GV7: Chronic Inflammatory Skin Conditions Flashcards
what is chronic inflammation
manifestation of body’s response to tissue damage and infection; brings cells from blood to site of infection
what is acute inflammation
normal healing response
what is chronic inflammation
abnormal response to prolonged stimulation leading to further tissue damage and scarring
what mediates chronic inflammation
cytokines (small proteins secreted by cells of the immune system)
what is the role of the immune system
cells are activated to produce cytokines on exposure to antigen, the efficacy of the immune response affects the ability of the body to eliminate the antigen, prolonged activation of the immune system due to failure to eradicate antigen can lead to chronic inflammation
what is the function of the skin barrier
physical barrier, skin cells with fats and oil maintain structure and reduce water loss
breakdown of the barrier enables entry of irritants, allergens and pathogens
what happens after the barrier function of the skin is destroyed
allergens largely bypass innate and direct activation of B cells- IgE
bacteria activate the innate immune system then the adaptive immune system
what is eczema
inflammation (red, swelling) and intense irritation and itching
not infectious or contagious
dry skin fails to retain moisture
in eczema, reduction of fats and oils in skin leaves gaps for more water loss, cells become flaccid, more gaps for entry of bacteria and allergens
irritants contribute to the breakdown of skin
what is atopic eczema
caused by changes in the Filaggrin gene encoding a structural protein in the skin and in some people with atopic eczemal deficiency leads to skin barrier breakdown
increased levels of IgE antibodies to certain allergens
what is psoriasis
autoimmune condition resulting in increased production of skin cells
cells replaces every 3-7 days instead of 3-4 weeks
what are possible triggers of psoriasis
injury to skin, throat infections, certain medicines
how is psoriasis linked to inappropriate immune responses
LL37 peptides are produced as the body’s own antibodies to protect injured skin
LL37 is overexpressed in psoriasis and involved in activation of dendritic cells, acting as an autoantigen
triggers an immune cell response
immune cells triggered by LL37 produce key cytokines such as IL-17
what antimicrobial peptide is involved in psoriasis
LL37
what gene has mutations linked to pustular psoriasis
IL36RN
what does the gene IL36RN regulate
regulates inflammation by suppressing inflammatory cytokines such as interleukin-1 (IL-1)
