Lymphatics and Immune Systems DYK Questions Flashcards
Can you describe the order of fluid circulation (including spaces and vessels)?
Peripheral tissues —> lymphatic capillaries —> lymphatic vessels —> subclavian veins
Do you know the differences in structure and function between lymphatic and blood vessels?
LYMPHATICS origin - as 'pockets' size - larger wall thickness - thinner BLOOD VESSELS origin - continuous tubes size - smaller wall thickness - thicker
Can you name the physical barriers we have?
Skin, mucous membranes
Can you name the most common phagocytes?
Neutrophils
Monocytes
How do phagocytes remove debris and foreign material?
□ Non-specific immune cells
□ Serve as ‘police’
□ Remove cellular debris and foreign material
○ Engulf debris - ‘eating’ debris in a PacMan style
Includes pathogens
Which cells carry out immune surveillance?
Natural killer (NK) cells
When do interferons most commonly get released?
Released by activated lymphocytes, macrophages, virus-infected cells
What cells and immune components does complement work closely with to improve the effectiveness of the immune response?
phagocytes and antibodies
What are the 4 characteristics of tissues undergoing inflammation?
Inflammatory mediators
Blood flow
Phagocytes
Capillary permeability
(redness, swelling, heat, pain)What is the aim of inflammation?
- All parts of inflammation increase immune function
○ Prevent infection in wound sites
Increases effectiveness of other defences (both specific and non-specific)
Name 2 things that increasing the body temperature does to assist with protecting the body?
○ Inhibits pathogens - not comfortable for them
○ Raises metabolic rate
○ Faster mobilisation of tissue defences
Accelerated repair process
Can you briefly describe the difference between an antigen and an antibody?
Antigen: molecule capable of inducing an immune response (production of an antibody) in the host organism, generates a response
Antibody: immunoglobulin, Y shaped proteins that are produced by the immune system, stops intruders from entering the body
Can you name the process that occurs that links the non-specific (innate) immune response to the specific (adaptive) immune response?
ANTIGEN PRESENTATION
What are the cells called that carry out antigen presentation process?
phagocytes
T and B cells (lymphocytes)
Can you name the types of lymphocytes that provide us with specific (adaptive) immunity?
T cells and B cells
Is specific (adaptive) immunity present at birth?
no
Can you name the 4 key characteristics of specific immunity that make it different to non-specific immunity?
Specific - Activated by specific antigens
Versatile - Diversity of lymphocytes present, can be ready for any antigen at any time
Memory - Antigens previously encountered are remembered (principle behind vaccination)
Tolerance - All cells in the body have antigens, no immune response against those
Can you name the cell that carries out cell mediated immunity?
T cells
How do cytotoxic T cells remove cells with foreign or abnormal antigens?
Seek out and destroy abnormal cells, Release perforin (perforate cell membrane), Secrete lymphotoxin to kill the cell, Activate genes in nucleus which Tells cell it needs to die
Why are memory cells important in protecting against future infection?
Recognise same antigen if re-exposed
What is the key role of T helper cells?
Coordinate specific and non-specific defences,
Secrete cytokines
○ Stimulate T cell division (produce memory helper T cells, speed maturation of cytotoxic T cells)
○ Attract macrophages to affected areas - stimulate phagocytic activity
○ Attract cytotoxic T cells - another means of destroying abnormal cells/pathogens
○ Activate B cells - antibody production
Why do you think it is important for suppressor T cells to regulate immune responses?
- Supress response of other T cells.
- Once infection is cleared, process needs to stop
- Like negative feedback of the immune response
What is produced by plasma cells (differentiated B cells) as part of the specific immune response?
secrete antibodies (proteins)
What key feature do plasma cells (differentiated B cells) have that make it effective?
Antibody has receptors specific for the antigen its just been exposed to
Can you name the cell that is activated when you are exposed to an antigen a second (third, fourth, etc) time?
Memory B cells mainly
IgG
IgM
Why do you think the secondary response is much faster than the primary response?
There is more IgG now, it already knows how to fight it. Production of IgM is quicker. Both IgG and IgM stay for extended periods of time
