LBL 5 Connective Tissue and Secretions Flashcards
Name three protein fibres in the respiratory system
Collagen
Elastin
Reticulin
Name the three types of specialised cells in the respiratory system
Macrophages
Clara cells
Mast cells
Name three types of tissue found in the respiratory system
Cartilage
Smooth muscle
Lymphoid tissue
What stain is used to distinguish between elastin fibres and other connective tissue fibres?
Verhoeff-Van Gieson stain
Stained by iron-haematoxylin compound (Verhoeff)
Van Gieson is a counter-stain
Name the properties of elastin
Highly elastic protein fibre, found in the alveoli
Elastin fibres are made up of multiple sub-units of tropoelastin (will cross link with each other)
Encoded by the ELN gene
Contains fibrillin
Longest lived human proteins (half-life of 80 years)
What reticulin fibres made of?
Collagen (type III) secreted by reticular cells (type of specialised fibroblast)
Where are reticulin fibres found?
Liver
Lung
Lymph
What is used to stain Reticulin?
They are argyrophilic so they use silver stains
Examples: Gordon & Sweet’s, Jones Methenamine Silver
Properties of Mast Cells (Fat cells)
Precursor of Myeloid progenitor
Numerous in regions where it is in contact with the outside world
Travels through the blood before migrating out of the blood vessel
Contain granules of heparin and histamine
Activated by the binding of IgE
Properties of Asthma
Increases airway resistance Causes bronchial inflammation Airway hyper-responsiveness More goblet cells, smooth muscle and the basement membrane is thicker Treated with steroids
Examples of where cartilage is found
Trachea
Bronchi
Properties of Cartilage
Avascular and aneural tissue
Produced by chondrocytes
3 types: Elastic, Hyaline and Fibrocartilage
Properties of Elastic Cartilage
Principle protein type is elastin
Contains some Type II collagen
Very flexible
Found in the epiglottis
Properties of Hyaline Cartilage
Principle protein is Type II collagen
Covered in fibrous membrane
Chondrocytes exist in lacunae
Found in trachea, ribs and joints
Properties of Fibrocartilage
Contains Type I collagen
Found where 2 bones have fused together (secondary cartilaginous joints)
Can form scar tissue of collagenous structures
Attaches tendons/ligaments to bone
What is the word for Cartilage disease?
Chondropathies
Examples: Achondroplasia (inherited), Knee Injuries (trauma), Osteoarthritis (wear and tear)
Properties of mucus
Secreted by goblet cells
95% water with some smattering inorganic ions and protein
Contains mucin: helps form a gel, highly diverse (20 different mucin genes), respiratory mucus contains large amounts of Mucin 5A and 5B
What gene causes the mutation for Cystic Fibrosis?
CFTR gene (autosomal recessive)
What does cystic fibrosis cause?
Thick mucous prevents the muco-ciliary escalator from functioning.
Increases the likely hood of infections
