Lecture 3 Flashcards
An antigen is?
a part of an organism or substance that is recognized by the immune system as non-self
-often cell-surface protein or sugar
Passive immunity
- preformed antibody acquired from an outside source
- half-life of ~21 days
Non-specific Immunity (Anatomical Defences)
- Skin/Hoof/Hair, mucous membranes
- mucus
- Cilia
- Lacrimal secretions
Non-specific immunity(Humoral defences)
- play a role in inflammation
- complement system
- cytokines
- lysozyme
Lysozymes function? found in?
Found in tears
-breaks down the cell wall of bacteria
Cytokines are?
communication molecules
The three roles of the complement system include?
complement fixation
opsonisation
trigger inflammatory reaction
Complement fixation
binding to and destroying foreign cell membranes
Opsonisation
tagging of foreign cells for stimulation of phagocytosis
Non-specific Immunity(cellular defences)
phagocytes
- lack memory
- contribute to inflammatory response
Neutrophils
- WBC
- PMNSs
- ingest and digest foreign particles by lysozyme digestion
- very non-specific
Neutrophils attracted to sites of infection and inflammation by?
chemotaxis
-chemical signaling from cytokines and interleukins
Neutrophil activation
become sticky, marginate in circulation, squeeze through endothelial junctions(diapedesis) and migrate to the site of infection or tissue damage
Neutrophils are specifically important in?
mammary glands and uterus
Monocytes
largest WBC
5-8%
cytoplasm contains lysosomes
eventually leave circulation to become macrophages in tissue