Causes of asthma Flashcards
Bronchial Asthma is
A chronic disease involving the narrowing of airways due to inflammation
The two things influential to asthma are
Environmental and genetic factors
Asthma can be decided into two main categories with different names, name them
- Non-Allergic, intrinsic, non-atopic
2. Allergic, extrinsic, atopic
Name the major differences between natural and asthmatic airways (6)
- Mucus Plugging
- More and larger goblet cells
- Thinkend basement membrane
- More Smooth muscle tissue
- Absence of ciliated cells
- Oedema (the build up of fluid in lungs)
What are goblet cells
Mucus producing glands
What is the main function of cilia
Removal of dirty mucus out of the lungs through a beating motion
Why does a mucus plug form and what does it cause
Because the absence of ciliated cells stops the mucus produced by the many goblet cells from being removed which prevents gas exchange in the alveoli
what are mucus plugs
next to extremely disgusting they are large amounts of mucus plugging the airways, preventing whole alveoli sacks from gas exchanging
What is a Mast cell and what do they do
A granulated cell containing histamine, proteases, proteoglycans and chemotactic factors which they release upon triggering in different stages
What is eosinophil
A leukocyte involved in damaging epithelial cells and growth factor release leading to hyperplasia
How are eosinophil’s and mast cells primed for function?
- Allergen detected by t cell
2.T cell activated and released interleukin 4, 5 and 9 - interleukin 4 activated B type leukocytes that differentiate into plasma cells that then produce IgE antibodies
- interleukin 5 and 9 activate eosinophil and allow IgE to bind to it.
- IgE also binds to mast cells
the binding of antibodies to these two cells primes them and can now be triggered
What triggers mast cells
The detection of an allergen by IgE primed mast cells causes them to do their thang, including attracting more e eosinophils through chemotactic response
What triggers eosinophil
the detection of an allergen by IgE primed eosinophil causes them to release their thangs
The early mediators/enhancers of asthma are
Histamine - causing contracting of smooth muscle (by mast cell)
Chemotactic factors - attract leukocytes like eosinophils and neutrophils into lung tissue
Later Mediators/enhancers of asthma are
Leukotrienes d4, c4, e4 and Prostaglandin d2 all have the same effects as histamine but then in the later stages (still mast cell)
epithelial desquamation, cell death are caused by proteins released from the earlier attracted eosinophils
