skin immunology Flashcards
what function does the keratin layer/ epidermis have in skin defence and what proteins
physical lipid barrier, proteins: filaggrin, involucrin, keratin
what function does the keratinocytes have in skin defence, where are they, how do they initiate immune response
in epidermis activated by UV or pathogens and produce AMP’s, cytokines and chemokines
what function does the langerhans have in skin defence, where are they, how do they initiate immune response
prickle cell layer, they are main immune cells and are dendritic APC’s that produce Ag and present to effector T cells
what do langerhans have that make them identifiable
birbeck granules
what T cells are mainly in epidermis vs dermis
epidermis = CD8, dermis = CD4 and CD8 (NK’s also in both)
what CD4 T cell is associated with psoriasis
TH1
what CD4 T cell is associated with atopic dermatitis
TH2
what CD4 T cell is associated with psoriasis and atopic dermatitis
TH17
what do Th1 cells do and what are they activated by
activated by IL2, cause cellular disease (autoimunne) –> produces mainly macrophages
what do TH2 cells do and what are they activated by
activated by IL4, humeral response (allergies) –> activate B cells
what action does CD4+ have
once activated can become either Th1 or Th2 (activates B cells)
what action does CD8+ have
cytotoxic, direct cell killing
what immune cells are present in epidermis
Langerhans and T cells
what immune cells are present in dermis
dendritic (dermal and plasmacytoid), macrophages, NCK’s, T cells
where is MHC I present and what does it present to
on all cells CD8+T
where is MHC II present and what does it present to
on APC cells to CD4+T
what are the first immune steps in psoriasis
stressed keratinocytes produce IFNa and TNF, T cells attracted and secrete IL 17
after IL17 in psoriasis is released what happens to keratinocytes
proliferation, AMP release, attract neutrophils, dermal fibroblasts release growth factor
what is an example of a derm type I allergic reactions
anaphylaxis, food allergies, hay-fever, eczema
what is an example of a derm type II allergic reactions
blood transfusion reactions
what is an example of a derm type III allergic reactions
Arthurs, SLE, RA
what is an example of a derm type IV allergic reactions
allergic contact dermatitis
what are the symptoms of a type 1 reaction
urticaria (itchy hives, oedema in dermis, appear quickly), angioedema (non-pitting), wheezing, anaphylaxis
what is the test for type 1 hypersensitivity
skin prik test, challange test, serum mast cell
what is the test for type IV hypersensitivity
patch test
what is the management for type 1 hypersensitivity
1) antihistamines 2) prednisilone 3) adrenaline
