Immunology Flashcards
what properties does ammonia have
anti bacterial
what cells are found in the epidermis
- keratinocytes
- langerhans cells
- CD8+ T cells
- melanocytes etc
what cells are found in the dermis
- CD8 and 4 T cells
- macrophages
- NK cells
- fibroblasts
- lymph, vasculature etc
what do keratinocytes produce
- cytokines in response to injury/skin disease
- AMPs
what do AMPs do
can directly kill pathogens
AMPs in people with psoriasis
found in high amounts
what can keratinocytes be activated by
- damage
- UV light
- sensitizers
langerhans cells
- 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
where are Langerhans cells formed
bone marrow
what T cells are found in the epidermis
CD8+ T cells
which T cells are found in the dermis
CD4 and 8 + T cells
which T cells are associated with psoriasis
CD4 + Th1 and 17
which T cells are associated with atopic dermatitis
CD4 + Th2 and 17
where are T cells produced
produced in bone marrow and mature in thymus
CD4+ T helper cells
(Th1 and 2 and their effector cytokines)
- TH1 activate macrophages to destroy micro-organisms. Their effector cytokines are IL2 and IFNg
- TH2 activate B cells to produce plasma cells which produce antibodies. Their effector cytokines are IL-4, -5 and -6
CD8+ T cells
can kill infected cells directly
name 3 types of dendritic cell found in the dermis
- dermal DC
- plasmacytoid DC
- APC
dermal DC
involved in Ag presenting and secreting cytokines and chemokines
plasmacytoid DC
produce IFN alpha and are found in diseased skin
which DC is found in diseased skin in the dermis
plasmacytoid DC
which chromosome do MHC occur on
6
MHC class II
- 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
MHC class I
- 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
immunology in psoriasis
- 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
mutation in which gene is associated with early onset/severe asthma
filaggrin gene
what is AMP like in atopic dermatitis
decreased, this may account for increased susceptibility to infectin
what happens to the skin barrier in atopic dermatitis
it is impaired: key factor
- allows access/sensitisation to allergen and promotes colonisation by microorganism
- immunlogical cells attracted by stressed KC
