Answer 11

Inflammation

Question 12

What is TH1 associated with?

Answer 12

Psoriasis

Question 13

What is TH2 associated with?

Answer 13

Atopic dermatitis

Question 14

What is TH17 associated with?

Answer 14

Psoriasis

Atopic dermatitis

Question 15

What does CD stand for?

Answer 15

Cluster of designation

eg CD8+

Question 16

Where are T cells produced?

Answer 16

Bone marrow

Question 17

Where are T cells sensitized?

Answer 17

Thymus

Question 18

Expressed by means?

Answer 18

Made by, found in

Question 19

What is the basis of cell-mediated immunity?

Answer 19

T cells

Question 20

What are CD4+ cells?

Answer 20

Helper cells

Question 21

Types of CD4+ cells?

Answer 21

TH1 - activate macrophages to destroy microorganisms
IL2, IFNy
TH2: Help B cells to make Ab
IL4. IL5, IL6`

Question 22

What are CD8+ cells?

Answer 22

Cytoxic T cells

Question 23

What do CD8+ cells do?

Answer 23

Can kill infected cells directly

Important protection against viruses and cancer

Question 24

Different types of dendritic cells?

Answer 24

Dermal DC

Plasmacytoid

Question 25

What are dermal dendritic cells involved in?

Answer 25

Ag presenting and secreting cyto/chemokines

Question 26

Where are plasmacytoid DCs found and what do they produce?

Answer 26

IFNa | Diseased skin

Question 27

Other cell types in dermis?

Answer 27

Slide 12

Question 28

Other cell types in dermis?

Answer 28

Slide 12

Question 29

Skin condition associated with inappropriate immune response/inflammation?

Answer 29

``` Psoriasis Atopic dermatitis Bullous pemphigoid Contact dermatitis Morphea/systemic sclerosis Urticaria Systemic lupus erythematous Skin infections Skin tumours ```

Question 30

MHC class 1 found where?

Answer 30

Found on almost all cells

Question 31

What do MHC class 1 present?

Answer 31

Ag to cytoxic T cells | Endogenous Ag

Question 32

MHC class2 found on?

Answer 32

APC (B cells, macrophages)

Question 33

What do MHC2 present to?

Answer 33

TH cells

Question 34

Plaques are irrevrrsible in Psoriasis? True or false?

Answer 34

False | Reversible

Question 35

Hallmark of psoriasis skin lesions?

Answer 35

Inflammation

Question 36

What happens when a Keratinocyte is under stress?

Answer 36

Release factors that stimulate pDC to produce IFNa | Release IL-1B/IL-6 and TNF

Question 37

Chemical signals activate Dendritic cells and then they?

Answer 37

Migrate to skin draining lymph node to present to and activate T cells (TH1 & TH17)

Question 38

Atopic eczema is commonest in?

Answer 38

Children

Question 39

How do psoriasis and atopic eczema differ?

Answer 39

Histologically

Question 40

What happens when T helper cells differentiate?

Answer 40

They either make IFNg, IL2, IL4, IL5, IL13,

Question 41

Atopic mean?

Answer 41

Allergic

Question 42

TH1 actiavtes?

Answer 42

Virus defence

Question 43

TH2 activates?

Answer 43

B cells

Question 44

Treating bad atopic eczema?

Answer 44

Antibody against IL4/IL13 | Called dupilumab

Question 45

50% of patients with atopic eczema have?

Answer 45

Filigrin mutation

Question 46

Icthyosis Vulgaris?

Answer 46

Filagrin is broken but no eczema just very dry skin

Question 47

Autoimmunity factors?

Answer 47

``` Lymphocyte abnormalities Intercell communication Genetic predisposition Anatomic alterations Hormonal influence Infection ```

Question 48

Type 1 immediate hypersensitivity is?

Answer 48

Allergy | IgE mediated

Question 49

Type 2 hypersensitivity is ------ mediated?

Answer 49

Antibody