Immunology

Question 1

what properties does ammonia have

Answer 1

anti bacterial

Question 2

what cells are found in the epidermis

Answer 2

• keratinocytes
• langerhans cells
• CD8+ T cells
• melanocytes etc

Question 3

what cells are found in the dermis

Answer 3

• CD8 and 4 T cells
• macrophages
• NK cells
• fibroblasts
• lymph, vasculature etc

Question 4

what do keratinocytes produce

Answer 4

• cytokines in response to injury/skin disease
• AMPs

Question 5

what do AMPs do

Answer 5

can directly kill pathogens

Question 6

AMPs in people with psoriasis

Answer 6

found in high amounts

Question 7

what can keratinocytes be activated by

Answer 7

• damage
• UV light
• sensitizers

Question 8

langerhans cells

Answer 8

• dendritic (APC) cells that are found in the epidermis
• characterised by the Birbeck granule
• migrate throughn epidermis and dermis and travel via lymphatics to present antigen in lymph nodes

Question 9

where are Langerhans cells formed

Answer 9

bone marrow

Question 10

what T cells are found in the epidermis

Answer 10

CD8+ T cells

Question 11

which T cells are found in the dermis

Answer 11

CD4 and 8 + T cells

Question 12

which T cells are associated with psoriasis

Answer 12

CD4 + Th1 and 17

Question 13

which T cells are associated with atopic dermatitis

Answer 13

CD4 + Th2 and 17

Question 14

where are T cells produced

Answer 14

produced in bone marrow and mature in thymus

Question 15

CD4+ T helper cells

(Th1 and 2 and their effector cytokines)

Answer 15

• T_H1 activate macrophages to destroy micro-organisms. Their effector cytokines are IL2 and IFNg
• T_H2 activate B cells to produce plasma cells which produce antibodies. Their effector cytokines are IL-4, -5 and -6

Question 16

CD8+ T cells

Answer 16

can kill infected cells directly

Question 17

name 3 types of dendritic cell found in the dermis

Answer 17

• dermal DC
• plasmacytoid DC
• APC

Question 18

dermal DC

Answer 18

involved in Ag presenting and secreting cytokines and chemokines

Question 19

plasmacytoid DC

Answer 19

produce IFN alpha and are found in diseased skin

Question 20

which DC is found in diseased skin in the dermis

Answer 20

plasmacytoid DC

Question 21

which chromosome do MHC occur on

Answer 21

6

Question 22

MHC class II

Answer 22

• found on APC - macrophages, B cells, dendritic cells
• an APC takes up an antigen, processes it and retains a fraction called an epitope on the APC surface
• this is presented to helper T cells (CD4 receptors) with the MHC class II

Question 23

MHC class I

Answer 23

• these are found on almost all cells
• present the epitope of atngien to cytotoxic T cells, which express CD8 receptors
• this triggers the cell to undergo apoptosis and die

Question 24

immunology in psoriasis

Answer 24

• under stress release factors that stimulate the pDC to produce IFN alpha and release IL-1 beta, IL6 and TNF
• TH1 and 17 are activated and are attracted to the dermis
• dermal fibroblasts beome involved

Question 25

mutation in which gene is associated with early onset/severe asthma

Answer 25

filaggrin gene

Question 26

what is AMP like in atopic dermatitis

Answer 26

decreased, this may account for increased susceptibility to infectin

Question 27

what happens to the skin barrier in atopic dermatitis

Answer 27

it is impaired: key factor * allows access/sensitisation to allergen and promotes colonisation by microorganism * immunlogical cells attracted by stressed KC