Immunology Flashcards
What factors contribute to the skin as an immune system
Structure - keratin layer and stratification
Cells - immune cells and keratinocytes
Cytokines, chemokines etc
Genetics
What is autoimmunity
When there is a reaction to host tissue
Leads to chronic inflammation
What can activate keratinocytes
UV light
Sensitisers - such as in allergic contact dermatitis
How do Langerhans cells trigger the immune response
The process antigens and migrate away from the epidermis to the lymph system to present them to T cells
What do Birbeck granules look like
Tennis rackets
What T cells are found in the epidermis
CD8+
What T cells are found in the dermis
CD4+ and CD8+
Where are T cells produces
Bone marrow
How does T cell activation and antigen recognition occur
Through interaction with the T cell receptor (TCR) and the Major Histocompatibility Complex (MHC)
Describe the function of Mast cells
Effectors of the IgE mediated response - allergy
IgE binding causes activation of mast cells and release of inflammatory mediators
The degranulate and release many mediators such as histamine, interleukins and TNF
What are MHC proteins
An identity tag protein that sticks out of every cell and allows the body to identify it as self
Can also show which proteins are present in the cell
If a cell lacks MHC it is attacked by the immune system
Describe MHC class 1 proteins
Found on almost all cells
Present antigens to cytotoxic T cells
Present endogenous antigens
Describe MHC class 2 proteins
Found on antigens presenting cells - B cells and macrophages
Present to Th cells
Present exogenous antigen
List 4 conditions that are associated with inappropriate immune responses
Psoriasis
Atopic and contact dermatitis
Bullous pemphigoid
Urticaria
List some features of autoimmunity
Lymphocyte abnormality
Genetic predisposition
Hormonal influence
Anatomical alteration
Which skin conditions are autoimmune
Vitiligo - melanocytes attacked by T cells
Psoriasis
SLE - autoantibodies are formed for your own DNA