Integrity: Autoimmunity & Allergies Flashcards
Who is more susceptible to autoimmunity females or males?
Females are more susceptible to autoimmunity.
They have a better survival rate to severe infections, a better response to vaccines and less non-reproductive cancers.
However this mean immune system more susceptible to self recognising
What is it about the X chromosome that makes women have a stronger immune response
XIST (non-coding RNA) coats the Xi chromosome in the Barr body
* a danger signal (ssRNA)
* revealed to immune system after cell death by phagocytosis
What is Atopy?
A predisposition to an immune response against diverse antigens and allergens leading to CD4+ Th2 differentiation and overproduction of immunoglobulin E (IgE)
Often results in multiple sensitivities
Difference between allergy in non-atopic people and atopic people
Allergy in non-atopic people is usually isolated (bee venom, drug)
Clinical word for “hay fever”
hay fever (allergic rhinitis)
Development of IgE mediated allergic response
1st exposure to antigen in skin/mucosa
* ILC2 react; dendritic cells migrate & present antigen in node
* naïve T cells polarise to TH2 cells that induce B cells to switch to IgE production & mature
* mature IgE plasma cell
* released IgE gathered on mucosal mast cells/circulating basophils
What the 4(5) types of hypersensitivity/autoimmune responses
For each of these hypersensitivity/ autoimmune responses give an axample of a disease caused by it
- IgE - allergies
- Cell-bound IgG/IgM
- Graves’ disease: stimulates TSH receptor: hyperthyroidism
- Myasthenia gravis: blocks Ach receptor: neuromuscular
weakness
- Extracellular IgG/IgM - don’t really know
- Damage from inappropriate cytotoxic T cell killing
Autoimmunity: type 1 diabetes
* CTL kill pancreatic islet β cells (target insulin-related peptides)
Hypersensitivity: coeliac disease
* sentinel intraepithelial CD8 T cells kill intestinal epithelium stressed by cytokines from Th1 cells
sensitised to modified dietary gliadin
