Immune cell profiles Flashcards
1
Q
Macrophages
A
- One of the first cells that a pathogen is likely to encounter
- Characterised by circular nucleus with some cytoplasmic space
- Can be fixed or patrolling/wandering
- Role: Recognition of pathogen + elimination of pathogens/dead/damaged cells/ cell signalling
- Depending on where they are located, they have different names
2
Q
Dust cells
A
Alveolar macrophages located in the pulmonary alveolus of the lungs
3
Q
Histocytes
A
Specialist Macrophages located within the connective tissues
4
Q
Kupffer cells
A
Specialist Macrophages located within the liver
5
Q
Microglia
A
Specialist Macrophages found in neuronal tissue
6
Q
Epitheloid cells
A
Specialist Macrophages found in granulomas
7
Q
Osteoclasts
A
Specialist Macrophages found in the bone
8
Q
Sinusoidal lining cells
A
Specialist Macrophages found in the spleen
9
Q
Mesangial cells
A
Specialist Macrophages found in the kidney
10
Q
Neutrophils
A
- A type of granulocyte with a lifespan of 2-3 days, characterised by multi-lobed nuclei
- Has Primary + Secondary granules that act as antimicrobials
- Can also phagocytose + often attracted by chemotaxic factors
- Role: To kill
11
Q
Primary granules
A
- Contains a variety of enzymes that aid in killing pathogens ie peroxidase, lysozyme + other hydrolytic enzymes
12
Q
Secondary granules
A
- Contains chemicals or enzymes that can have regulatory functions or continue to assist in immune responses ie collagenase, lactoferrin, lysozyme
13
Q
Dendritic cells
A
- Role: Potent antigen presentation in lymph nodes, activating the adaptive immune response
- Found in most tissues
- Can be derived from circulating monocytes
14
Q
Eosinophils
A
- Motile phagocytic + granular cells that circulate in blood + can migrate into tissue spaces
- Characterised by a bi-lobed nucleus + granulated cytoplasm + stained red by eosin dye
- Role: Phagocyte that plays role in host defence against parasites as secreted contents of granules that may damage parasitic membranes
15
Q
Basophils
A
- Role: Non-phagocytic granulocyte that mediates certain allergenic sequences
- Characterised by lobed nucleus + heavily granulated cytoplasm
- Releases pharmacologically-active substances ie histamine from their granules that play a major role in certain allergenic response
16
Q
Mast cells
A
- Found in most tissues
- 2 different types:
+ Mucosal mast cells in gut
+ Connective tissue mast cells - Role: Mediator of a variety of allergic inflammatory conditions. When activated, they can increase vascular permeability, vasodilation, smooth muscle cell contraction + attract neutrophils to inflammatory site
- Activated by multiple exposures + bindings to allergen
17
Q
B cells/Plasma cells
A
- Role: When activated, they differentiate into plasma cells to produce antigen-specific antibodies
- They express:
+ Surface antibody (BCR)
+ CD19 (Co-receptor)
+ MHC-2 molecules
+ CD40 - Activated form characterised by
+ Extensive RER + Golgi apparatus
+ Plasma cells have lower levels of membrane bound Ab
18
Q
T helper cells
A
- Role: To help other immune cells become fully functional
- Characterised by CD4 expression, strict recognition + activation by antigen-class 2 MHC complex
