Coeliac disease - MCC Year 12 Biology

Expected learning
• To learn about auto-immune diseases and
immunodeficiency disease.
What are auto immune diseases?
• An auto-immune disease is a disease in which
the immune system fails to identify ‘self’
material and makes antibodies against the
body’s own tissues.
What are auto immune diseases?
• Sometimes the ability of the immune system
to recognize self from non-self breaks down
• When this happens, the body sometimes
thinks that some of its own cells are evading
the body and attacks them
• Some examples are: coeliac disease and MS
Coeliac disease
An auto immune disease
What is coeliac
• Coeliac sufferers are unable to break down the
gluten found in grains such as wheat.
• One of the features of coeliac disease is ‘leaky
gut syndrome’.
‘Leaky gut’ syndrome
• A small gap appears between the epithelial
cells that line the small intestine.
• Gluten fragments enter the gap and
accumulate on the tissue under the epithelial
• Macrophages are then stimulated to remove
the fragments
Like this!!!
How this is removed
• Macrophages are released when the gluten is
present in the tissue underlying the epithelial
• Macrophages swallow the gluten, enzymes
are released into the vacuole containing the
gluten and the gluten is destroyed.
Why is this an auto immune disease?
• The gluten has connected to the tissue under
the epithelial cells, so when the macrophages
attack the gluten it is also attacking the
epithelial cells.
2010 exam question
2010 exam question answers
• Question 7c.
• One of:
• cytotoxic T cell: kills infected epithelial cells
• B cells: these cells differentiate into memory and
plasma cells to produce antibodies against epithelial cells
• interleukins/cytokines: these stimulate specific
immune response against epithelial cells.
• Many answers given were unsuitable, such as NK cells,
histamines or mast cells.
Questions in the time left or
After reading ‘multiple sclerosis: an auto
immune disease’ on page 273-274…
Answer these questions:
What does MS breakdown?
What are the effects of this?
What are some of the symptoms of MS?
Can any damage be repaired? If so, under
what circumstances?
Reflection question
• What was the most interesting thing that you
learnt about either auto-immune diseases or
immunodefiency diseases?